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HHII NNGGHH KKHHOOAA HHCC BB MMNN BBOO CCHH

BBOO CCOO KKHHOOAA HHCC

H NI, THNG 4/2011

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NGHIN CU MT S YU T NH HNG N KH NNG GII PHNG PIROXICAM T HN DCH NANO .............................................................. 1 Nguyn Th Mai Anh

NGHIN CU NH HNG CA MT S YU T N S GII PHNG DC CHT T VIN PSEUDOEPHEDRIN 60 mg .................................................. 9 inh Th Hi Bnh, L Th Ngc Dip

NGHIN CU NH HNG CA HYDROXYPROPYL--CYCLODEXTRIN N N NH CA PANTOPRAZOL ................................................................ 16 Phm Xun Chung

NGHIN CU NH LNG ITRACONAZOL TRONG CH PHM VIN NANG BNG PHNG PHP VI SINH .................................................................... 25 Trn Trnh Cng

VI CU KIM SOT GII PHNG - KT DNH NIM MC V NG DNG TRONG CI THIN HP THU ACICLOVIR QUA NG TIU HA ................................................................................................................................ 31 V Th Thu Giang, Phm Th Minh Hu, Nguyn Thu Hin

NGHIN CU BO CH NANO NH TNG NH MT DICLOFENAC V NH GI KH NNG GII PHNG DC CHT IN VITRO CA CH PHM .................................................................................................................... 40 ng Th Hin, V Ngc Mai, Nguyn Trn Linh

NGHIN CU BO CH VIN NN CAPTOPRIL GII PHNG KO DI BNG PHNG PHP DP NHIU LP ................................................................. 49 Hong Ngc H, Phm Th Minh Hu

M HNH TH GII PHNG IN VITRO CA DNG THUC TI CH GII PHNG TI I TRNG ................................................................................... 59 Nguyn Thu Qunh

PREPARATION AND INVESTIGATION OF SELECTIVE ACCUMULATION AND PDT EFFECTIVENESS OF LIPOSOMES LOADED WITH PHOTODITAZIN ........................................................................................................... 69 Trn Th Hi Yn

CH MC TC GI ...................................................................................................... 73

HI NGH KHOA HC B MN BO CH - 04/2011

NGHIN CU MT S YU T NH HNG N KH NNG GII PHNG PIROXICAM T HN DCH NANO

Nguyn Th Mai Anh

1. t vn

Trong nhng nm gn y, bo ch thuc da trn cng ngh nano ang l mt trong nhng bin php y trin vng c quan tm nghin cu v ng dng trong ngnh dc. Cng ngh ny c xem nh em li cuc cch mng trong lnh vc pht trin thuc do to ra c nhng ch phm mi, h dn thuc mi t hiu qu iu tr vt tri trn nhng dc cht sn c. Nhng thnh cng ni bt t cc thuc nano c c l do nhng c im mi ring bit ca ca tiu phn nano lin quan n gii phng v hp thu dc cht. Tuy nhin, c ch gii phng dc cht t h nano rt phc tp v qu trnh gii phng ph thuc vo nhiu yu t: t nguyn liu, t dc n k thut bo ch. Do chng ti thc hin ti: Nghin cu mt s yu t nh hng n kh nng gii phng piroxicam t hn dch nano".

2. i tng, nguyn liu, phng php nghin cu

2.1. i tng nghin cu: piroxicam

2.2. Nguyn liu: piroxicam (Px- Trung Quc), tiu chun USP 30, Eudragid RS 100 v alcol polyvinic (PVA- c). Mt s dung mi, ha cht tinh khit ha hc dng cho bo ch v phn tch.

2.3. Thit b: My khuy Braul 4185 (Sc), my ly tm Sigma 3-18 K Satorius (c), knh hin vi in t qut FESEM Hitachi S-4800 (Nht), knh hin vi in t truyn qua JEM 1010 (JOEL), my xc nh phn b kch thc ht HORIBA LA-950, my HPLC Spectra System Thermo, my o th Zeta Phoremeter IV-CAD, RKIN ELME, h thng nh gi gii phng thuc qua mng Hanson Research, mng polysulfon 0,45 m, mng cellulose acetat Sartorius 0,45 m. Mt s thit b bo ch, kim nghim khc.

2.4. Phng php nghin cu

2.4.1. Ch to v nh gi mt s c tnh ca h nano piroxicam

Ch to h nano piroxicam bng phng php nh ha v bc hi dung mi sau nh gi hnh dng, kch thc, cu trc tnh cht in b mt tiu phn nano, xc nh hm lng dc cht trong h nano [1]

ng kh hn dch nano vi cc thng s: ng lnh - 70OC trong 8 gi, lm kh s cp - 15OC, tc gia nhit 0,50C/ 1 pht, thi gian lu 20 gi, lm kh thc cp 30OC, tc gia nhit 0,250C/ 1 pht, thi gian lu 8 gi.

2.4.2. Bo ch hn dch nano piroxicam

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Hn dch nano c bo ch bng phng php phn tn. Kho st nh hng ca cc thnh phn trong mi trng phn tn n n nh cu trc ha l ca hn dch da vo tc sa lng v hin tng kt t tiu phn.

2.4.3. nh gi kh nng gii phng dc cht

Cc iu kin c th nh sau:

Mng cellulose acetat, kch thc l xp 0,45 m. Mi trng khuch tn: dung dch nc mt nhn to (natri clorid 6,70g; calci clorid 0,08g; natri bicarbonat 2,00g; nc ct va 1000ml [7]). Th tch mi trng khuch tn: 7ml. Nhit mi trng: 340C 1. Din tch b mt khuch tn: 0,8 cm2. Tc khuy: 400 vng/pht. Lng mu em th: 0,3 ml (tng ng 1,5 mg dc cht). Ly mu sau mi gi, xc nh lng piroxicam gii phng bng phng php HPLC [1].

3. Kt qu v bn lun.

3.1. ng kh h nano hn dch

Nhiu bo co khoa hc cho rng ng kh l gii php ti u loi ht dung mi v trnh c hin tng kt t tiu phn, n nh cu trc ht [2], [4]. Trong phm vi nghin cu ny, cc t dc to khung c s dng l glucose, sorbitol, manitol v PVA. Mu sau khi ng kh c cu trc bnh nguyn vn, th cht xp, xp v kiu xp khc nhau cha cc tiu phn hnh cu u n, b mt nhn v a s ht c kch thc nh hn 1000 nm, cu trc ht gm hai phn: v ngoi l polyme, nhn bn trong l dc cht (Hnh 1).

(a) (b)

Hnh 1: Hnh dng, cu trc cc tiu phn trong h nano

(a) nh chp t knh hin vi in t qut, (b) nh chp t knh hin vi in t truyn qua

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Phn tch hnh nh chp qua knh hin vi in t qut (Hnh 2) c th nhn thy: cc tiu phn dc cht c phn tn u trn t dc to khung, khng kt dnh nhau, phn tn d dng trong nc , c bit l cc mu ng kh vi manitol v PVA. V vy PVA v manitol c la chn cho nhng th nghim tip theo.

(a) (b)

Hnh 2: Hnh nh cc tiu phn trong h nano sau khi ng kh

(a): PE ng kh vi manitol; (b): PE ng kh vi PVA

3.2. Bo ch hn dch nano

H nano sau khi ch to c kim tra hm lng dc cht bng phng php sc k lng hiu nng cao. Hm lng Px trong h khong 12%, . Cc mu ny c bo qun nhit phng (25-35OC, m 40-70%). Sau 3 thng, sn phm khng c s thay i v hnh dng, mu sc ca bnh ng kh, hm lng dc cht khng thay i, d phn tn li trong nc v soi di knh hin vi khng thy c hin tng kt t tiu phn. H ny c s dng lm nguyn liu bo ch hn dch.

Vi mc tiu ban u l hn ch n mc ti a hin tng kt t tiu phn trong mi trng lng, hn dch c nghin cu xy dng cng thc nh sau:

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Nano piroxicam tng ng vi 0,5g piroxicam Acid citric monohydrat 0,2 g Natri hydroxyd 0,1 g Benzalkonium clorid 0,02 g Manitol 4,00 g Nc pha tim v 100 ml

Hnh 3: Tiu phn nano phn tn trong

mi trng lng

3.3. Kho st nh hng ca mt s thnh phn trong cng thc n kh nng gii phng dc cht t hn dch

3.3.1. nh hng ca nguyn liu bo ch hn dch n kh nng gii phng dc cht

Bo ch hn dch t 2 nguyn liu l h nano ng kh cha manitol v h nano ng kh cha PVA, nh gi kh nng gii phng dc cht t hn dch theo phng php trnh by mc 2.4.3. Kt qu th hin trn th gii phng thuc t hn dch qua mng cellulose acetat trong hnh 4 cho thy hn dch bo ch t h nano cha PVA gii phng dc cht rt t.

Hnh 4: th gii phng piroxicam t hn dch bo ch da trn 2 h nano vi t dc ng kh l manitol v PVA.

Mt khc, khi quan st nguyn liu sau 6 thng, bt ng kh cha manitol khng thay i th cht v cu trc, trong khi bt ng kh cha PVA gim xp, phn tn trong nc kh khn hn, phn tch hnh nh chp qua knh hin vi in t qut nhn thy cu trc khi bt thay i ng k (Hnh 5). Nh vy, c th ni PVA b bin

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i trong qu trnh bo qun hoc c tng tc vi lp v Eudragit bao quanh tiu phn nano nn lm cn tr gii phng dc cht. Do , h nano ng kh s dng t dc to khung manitol c s dng bo ch hn dch trong nhng th nghim tip theo.

(a)

(b)

Hnh 5: H nano ng kh cha PVA

(a): ngay sau khi bo ch (b): sau 6 thng bo qun nhit phng

3.3.2. nh hng ca cht din hot n kh nng gii phng dc cht

Vi mc ch lm tng kh nng thm ca dc cht qua mng, hn dch nano c bo ch vi mt s t l benzalkonium clorid (Ben.) khc nhau kt hp vi s dng Tween 80. Kt qu th gii phng cho thy, ti nhng nng Ben. kho st (0,02%; 0,04%; 0,06%), lng Px gii phng t cc hn dch nano qua mng cellulose acetat thay i khng ng k. Khi kt hp 0,02% Ben. vi 0,2% Tween 80, kh nng gii phng ca dc cht tng ln mt cht (kt qu th hin th trn hnh 6).

3.3.3. nh hng ca cht lm tng nht n kh nng gii phng dc cht

nht ca mi trng phn tn l mt trong nhng yu t quan trng quyt nh n nh cu trc l ha ca hn dch v sinh kh dng ca thuc nh mt. Trong ni dung ca nghin cu ny, hn dch c bo ch vi mt s t l HPMC khc nhau (0%; 0,1%; 0,3%; 0,5% v 1 %). Thc t th gii phng thuc t hn dch (hnh 6) cho thy: trong nhng mu kho st, Px c gii phng t hn dch cha 0,1 % HPMC l cao nht, cc hn dch cn li, kt qu thc nghim khc nhau khng ng k, do nng HPMC 0,1% c la chn bo ch hn dch.

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Hnh 6: th gii phng piroxicam t cc hn dch nano c nng cht din hot khc nhau

Hnh 6: th gii phng piroxicam t cc hn dch nano cha nng HPMC khc nhau

3.4. nh gi kh nng gii phng dc cht qua mng sinh hc

Gic mc mt th c bc tch cn thn trong vng 1gi ngay sau khi th cht, ra sch, ngm trong nc mui sinh l v dng th gii phng thuc trong vng 6 h m bo nim mc cn trong sut v nguyn vn. Xc inh lng Px thm qua mng bng phng php sc k lng hiu nng cao.

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Hnh 7: th gii phng piroxicam qua gic mc mt th bc tch

Vi kt qu th hin hnh 7, lng Px trong hn dch cha Tween 80 thm qua gic mc cao gp 3 ln so vi hn dch khng cha Tween 80. C th kt lun rng: cht din hot th hin r vai tr lm tng tnh thm ca dc cht qua mng sinh hc do lm thay i tnh cht ca mng.

4. Kt lun

Vi cc kt qu kho st trn, chng ti la chn c cng thc hn dch nano gii phng dc cht tng i tt vi nhng thnh phn nh sau:

Nano piroxicam tng ng vi 0,5 g piroxicam

Acid citric monohydrat 0,2 g

Natri hydroxyd 0,1 g

Benzalkonium clorid 0,02 g

Tween 80 0,2 g

Manitol 4,00 g

Nc pha tim v 100 ml

Ti liu tham kho

1. Nguyn Th Mai Anh v cng s, Nghin cu bo ch v nh gi mt s c tnh ca h nano piroxicam, Tp ch dc hc (2009), s 8/2009, trang 50-53.

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2. Wassim Abdelwahed, Freeze-drying of nanoparticles: Formulation, process and storage considerations, Adv. Drug Del. Rev. (2006), 58, p. 16881713.

3. Khosro Adibkia et al, "Piroxicam nanoparticles for ocular delivery: Physicochemical characterization and implementation in endotoxin-induced uveitis", J. Drug Target. (2007), 15, 6, p.407-416,

4. Min Kyung Lee, Cryoprotectants for freeze drying of drug nano-suspensions: Effect of freezing rate, J. Pharm. Sci., Inpress (2009), p.1-10.

5. Vikas Mittal, Advanced polymer nanoparticles (2011), CRC Press. 6. Ram N. Prajapati et al, "Dendimer-mediated solubilization, formulation

development and in vitro, in vivo assessment of piroxicam", Mol. Pharm. (2009), 6, 3, p. 940 950.

7. Sultana Yasmin et al (2006), Ion-Activated, Gelrite - Based in Situ Ophthlamic Gels of Pefloxacin Mesylate: Comparison with Conventional Eye Drops, Drug Delivery, 13, p 215 219.

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NGHIN CU NH HNG CA MT S YU T N S GII PHNG DC CHT T VIN PSEUDOEPHEDRIN 60 mg

inh Th Hi Bnh, L Th Ngc Dip

t vn

Pseudoephedrin c tc dng co mch lm gim sung huyt, thng c kt hp vi mt s hot cht khc tng hiu qu iu tr bnh vim mi d ng Pseudoephedrin thng dng di dng mui sulfat hoc hydroclrid, d tan trong nc, c thi gian bn thi ngn (khong 5-8 gi), nu bo ch di dng tc dng ko di s nng cao c hiu lc iu tr, gim tc dng khng mong mun. gp phn to ra dng thuc mi cho pseudoephedrin, chng ti tin hnh nghin cu kho st nh hng ca mt s yu t n s gii phng dc cht t vin pseudoephedrin 60mg gii phng dc cht c kim sot bo ch di dng ct ha tan.

Nguyn liu, thit b v phng php nghin cu

Nguyn liu: pseudoephedrin sulfat, hydroxypropyl methyl cellulose 100K (HPMC 100K), lactose, magnesi stearat, talc t tiu chun dc dng; cc ha cht khc t tiu chun tinh khit phn tch.

Thit b nghin cu: my dp vin o lc nn Pye Unicam, my dp vin tm sai KP - 2, my th ha tan ERWKA DT 60 (c), my o cng ca vin nn ERWEKA TBH20 (c), my o quang UNICAM UV3000, my o trn chy ERWEKA GWF (c), my o t trng biu kin ERWEKA SVW, my o mi mn ERWEKA TA10 v cc thit b bo ch, phn tch khc.

Phng php nghin cu

Phng php bo ch vin

Dc cht v t dc c trn u. Ry qua ry 250 nm. Hn hp bt em dp trn my dp vin Pye Unicam vi chy c ng knh 8 mm. Khi kho st qui m ln hn, vin c dp bng my dp vin tm sai KP 2. nh gi hn hp bt trc khi dp vin: m, trn chy, khi lng ring biu kin ca bt, ch s nn ca bt. nh gi mt s ch tiu vin nn: cng, mi mn, ng u khi lng vin.

Th nghim ha tan

S dng my th ha tan ERWEKA DT60 vi cc thng s sau:

- My cnh khuy, tc khuy 50 vng/ pht

- Mi trng ha tan: 900ml m pH 6,8

- Nhit mi trng: 370C 0,5

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- Thi gian th 12 gi, ly mu nh lng sau 1 gi, 2 gi, 4 gi, 6 gi, 8 gi, 12 gi. Xc nh lng pseudoephedrin ha tan theo phng php o quang ti bc sng 266 nm

Thit k th nghim

B tr th nghim theo phng php hp t ti tm vi s tr gip ca phn mm MODDE 5.0.

Kt qu nghin cu v bn lun

M hnh bo ch vin pseudoephedrin gii phng dc cht c kim sot c la chn trong nghin cu l dng ct ha tan. Da vo cc ti liu tham kho, nh gi nh hng ca mt s yu t ti s gii phng dc cht t vin chng ti la chn cng thc c bn cho vin pseudoephedrin nh sau:

Pseudoephedrin sulfat 60mg

HPMC 100K (mg) thay i

Lactose (mg) thay i

Magnesi stearat 3 mg

Talc 7 mg

Lc dp vin thay i

Trong : HPMC 100K l t dc to ct, kim sot gii phng pseudoephedrin theo c ch trng n to thnh hng ro gel lm chm tc gii phng dc cht. Lactose l t dc n gip cho qu trnh dp vin c d dng hn, vin m bo bn c hc, tan trong nc to knh khuch tn tng gii phng dc cht. Magnesi stearat, talc: t dc trn ci thin trn chy ca khi bt, chng dnh chy ci, lm b mt vin bng p.

Kho st mt s tnh cht hn hp bt trc khi dp vin

m: 2,54 0,20 %. trn chy: 43 0,48 (g/s). Bt trn chy tt. Khi lng biu kin: 0,49 0,04 (g/ml). Ch s nn: ch s nn trung bnh ca bt l 15,9 1,4%. Kho st mt s tnh cht ca vin

Cm quan: vin hnh tr dt, mu trng, cng chc, b mt bng p, cnh v thnh vin lnh ln.

mi mn: mi mn trung bnh t 0,67 0,02%. cng: cng trung bnh khong 8,4 0,2 kP. ng u khi lng: 365 9,15 mg, tt c cc mu u nm trong khong

cho php ( 7,5%).

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Hm lng dc cht trong vin: hm lng trung bnh l 95,13 0,26% so vi hm lng l thuyt.

Phng php bo ch dp thng c th p dng c do khi trn dc cht vi cc t dc, bt to ra c trn chy v kh nng chu nn tt. Vin bo ch c c im chc bn, bng p, khng b bong mt, st cnh. Do HPMC 100K rt d ht m cho nn qu trnh bo ch phi c thc hin trong mi trng c m thp. S khc nhau v kch thc tiu phn v iu kin bo ch m thp dn ti vic tng lc ht tnh in gia cc tiu phn, do kh trn ng nht. khc phc nhc im ny, trong qu trnh bo ch phi ch nhiu ti cng on nghin v trn bt v nu khng phn b ng u dc cht v t dc c bit l HPMC 100K th s nh hng rt ln n s ng u gii phng dc cht gia cc mu vin, cc l m. Ngoi ra trong qu trnh dp vin, m bo s ng nht gia cc mu vin cn ch n thi gian nn. Trong nghin cu ny, thi gian cho tt cc mu vin l 10 giy.

Thit k th nghim v kt qu thc nghim Qua tham kho ti liu v nghin cu sng lc nhn thy cc t dc HPMC

100K, lactose v lc dp vin l nhng yu t nh hng nhiu n s gii phng dc cht ca vin, c la chn lm bin u vo. K hiu v cc mc ca bin c lp trnh by bng 1.

Bng 1: K hiu v cc mc ca bin c lp Bin c lp K hiu Cc mc m ha

- -1 0 1 HPMC 100K (mg) X1 35 70 105 140 175 Lactose (mg) X2 0 35 70 105 140 Lc dp vin (kg) X3 500 1000 1500 2000 2500

La chn bin ph thuc l % gii phng dc cht khi vin ti cc thi im ly mu, k hiu l Yi (vi i = 1 gi, 2 gi, 4 gi, 6 gi, 8 gi, 10 gi, 12 gi).

Thit k th nghim bng phng php thit k hp tm nh phn mm MODDE 5.0 thu c 16 th nghim nh sau:

Bng 2: Bng thit k th nghim

Cng thc X1 X2 X3 Cng thc X1 X2 X3 CT1 -1 -1 -1 CT9 -2 0 0 CT2 1 -1 -1 CT10 2 0 0 CT3 -1 1 -1 CT11 0 -2 0 CT4 1 1 -1 CT12 0 2 0 CT5 -1 -1 1 CT13 0 0 -2

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Cng thc X1 X2 X3 Cng thc X1 X2 X3 CT6 1 -1 1 CT14 0 0 2 CT7 -1 1 1 CT15 0 0 0 CT8 1 1 1 CT16 0 0 0

Tin hnh bo ch 16 cng thc (mi m 100 vin) v th ha tan theo phng php bo ch trnh by, kt qu thu c trong bng 3.

Bng 3: % dc cht gii phng t vin pseudoephedrin sulfat 60 mg ca cc cng thc thc nghim

TN % DC gii phng ti i gi Y1 Y2 Y4 Y6 Y8 Y10 Y12

CT1 27,06 37,17 53,73 65,6 76,64 87,29 93,59 CT2 18,02 23,94 34,09 42,61 49,49 55,01 60,66 CT3 63,26 81,27 95,27 97,98 99,95 99,96 99,97 CT4 20,94 29,24 41,45 50,99 59,48 65,86 70,89 C5 25,15 35,57 48,44 59,38 68,94 75,72 82,79 CT6 15,86 21,19 29,45 37,68 42,86 47,88 52,96 CT7 66,12 85,47 96,63 98,2 99,52 99,95 99,98 CT8 19,25 25,86 38,95 47,79 55,67 61,92 67,77 CT9 80,37 86,56 99,44 99,33 99,39 99,65 100,04 CT10 16,34 23,41 34,7 42,83 49,52 56,22 62,9 CT11 19,22 28,25 41,23 51,28 60,63 68,66 76,21 CT12 68,79 76,56 86,27 93,47 99,4 99,31 99,27 CT13 32,01 41,04 54,88 63,78 71,6 79,11 86,73 CT14 18,13 26,5 39,27 50,13 58,83 65,24 72,17 CT15 15,2 23,34 35,54 45,72 53,55 61,32 68,5 CT16 15,74 22,7 35,21 46,23 53,69 60,79 68,07

nh hng ca cc bin c lp n s gii phng dc cht t vin

X l s liu bng phn mm INFORM 3.1. T nh gi nh hng ca cc yu t: HPMC 100K, lactose, lc dp n qu trnh gii phng dc cht t vin pseudoephedrin sulfat 60 mg gii phng c kim sot thng qua gi tr R2 ca qu trnh luyn mng v phn tch mt p. Cc thng s ca qu trnh luyn mng c th hin bng 4.

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Bng 4: Cc thng s ca qu trnh luyn mng

Bin ph thuc S ln luyn R2 luyn Y1 1000 99,6226

Y2 1000 97,845

Y4 1000 97,6655

Y6 1000 99,1094

Y8 1000 97,3281

Y10 1000 95,9082

Y12 1000 96,5942

Nh vy R2 luyn > 95% chng t bin c lp v bin ph thuc c quan h cht ch vi nhau.

nh hng ca cc bin c lp n gii phng dc cht ti cc thi im c th hin thng qua mt s mt p cc hnh sau:

Hnh 1. nh hng ca HPMC 100K v lc dp vin (khi lng lactose: 70 mg) n s gii phng pseudoephedrin sulfat ti thi im sau 1 gi

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Hnh 2. nh hng ca HPMC 100K v lactose (lc dp vin: 1500 kg) n s gii phng ca pseudoephedrin sulfat ti thi im sau 4 gi

Hnh 3. nh hng ca HPMC 100K v lactose (lc dp vin: 1500 kg) n s gii phng ca pseudoephedrin sulfat ti thi im sau 8 gi

nh hng ca HPMC 100K nh hng ca lng HPMC 100K n % dc cht gii phng th hin cc

mt p (hnh 1., hnh 2. v hnh 3.): lng HPMC 100K tng, t l gii phng dc cht gim tt c cc thi im. Tuy nhin khi lng HPMC tng t 147 mg n 175 mg, tc gii phng ca pseudoephedrin sulfat gim chm. iu ny c th gii thch l do khi lng HPMC 100K t n mt mc nht nh, lp gel hnh thnh rt vng chc, vic tng t l HPMC 100K ch lm gim nh s gii phng dc cht. Mt khc, khi HPMC 100K gim n khong 60 mg th gim lng HPMC 100K tc gii phng ca pseudoephedrin sulfat gim khng ng k c bit khi thi gian gii phng dc cht tng. Nguyn nhn c th do HPMC 100K l t dc thn nc c bn cht polyme, khi lng HPMC 100K tng, lp gel to thnh do trng n s dy hn, lm dc cht khuch tn ra ngoi mi trng gim i. Khi lng HPMC 100K thp th lp gel to thnh t, tc dng kim sot gii phng mt dn.

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nh hng ca lactose Thay i lng lactose nh hng n tc gii phng dc cht do lactose tan

trong nc to knh khuch tn. Khi lng lactose thp (t 84 mg tr xung), lactose hu nh khng nh hng ti tc gii phng dc cht. Trong cng thc lactose ng vai tr l t dc n, gip cho qu trnh dp vin c d dng hn, vin m bo bn c hc ng thi lm tng kh nng gii phng dc cht ca vin.

nh hng ca lc dp vin Lc dp vin c nh hng n s gii phng dc cht t vin. khong 1300

kg n 2500 kg th lc dp vin hu nh khng nh hng n tc gii phng dc cht khi vin. Nhng lc dp vin khong t 1300 kg n 500 kg, tc gii phng dc cht tng khong t 16,62% ln 19,62% ( thi im sau 2 gi) c th do lc dp vin thp vin tr nn xp hn, do vy lm tng tc r ca vin dn ti tng tc gii phng hot cht.

Kt lun

Cc yu t nghin cu: HPMC 100K, lactose v lc dp vin c nh hng nht nh n s gii phng dc cht t vin pseudoephedrin 60mg. Nguyn liu to ct HPMC 100K c vai tr chnh trong vic ko di gii phng dc cht c v thay i lng ca t dc ny c th kim sot c s gii phng dc cht t vin pseudoephedrin 60 mg.

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NGHIN CU NH HNG CA HYDROXYPROPYL--CYCLODEXTRIN N N NH CA PANTOPRAZOL

Phm Xun Chung

1. t vn

Pantoprazol (PTZ) l mt cht thuc nhm benzimidazol. Cng ging nh cc cht khc cng nhm, PTZ khng bn, d b phn hy trong mi trng acid [1],[9] nn c nhiu bin php c p dng lm tng n nh ca chng nh: s dng t dc kim [10] hoc hn hp t dc kim [4], s dng cc cht chng oxy ha, bo ch dng vin bao tan trong rut [6],[7],[8],[9] hoc dng ch phm ng kh Mc tiu ca nghin cu ny l nh gi nh hng ca hydroxypropyl--cyclodextrin n n nh ca ch phm ng kh PTZ.

2. Nguyn liu, thit b v phng php nghin cu

2.1. Nguyn liu

- Natri pantoprazol sesquihydrat, xut x: Ty Ban Nha, t tiu chun Dc in Chu u (EP6).

- Cc t dc: natri hydroxyd, manitol, arginin, dinatri EDTA (Trung Quc), hydroxypropyl--cyclodextrin (Trung Quc) t tiu chun nh sn xut.

- Cc ha cht tinh khit phn tch: acetonitril, natri dihydrophosphat, dinatri hydrophosphat, dikali hydrophosphat v acid phosphoric (Merck), t tiu chun nh sn xut.

- Nt nhm (Vit Nam), nt cao su (c), l thy tinh trung tnh (c), t tiu chun nh sn xut. 2.2. Thit b

- My ng kh LABCONCO. - My lc mng SATORIUS vi mng lc c kch thc 0,2 m. - My o pH Inonab pH 370. - My sc k lng hiu nng cao hiu SHIMADZU 10AVP. - T sy, t vi kh hu CLIMACELL. - My phn tch nhit vi sai SETARAM DSC131.

2.3. Phng php nghin cu 2.3.1. Phng php phn tch nhit vi sai (DSC)

Nghin cu tnh cht nhit hc v tng tc ha l ca PTZ vi t dc, t la chn c cc t dc lm tng tnh n nh ca hot cht trong cng thc ch phm ng kh PTZ bng phng php phn tch nhit vi sai (DSC). Vi cc iu kin:

- Tc qut: 10OC/pht.

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- Khong qut: 25 - 250OC. - Mu chun: nhm hydroxyd. - Mi trng: khng kh.

2.3.2. Phng php ng kh Bo ch ch phm ng kh PTZ 40 mg bng phng php ng kh vi cc

thng s: - ng lnh: -70OC, thi gian: 6 gi. - Sy s cp: -15OC, thi gian: 20 gi, tc gia nhit: 0,5OC/1 pht. - Sy th cp: +25OC, thi gian: 20 gi, tc gia nhit: 0,25OC/1 pht.

2.3.3. Phng php sc k lng hiu nng cao (HPLC) Xc nh hm lng PTZ v t l tp cht trong ch phm ch phm ng kh

bng phng php HPLC. Vi cc iu kin: - Pha ng : Acetonitril v m phosphat pH7. - Ct HPLC: C18 (5 m) 4,6 x 150mm. - Detector t ngoi: bc sng 290nm. - Th tch tim: 20 l. - Tc dng: 1ml/pht.

2.3.4. Phng php lo ha cp tc nh gi mt s ch tiu cht lng ca ch phm ng kh nh: hnh thc ca

bt ng kh; mu sc, trong ca dung dch pha li; hm lng PTZ, t l tp cht.Vi cc iu kin:

- Cng bc: trong t 100OC. - Trong t vi kh hu: nhit 40OC 2, m 755%. - iu kin phng th nghim: nhit 25OC 35OC, m 55% - 85%.

3. Kt qu nghin cu v bn lun 3.1. Kt qu nghin cu nh hng ca hydroxypropyl--cyclodextrin n n nh ca PTZ

nh gi nh hng ca hydroxypropyl--cyclodextrin (HP--Cyd) n n nh ca PTZ trong cc hn hp vt l M1, M2, M3 gm: PTZ, manitol v HP--Cyd bng phng php DSC vi cc iu kin c ghi phn 2.3.1. Kt qu c trnh by trong bng 1 v hnh 1:

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Kt qu hnh 1 cho thy: ng nhit ca cc hn hp vt l M2, M3 gm PTZ, manitol, HP--Cyd c pic rng trong khong 50-100OC (tng ng vi s mt nc ca HP--Cyd), mt pic thu nhit mnh khong 160-170OC (tng ng im chy ca manitol), mt pic ta nhit khng c trng khong 190OC (tng ng nhit phn hy ca PTZ) c cng tng ng (8mW v 21,4mW) thp hn so vi pic ta nhit ca PTZ trong hn hp M1 (53mW) v PTZ t do (130mW). iu ny c th c gii thch nh sau: HP--Cyd l t dc c kh nng n nh cc hot cht khng bn, do to ra cc khung bao bc xung quanh phn t hot cht cho nn

hn ch s tip xc ca hot cht vi mi trng xung quanh, tuy nhin y ch l hn hp vt l nn vn cn cc phn t PTZ t do, trong qu trnh gia nhit ch nhng phn t PTZ tip xc vi HP--Cyd mi to phc hn hp PTZ - HP--Cyd, hn hp ny bn vng vi nhit hn so vi PTZ t do trong khong nhit kho st, do cng pic ch gim i nhiu ch khng mt, ng thi cng ca pic cng ph thuc vo t l HP--Cyd c trong hn hp.

Nh vy, trong hn hp vt l vi manitol v HP--Cyd, PTZ bn vng vi nhit hn, t l HP--Cyd c trong hn hp cng ln, PTZ cng bn vng. Kt qu ny cng ph hp vi nghin cu ca M.El-Badry v cng s v nh hng ca t l HP--Cyd trong hn hp (omeprazol:HP--Cyd) n n nh ca omeprazol (mt cht trong nhm benzimidazol)[6]. 3.2. Kt qu nh gi nh hng ca HP--Cyd n n nh ca ch phm ng kh PTZ

Bng 1: Thnh phn hn hp vt l

Thnh phn M1 M2 M3

Manitol (mg) 120 120 120

PTZ (mg) 50 50 50

HP--Cyd (mg) 50 150

T l PTZ: HP--Cyd 1:0 1:1 1:3

Hnh 1: ng biu din phn tch nhit vi sai (DSC) ca PTZ (1), manitol (2), HP--Cyd (3),

hn hp M1 (4), M2 (5) v M3 (6).

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Trn c s kt qu thu c t phng php DSC vi hn hp vt l, tin hnh bo ch ch phm ng kh PTZ vi mu CT233 c HP--Cyd v mu CT234 khng c HP--Cyd. Mi m ng kh 200 l theo cng mt quy trnh. 3.2.1. nh gi bng cm quan v bng phng php HPLC

Sn phm sau khi ng kh c theo di trong iu kin cng bc, c th: Cc mu c trong t 1000C. Mi 2 gi, kim tra hnh thc, mu sc ca bnh thuc; mu sc, c ca dung dch pha li vi 2,5ml nc ct pha tim; hm lng hot cht v t l tp cht c xc nh bng phng php HPLC. Kt qu c trnh by trong bng 2 v 3: Bng 2: nh hng ca HP--Cyd n hnh thc bt v dung dch pha li ca ch

phm ng kh PTZ

Thi gian

Bt ng kh Dung dch pha li CT233 CT234 CT233 CT234

0 gi Hnh bnh thuc, trng, mn

Hnh bnh thuc, trng, mn

Trong, khng mu

Trong, khng mu

Sau 2 gi



Trong, khng mu

Trong, khng mu

Sau 4 gi


Hnh bnh thuc, vng, khng mn

Trong, khng mu

Trong, mu vng nht

Kt qu bng 3 cho thy: sau 2 gi iu kin cng bc (nhit 1000C), hm lng PTZ trong

sn phm pha ch theo cng thc 233 gim t hn so vi sn phm ng kh theo cng thc 234 (3,05% v 5,87%), trong khi t l tp cht b phn hy cng t hn (0,71% - tng 10,8 ln v 1,32% - tng 14,6 ln). Sau 4 gi, tng ng l (5,05% v 8,19%) v (1,56% - tng 26 ln v 4,15% - tng 50,1 ln). 3.2.2. nh gi bng phng php DSC

Cc sn phm ng kh theo cng thc 233 v 234 c nh gi bng phng php DSC vi cc iu kin c ghi phn 2.3.1. Kt qu c trnh by trong hnh 2:

Bng 3: nh hng ca HP--Cyd n n nh ca ch phm ng kh PTZ

Thi gian Hm lng (%) PTZ T l (%) tp cht CT233 CT234 CT233 CT234

O gi 103,01 104,92% 0,06% 0,09% Sau 2 gi 99,51 99,05% 0,71% 1,32% So snh Gim 3,50% Gim 5,87% Tng 10,8 ln Tng 14,6 ln

Sau 4 gi 97,96% 95,73% 1,56% 4,51% So snh Gim 5,05% Gim 8,19% Tng 26 ln Tng 50,1 ln

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Kt qu hnh 2 cho thy: ng nhit ca sn phm ng kh theo cc cng thc 233, 234 u cho pic thu nhit ti khong t 160-170OC tng ng vi nhit nng chy manitol (cng tng ng l-90mW v -138mW) v ngay sau khi nng chy l mt trng thi ta nhit khng c trng (tng quan vi nhit phn hy ca PTZ - 190OC) vi cng tng ng 34mW v 80mW, chng t sau khi ng kh PTZ khng cn dng tinh th m chuyn sang dng v nh hnh. Tuy nhin, cng ca cc pic trn ng nhit ca sn phm ng kh theo cng thc 233 u thp hn cng cc pic tng ng trn ng nhit ca sn

phm ng kh theo cng thc 234. Nh vy, kt qu t phng php DSC ph hp vi kt qu thu c t phng

php HPLC, c hai phng php u cho thy bt ng kh theo cng thc 233 bn vng vi nhit hn bt ng kh theo cng thc 234, iu ny chng t rng HP--Cyd lm tng n nh vi nhit ca ch phm ng kh PTZ.

Kt qu ny cng ph hp vi nghin cu ca mt s tc gi trn th gii v nh hng ca HP--Cyd vi mt s cht trong nhm benzimidazol [2],[3],[4],[6].

T kt qu thu c, cc m tip theo s dng HP--Cyd lm t c n nh ch phm ng kh PTZ. 3.3. Kt qu nghin cu nh hng ca t l HP--Cyd n n nh ca ch phm ng kh PTZ

Tin hnh ng kh vi cng mt quy trnh k thut cc cng thc c cng t dc kim, t dc to khung, t dc chng oxy ha, nhng s dng lng HP--Cyd khc nhau:

Bng 4: Khi lng HP--Cyd s dng trong cc cng thc ch phm ng kh PTZ

Cng thc 3061 3063 871 872 873 3182 2872 1971 1972 1973 1974 1975 Khi lng HP--Cyd

s dng (mg) 50 100 150 200 300 350 400 450 600 750 900 1050

3.3.1. nh gi bng cm quan v bng phng php HPLC

Hnh 2: ng biu din phn tch nhit vi sai (DSC) ca PTZ (1), manitol (2), HP--Cyd (3), bt ng kh ca cng

thc 234 (4) v 233 (5)

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V cm quan - Cc mu pha ch theo cng thc 1972; 1973; 1974; 1975 khng ng lnh,

khng thnh hnh bnh thuc hoc bnh thuc c b mt khng mn, c tch lp, khng xp (cng thc 1971). V vy, cc sn phm sau ng kh theo cc cng thc ny khng tin hnh nh gi cc ch tiu khc.

- Sn phm sau khi ng kh theo cc cng thc 3061; 3063; 871; 872; 873; 3182; 2872 c hnh bnh thuc p, mn, cho nn tip tc nh gi cc ch tiu khc nh hm lng hot cht, t l tp cht. Tin hnh lo ha cng bc vi cc iu kin nh phn 2.3.4. Kt qu c trnh by trong bng 5 v hnh 3:

Bng 5: Hm lng (%) PTZ v t l (%) tp cht ca ch phm ng kh PTZ trong cc cng thc

Thi gian CT3061 CT3063 CT871 CT872 CT873 CT3182 CT2872

Hm lng (%)

pantoprazol

0 gi 100,01 99,89 106,70 102,30 106,70 100,08 107,6 Sau 2 gi 95,51 96,38 103,49 99,28 104,14 97,95 105,55 So snh (gim %)

4,50 3,51 3,21 3,02 2,56 2,13 2,15

Sau 4 gi 93,96 94,33 102,20 98,30 103,19 97,06 104,48 So snh (gim %) 6,05 5,56 4,50 4,00 3,51 3,02 3,12

T l (%) tp cht

0 gi 0,12 0,13 0,12 0,12 0,09 0,08 0,09 Sau 2 gi 1,21 1,13 1,01 0,99 0,59 0,43 0,51 So snh (ln)

10,08 8,69 8,42 8,25 6,56 5,38 5,67

Sau 4 gi 2,51 2,00 1,71 1,53 1,01 0,89 0,91 So snh (ln) 20,92 15,38 14,25 12,75 11,22 11,13 10,11

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(a) (b)

Hnh 3: th biu din s ph thuc ca t l tp cht v gim hm lng PTZ vo lng HP--Cyd trong thnh phn ch phm ng kh PTZ

(a). gim hm lng PTZ sau 2 v 4 gi (b). T l tp cht trong bt ng kh sau 2 v 4 gi

Kt qu trn cho thy vi cng thnh phn trong cng thc, n nh ca ch phm ng kh PTZ 40mg ph thuc vo lng HP--Cyd s dng. Lng HP--Cyd s dng cng nhiu n nh ca ch phm ng kh PTZ cng cao. Vi lng HP--Cyd s dng l 50mg/l, sn phm ng kh sau 2 gi nhit 1000C, hm lng PTZ trong sn phm pha ch theo cng thc 3061 gim (4,5%), t l tp cht (1,21% - tng 10,08 ln), sau 4 gi, tng ng l (6,05%) v (2,51% - tng 20,92 ln). Trong khi nu lng HP--Cyd s dng l 350mg/l, sn phm ng kh sau 2 gi nhit 1000C, hm lng PTZ trong sn phm pha ch theo cng thc 3182 ch gim (2,13%), t l tp cht (0,43% - tng 5,38 ln), sau 4 gi, tng ng l (3,02%) v (0,89% - tng 11,13 ln). Tuy nhin, nu tip tc tng lng HP--Cyd s dng trong cng thc th khng nhng n nh ca ch phm ng kh PTZ khng tng (nh sn phm bo ch theo cng thc 2872) m cn khng ng kh c (nh dung dch pha ch theo cc cng thc 1972; 1973; 1974; 1975) hoc hnh thc xu (khng thnh hnh bnh thuc, khng xp) nh sn phm ng kh theo cng thc 1971. 3.3.2. nh gi bng phng php DSC

Cc sn phm ng kh c nh gi bng phng php HPLC ng thi cng c nh gi bng phng php DSC vi cc iu kin c ghi phn 2.3.1. Kt qu c trnh by trong hnh 4:

0

0,5

1

1,5

2

2,5

3

0 50 100 150 200 250 300 350 400 450

Lng HP--Cyd s dng

T l

Sau 2 gi

Sau 4 gi

0

1

2

3

4

5

6

7

0 50 100 150 200 250 300 350 400 450

Lng HP--Cyd s dng

% h

m l

Sau 2 gi

Sau 4 gi

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Kt qu hnh 4 cho thy: ng nhit ca sn phm ng kh theo cc cng thc 3061; 871; 873; 3182 u khng c pic phn hy ca PTZ, tuy nhin cng ca cc pic thu nhit khc nhau ph thuc vo lng HP--Cyd c trong cng thc, trong bt ng kh theo cng thc 3182 (s dng HP--Cyd 350mg/l) c cng pic thp nht.

Nh vy, kt qu t phng php DSC cng ph hp vi kt qu thu c t phng php HPLC, c hai phng php u cho thy bt ng kh theo cng thc 3182 s dng HP--Cyd 350mg/l bn

vng vi nhit hn c, iu ny cng ph hp vi kt qu nghin cu nh hng ca t l HP--Cyd n n nh ca PTZ trong hn hp vt l.

4. Kt lun

T nhng kt qu nghin cu, thc nghim thu c, rt ra mt s kt lun:

- HP--Cyd lm tng n nh PTZ. Tuy nhin, mc n nh ph thuc vo lng HP--Cyd c trong cng thc. Trong nghin cu ny, ch phm ng kh PTZ 40mg n nh hn c khi s dng 350mg/l HP--Cyd.

- Kt qu nh gi n nh ca ch phm ng PTZ bng phng php HPLC ph hp vi kt qu t phng php DSC.

Summary

Hydroxypropyl--cyclodextrin increase the stability of pantoprazole in lyophilized powder. However, the stability depends on the proportion of hydroxypropyl--cyclodextrin in the formulation. The research indicates that, pantoprazole lyophilized powder is the most stability with hydroxypropyl--cyclodextrin 350mg/vial. The pantoprazole stability were evaluated by method DSC and HPLC.

A formulation consists of pantoprazole sodium sesquihydrate, sodium hydroxide, mannitol, disodium EDTA, hydroxypropyl--cyclodextrin with reasonable proportion and water for injection were improved. Pantoprazole lyophilized powder was prepared in laboratory scale, each batch comprised 200 vials.

Ti liu tham kho

1. A. Kristl (2009), Acido-basic properties of proton pump inhibitors in aqueus solutions, Drug Dev. Ind. Pharm., 35, p. 114-117.

Hnh 4: ng biu din phn tch nhit vi sai (DSC) ca PTZ (1), manitol (2), HP--Cyd (3), bt ng kh theo cng thc 3061

(4), 871 (5), 873 (6) v 3182 (7).

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2. Ana Figueiras et al (2007), Solid-state characterization and dissolution profiles of the inclusion complexes of omeprazole with native and chemically modified beta-cyclodextrin, Eur. J. Pharm. Biopharm., 67, p.531539.

3. Ana Figueiras et al (2009), In vitro evaluation of natural and methylated cyclodextrins as buccal permeation enhancing system for omeprazole delivery, Eur. J. Pharm. Biopharm., 71, p. 339345.

4. Ana Figueiras et al (2010), The role of l-arginine in inclusion complexes of omeprazole with cyclodextrins, AAPS PharmSciTech., 11, 1, p. 233-240.

5. Chantal Holvoet et al (2007), Development of an omeprazole parenteral formulation with hydroxypropyl-beta-cyclodextrin, Pharm. Dev. Technol., 12, p.327336.

6. M.El-Badry et al (2010), Effects of Kollicoat IR and hydroxypropyl-beta-cyclodextrin on the dissolution rate of omeprazole from its microparticles and enteric-coated capsules, Pharm. Dev. Technol., 15, 5, p.500-510.

7. R.P.Raffin et al (2007), Gastro-resistant microparticles containing sodium pantoprazole: Stability studies and in vivo anti-ulcer activity, The Open Drug J., 1, p. 28-35.

8. R.P.Raffin et al (2010), Pharmacokinetics evaluation of soft agglomerates for prompt delivery of enteric pantoprazole-loaded microparticles, Eur. J. Pharm. Biopharm., 74, p.275-280

9. T.Comoglu et al (2008), Development and in vitro evaluation of pantoprazole-loaded micropheres, Drug Del., 15, p. 295-298.

10. Wei He et al (2010), Influences of sodium carbonate on physicochemical properties of lanzoprazole in designed multiple coating pellets, AAPS PharmSciTech., inpress.

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NGHIN CU NH LNG ITRACONAZOL TRONG CH PHM VIN NANG BNG PHNG PHP VI SINH

Trn Trnh Cng

t vn

Itraconazol l mt tc nhn khng nm, c hot tnh ph rng, thuc nhm triazol. Vin nang itraconazol (ITZ) ung, hm lng 100mg, c sn trn th trng Vit Nam: sporal (Janssen, sn xut ti Thi Lan), itcon (n ), Fungex (Lin doanh), Khi hm lng ITZ thp hn so vi ghi trn nhn, ha tr liu s khng t hiu qu iu tr, gy hi cho sc khe bnh nhn.

Cc nghin cu nh lng ITZ bng phng php vi sinh (Bioassay) trc y ch yu ch yu l xy dng v thm nh phng php nh lng ITZ trong huyt thanh bng Bioassay v HPLC, cha thy c ch phm vin nang. Phng php Bioassay c th cho chng ta bit cc thay i nh, tinh vi ca dc cht, khng th chng minh c bng phng php ha l. Bioassay cho php nh gi hot lc ca ITZ, mt yu t quan trng trong vic kim nghim khng sinh.

xc nh hot lc khng sinh bng phng php khuch tn trn thch c th p dng m hnh ng thng song (Parallel-line model) [1, 4, 5, 6, 8] v m hnh ng chun [2, 3].

Mc tiu ca phng php ny l xy dng v thm nh mt phng php vi sinh xc nh hot lc ca ITZ trong cc ch phm vin nang thng mi.

Nguyn liu v phng php

Cc thuc th v nguyn liu: Chun tham chiu ITZ nhp khu t n . Cc vin nang cng sporal (100mg) ca hng dc phm Janssen, sn xut ti Thi Lan, mua ngoi th trng. Nc ct 2 ln c dng trong phn tch. Dimethylsulfoxid (DMSO) tiu chun phn tch, Trung Quc.

Pha dung dch chun:

Dung dch chun m 160g/ml: cn chnh xc 8mg chun tham chiu, pha vo bnh nh mc 50ml bng DMSO. Pha tip bng DMSO c dung dch 16 g/ml. T dung dch ny pha long bng nc ct tit trng c dung dch 1,6 g/ml, c dng pha long gp i k tip ti 0,1 g/ml.

Cc nng chun: 1,6 (S1); 0,8 (S2); 0,4 (R: nng tham chiu); 0,2 (S4) v 0,1 (S5) g/ml.

Pha dung dch th gc ca vin nang 160 g/ml tng t chun ti nng 0,4 g/ml (tng t nng tham chiu R). Cc nng chun v th c pha ngay trc khi th.

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Chng th: Candida albicans ATCC 10231 c nui cy trn mi trng thch nghing SDA 2%, bo qun 4oC. Trc khi s dng, cy truyn chng sang mi trng thch nghing SDA mi, 28oC, trong 24h. Sau giai on ny mt lng nh nm men c chuyn vo dung dch nc mui sinh l tit trng v truyn qua (trn my quang ph UV-VIS 1900) c hiu chnh ti 85%, 520nm (tng ng 1-5x106 CFU/ml) [2, 9]. Pha long tip hn dch trong 15ml SDA (c un chy 45oC), t c nng cui cng 1-5 x 105 CFU/ml.

Cc a Petri kch thc 100 x 20mm, gm mt lp nn (8ml mi trng SDA) c cho vo cc a trc khi th to s quan st d dng vng c ch. Sau khi lp nn ng rn, lp chng (15ml) c rt ln b mt ca lp nn. Cho thch ng rn nhit phng 10-15 pht. Sau c cc ging ng knh 6mm 6 im trn a Petri theo s th 5x1 (hnh 1) [2, 3]. Nm a Petri c dng trong php th, tin hnh th ng thi nng tham chiu R vi mi nng chun hoc cc nng th. 60l ca mi nng chun hoc th c cho vo cc ging ring bit. Cc a c 28oC, 24h. o vng c ch bng thc kp caliper ( chnh xc 0,01 mm). Cc a th c lp li 3 ln (tng ng vi 15 a trong mi ln th), cho 9 kt qu o ca cc nng chun S1, S2, S4, S5 v mu th T. Nng R c th 45 ln hiu chnh cc s liu trong tt c cc a.

Hnh 1: S th 5x1

Cc iu kin thc nghim nu trn vi cc thng s sau:

- Thi gian : 24h.

- Nhit : 37oC.

- Nng chng 1-5x105 CFU/ml.

Hiu chnh vng c ch (IZc) bng nng tham chiu R

Trung bnh ca tt c cc ln o ca nng R (trong tt c cc a) c dng hiu chnh cc gi tr ca cc vng c ch trong mi a ring bit. hiu chnh s liu thu c, ng dng phng trnh (Lima et al., 2009): IZc = IZ + (RA - Rs), trong :

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- IZc : gi tr vng c ch c hiu chnh.

- IZ: gi tr trung bnh ca vng c ch ca mu chun hoc mu th trong a nghin cu.

- RA: trung bnh ca cc gi tr vng c ch ca nng R trong tt c cc a (45 gi tr).

- Rs: trung bnh ca cc gi tr vng c ch ca nng R, trong a nghin cu (9 gi tr).

Phn tch s liu bng vic xy dng ng chun t l gia log10 nng itraconazol v ng knh vng c ch; phng trnh ng cong t c bng vic phn tch hi qui.

Cc nng ca dung dch th c xc nh bng phng trnh ng chun.

Thm nh phng php

Phng php th vi sinh c thm nh bng vic nh gi tuyn tnh, chnh xc v ng theo cc bc c m t trong cc hng dn Q2 (R1) ca IHC:

- tuyn tnh: 5 nng chun tham chiu c th (1,6; 0,8; 0,4; 0,2 v 0,1 g/ml). ng chun t l gia log10 nng ITZ v K (ng knh) vng c ch c thit lp. Cc s liu thu c qua phn tch hi qui bng phng php bnh phng ti thiu.

- chnh xc: chnh xc trong ngy c nh gi bng phn tch s liu ca 6 ln lp li ca cc dung dch ITZ (n=6), 100% ca nng th (0,4g/ml). Tng t, chnh xc khc ngy c nh gi vo 2 ngy tip theo (n=12). Nng ITZ trong cc mu vin nang v lch chun tng i (R.S.D.) c tnh ton.

- ng: ng: c xc nh bng vic thm cc lng bit ca chun tham chiu ITZ (0,1; 0,2 v 0,3 g/ml) vo mt dung dch th (0,2 g/ml) vo u qu trnh phn tch, tng ng vi 75; 100 v 125% nng th (0,4 g/ml). Mi mc th c chun b 3 ln v c th nh m t trn. Xc nh phn trm tm li ca ITZ.

Kt qu v tho lun

Xy dng phng php: trong nghin cu ny chng ti xy dng v thm nh phng php th vi sinh, xc nh hm lng ITZ trong ch phm vin nang. S chun ha cc iu kin thc nghim l yu t quan trng t c cc kt qu lp li v ng tin cy: lp nn, nhit th (37oC), thi gian (24h), chng nm th (C. albicans ATCC 10231), nng chng (1-5x105 CFU/ml). Thit k thc nghim s dng 6 ging/a nh s trn to ra lch thp hn, do cc vng c ch c hiu chnh qua vng c ch R. Nng chng 1-5 x 105 CFU/ml cho vng c ch sc nt nht, khi so snh vi cc nng chng 103 v 104 CFU/ml hoc ln hn (

27


cho cc vng c ch khng r nt). Cc vng c ch thu c r nt trong iu kin th. Cc ging lp li 3 ln cho cc K (ng knh) vng c ch khc nhau trong phm vi 1mm. Trung bnh cc gi tr vng c ch hiu chnh ca cc nng chun l 20,0 (S1); 18,13 (S2); 15,13 (R); 13,25 (S4) v 11,18mm (S5). ng chun t l c xy dng vi gi tr trung bnh r2 = 0,9939. DMSO nng cui cng (10%) khng nh hng ti s pht trin ca chng C. albicans ATCC 10231.

Thm nh phng php Bioassay

tuyn tnh: t c mi quan h tuyn tnh (r2= 0,9939) gia cc nng ITZ v K vng c ch trong gii nng nghin cu. Cc d liu phn tch hi qui c trnh by bng 1. Phng trnh hi qui tuyn tnh i din cho ITZ l y = 0,133x 2,4642.

Bng 1: Cc s liu tuyn tnh thu c ca itraconazol

Thng s Kt qu phn tch hi qui

H s hi qui 0,9939 dc (slope) 0,133

H s chn (intercept) -2,4642 Di nng (g/ml) 0,10 - 1,6

S im kho st 5

chnh xc: c th hin bng lch chun tng i (R.S.D.). Trong php th chnh xc trong ngy (n=6), hm lng trung bnh ca ITZ l 103,38 % (R.S.D. = 3,2 %). chnh xc khc ngy (n=12), hm lng trung bnh t c l 104,65% (R.S.D.= 3,85%). Cc gi tr R.S.D. t c cho thy phng php t chnh xc yu cu (bng 2).

Bng 2: Hm lng ca ITZ trong cc mu vin nang Sporal xc nh bng phng php Bioassay (n=6)

Ln th Hm lng (%) 1 2 3 4 5 6

106,1 104,68 108,0 98,5 103,0 100,0

Ga tr trung bnh lch chun

R.S.D. (%)

103,38 3,31 3,2

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ng: c kho st bng thc nghim b sung cht chun, 3 mc nng , lp li 3 ln (n=9). Phn trm tm li thay i t 104,3%-106,0% (bng 4). khm ph trung bnh 104,9% m bo ng ca phng php.

Bng 4: tm li ca ITZ trong thc nghim b sung chun nh gi ng ca phng php

Mu Nng b sung (g/ml)

Nng tm li (g/ml)*

% tm li

1 0,1 0,1055 105,5 2 0,2 0,209 104,5 3 0,3 0,310 103,3

* Trung bnh ca 3 ln xc nh

Mc du c s khc bit nh nng b sung 0,1%, nhng cc kt qu cho thy phng php bioassay c tin cy. Cc x nghip dc phm c th tin hnh p dng ng thi vi HPLC, khi xc inh ITZ. y l mt bc quan trng cho vic kim tra hot lc ca cc cht ha tr liu khng nm, mc du loi phng php th ny khng c mt trong cc dc in chnh thc (D Brazil 1988; D Anh 2007; D M 2007). i vi cc khng sinh khng khun, cc dc in khuyn co thc hin c Bioassay v HPLC, do cc php th ny c tc dng b sung cho nhau.

Bioassay c mt vai tr quan trng trong sn xut v kim sot cht lng cc thuc khng sinh (Salgado et al., 2006). Ngoi ra phng php ny cn c chi ph thp, n gin hn so vi HPLC trong vic xc nh ITZ trong ch phm vin nang. Tuy nhin tim nng c chp nhn ca phng php ny cn c nghin cu k thm v so snh cc kt qu thu c vi mt phng php c chnh cc cao hn l HPLC.

Kt lun

Xc nh hm lng ITZ trong ch phm vin nang, bc u cho thy c tin cy, khi s dng liu chng 1-5 x 105 CFU/ml, chng C. albicans ATCC 18804 v thi gian 24h, 37oC, trn gii nng 0,1-1,6 g/ml.

Ti liu tham kho

1. Cardoso S.G. et al. (2000), Microbiological assay for terbinafine hydrochloride in tablets and creams, International Journal of pharmaceutics Vol. 203, p. 109-113

2. Lima P.M. et al. (2009), Determination of ketoconazole in capsules by high-performance liquid chromatography and microbiological assay, J. of AOAC international, Vol. 92, No. 4

29


3. Queiroz K.M. et al. (2009), Comparison of microbiological assay and HPLC-UV for determination of fluconazole in capsules, Brazilian J. of Pharm. Sciences, Vol. 45, No. 4

4. Schmidt C.A. et al. (2008), Development and validation of an agar diffusion assay for determination of ceftazidime in pharmaceutical preparations, J. of AOAC international vol. 91, No.1

5. Souza M.J. et al. (2007), Development of a microbiological assay to determine the potency of ceftiofur sodium powder, J. of AOAC international vol. 90, No. 6

6. Staub I. et al. (2005), Microbiological assay of ketoconazole in shampoo, Int. J. of Pharm., Vol. 292, p. 195-199.

7. Validation of analytical procedures (2005): Text and methodology Q2 (R1)-CHR harmonized tripartite guideline. International conference on harmonization of technical requirements for registration of Pharmaceuticals for human use, p. 1-13

8. Vaucher L.C. et al. (2006), Microbiological assay for the determination of teliothromycin in tablets, J. of AOAC international, Vol. 89, No. 5

30


VI CU KIM SOT GII PHNG - KT DNH NIM MC V NG DNG TRONG CI THIN HP THU ACICLOVIR

QUA NG TIU HA V Th Thu Giang, Phm Th Minh Hu, Nguyn Thu Hin

1. t vn

ng ung l ng a thuc vo c th ph bin nht hin nay. Tuy nhin hp thu thuc qua ng tiu ha kh phc tp, trong nhiu trng hp c ch hp thu cha hon ton sng t. Hp thu thuc thay i dc theo ng tiu ha, thng gim dn cui ng tiu ha, chu s tc ng ca nhiu yu t. Thc t thuc thng c hp thu ch yu mt vng nht nh trn ng tiu ha. Phn ln cc thuc c hp thu tng i nhanh phn u rut non, chm v khng hon ton phn cui ng tiu ha. V vy kim sot gii phng vng hp thu ti u trong ng tiu ha l mt trong nhng cch ci thin hp thu v SKD ca thuc.

Vi cu KSGP - KDNM c kh nng lu gi thuc trn b mt nim mc ng tiu ha trong vng hp thu ti u nh gp phn ci thin hp thu thuc qua ng tiu ha. V vy bo ch h kim sot gii phng thuc kt dnh nim mc (KSGP - KDNM) c th l bin php tt ci thin sinh kh dng ng ung cho nhng thuc c tnh thm km nh aciclovir.

2. i cng v h kt dnh sinh hc

2.1. Khi nim kt dnh sinh hc v kt dnh nim mc

Thut ng kt dnh sinh hc (KDSH) dng ch s hnh thnh cc lin kt gia hai b mt sinh hc hoc gia mt b mt sinh hc v mt b mt tng hp. Trong cc h KSGP KDNM thut ng ny c dng ch s kt dnh gia cc polyme t nhin hay tng hp vi cc m nh nim mc ng tiu ha... Trong thc t, cc lin kt kt dnh c th c hnh thnh gia polyme vi lp mng ny hoc mng t bo hoc kt hp c hai loi lin kt.

2.2. C ch v qu trnh kt dnh sinh hc

Cho n nay, c ch KDSH cha hon ton sng t. V c bn hu ht cc tc gi u thng nht s KDSH xy ra nh hai nhm lin kt ha hc v vt l.

- Lin kt ha hc: quan trng v mnh nht l cc lin kt ng ha tr hnh thnh gia chui polyme v cc phn t protein trn b mt t bo biu m, tip theo l cc lin kt ion v cc lin kt hydro. Tuy nhin cc lin kt loi ny thng gp phi cc ro cn m cc nh nghin cu cn tnh n l (1) lp mng nhy l ro cn polyme tip xc trc tip vi mng t bo; (2) Lp t bo biu m thng bong ra theo chu k 3 4 ngy; (3) Tng hp v mt sinh hc cha c nghin cu k.

31


- Lin kt vt l: l cc tng tc phn tn u cc chui polyme trong lp cht nhy. Tc khuch tn vo lp cht nhy ph thuc vo s linh hot ca chui polyme v h s khuch tn ca c hai thnh phn polyme v cht nhy. Cng lc lin kt ph thuc vo mc thm su ca cc chui polyme, nc, thi gian tip xc, chiu di v mc linh hot ca chui polyme, lc ht van der Wal...

Qu trnh KDSH xy ra qua ba giai on nh sau:

- Polyme thm t v trng n tip xc vi biu m sinh hc.

- Polyme KDSH, cht nhy thm v phn tn vo nhau.

- Hnh thnh cc lin kt ha hc v vt l.

2.3. Polyme kt dnh sinh hc

Yu cu i vi polyme KDSH:

c kh nng KDSH, cc polyme cn c cc tnh cht sau:

- C cc nhm chc ha hc c kh nng to lin kt hydro (carboxyl, hydroxyl, amid, sulfat)

- Mang in tch b mt.

- Trng lng phn t ln.

- Cc chui polyme c tnh linh hot cao.

- Sc cng b mt cho php tri rng b mt tip xc vi mng sinh hc.

Mt s polyme kt dnh sinh hc thng c s dng

Chitosan l sn phm kim ha ca polyme kitin c di do trong t nhin, c th tng hp v phn hy sinh hc nn l mt t dc rt hu dng. Do c khi lng phn t ln, chitosan khng thm qua t bo hoc vo c h tun hon m ch tng tc vi cc t bo: KDSH mnh, ci thin hp thu qua khe h lin bo do ni lng lin kt cht ch gia cc t bo nh tng tc gia nhm amin mang in tch dng ca chitosan v cc protein b mt mang in tch m ca lin kt khe h lin bo lm tng hp thu thuc m khng gy hi cho t bo [5], [7]. Chitosan cn c kh nng kim sot gii phng thuc ko di, bo v dc cht khi tc ng ca cc enzym nh pepsin, trypsin trong dch tiu ha [11]. Chnh v vy chitosan c nhiu nh khoa hc quan tm s dng trong cc nghin cu ci thin hp thu dc cht qua ng tiu ha. Mt s dn cht ca chitosan nh N-trimethyl chitosan (TMC) v chitosan- 4-thiobutylamidin (TBA) l nhng cht c kh nng ci thin hp thu rt tt cho cc thuc dng theo ng ung. Nhiu nghin cu cho thy dn cht chitosan thiol ha nh chitosan-TBA l polyme c kh nng KDSH mnh hn hn chitosan. Nguyn nhn c bn l do s hnh thnh cu ni disulfid gia polyme v glycoprotein mng nhy. Ngoi ra, chitosanTBA cn lm tng vn chuyn qua khe k t bo khi kt hp vi

32


glutathion do cht ny c ch protein tyrosin phosphatase thng qua hnh thnh mt lin kt disulfid vi cystein ca enzym dn ti ni lng lin kt gia cc t bo. y chnh l mt c ch lm tng hp thu cc cht thn nc c tnh thm km qua k t bo. Cc chitosan thiol ha bm dnh tt trn nim mc dn ti glutathion lu trn b mt t bo nhiu hn nn ci thin hp thu qua k t bo [6], [1].

Carbomer (Polycarbophil, Carbopol): l mt polyme ca acid acrylic c lin kt cho bi cc allyl ether ca saccarose hoc pentaerythritol. Cc polyme ny c kh nng trng n mnh, KDSH v to phc vi ion Ca2+ thnh rut nn ni lng lin kt khe h lin bo lm tng hp thu dc cht theo ng ny. Ngoi ra Carbomer cn c kh nng c ch hot tnh ca mt s enzym trong ng tiu ha nh trypsin v carboxypeptidaze B nn hn ch thy phn cc thuc bn cht protein [5].

Dn cht cellulose: Bao gm HPMC (hydroxy propylmethyl cellulose), HPC (hydroxy propyl cellulose) y l cc polyme thuc nhm hydrogel hay cn gi l cht kt dnh m t v chng cn m mi kt dnh c. n nh khi kh, trng n trong mi trng thn nc, cc si lin kt cho trong phn t to thnh ct lu tr thuc [8]

3. Vi cu kim sot gii phng thuc v kt dnh nim mc

Vi cu KSGP KDNM l nhng tiu phn c cu to mt khi ng nht ging nh nhng ct (matrix) mang thuc. Cht mang dng trong bo ch vi cu thng l mt hay hn hp polyme c kh nng KSGP dc cht v KDSH.

C ch kt dnh nim mc ca cc vi cu thuc nhm ny c m t theo s hnh 1.

Vi cu KSGP KDNM Polyme KDSH trng n

Hnh 1. C ch kt dnh ca vi cu KSGP KDNM

T dc khc

Polyme KDSH

KDNM

Dc cht

33


Trong hu ht cc nghin cu, vi cu KSGP KDNM c bo ch theo phng php bc hi dung mi theo s hnh 2.

Hnh 2. Cc bc bo ch vi cu KSGP KDNM theo phng php bc hi dung mi

4. Mt s nghin cu bo ch vi cu aciclovir KSGP KDNM nhm ci thin hp thu qua ng tiu ha

Trong hn hai chc nm qua, ACV l thuc c la chn hng u trong iu tr cc bnh do virus herpes simplex nhm 1 v 2. Ngoi ra ACV cn c tc dng trong iu tr cc bnh do nhim cc virus Varicella-Zoster, Epstien-barr, Cytomegalo v c ch virus vim gan B. Tuy nhin, do t tan trong nc (1,3 mg/ml 25oC [4]) v lipid nn nhiu dng bo ch ca ACV khng th m bo nng thuc thch hp ti ni iu tr [2]. Ngoi ra, ACV c tnh thm km, thn du v c khi lng phn t thp (< 300) nn c hp thu ch yu qua khe h lin bo [5], [7], ch chim mt t l rt nh so vi ng vn chuyn, thi gian lu ca thuc ti v tr hp thu ti u l phn u ng tiu ha ti t trng, hng trng ngn [3], [10] do SKD ng ung thp v khng n nh (10 - 30%) [9]. ci thin SKD ca ACV, hng nghin cu bo ch h KSGP KDNM ng tiu ha cha c mt s nh khoa hc ng dng kh thnh cng.

Dhaliwal S. v cng s [3] nghin cu bo ch vi cu kt dnh nim mc duy tr gii phng ACV d dy. Chitosan, chitosan thiol ha, Carbopol 71G v Methocel

Ethanol

Du parafin v cht din hot

Nh tng nc / du Bc hi dung mi

Dc cht

Polyme

34


K15M c s dng lm polyme kt dnh sinh hc. Cc vi cu c bo ch bng k thut lin kt cho nh tng (emulsion-chemical crosslinking technique) vi tc nhn lin kt cho l gluteraldehyd. Nang gelatin cha bt ACV c ha tan in vitro sau 1 gi l 90.53.6% trong khi nang cha vi cu kt dnh nim mc ko di qu trnh gii phng dc cht ti 12 gi (78.83.9). Kt qu nh gi kh nng kt dnh nim mc cho thy vi cu chitosan thiol ha c thi gian lu khu vc t trng v hng trng chut tt hn c (8.00.8 h). Nghin cu dc ng hc trn chut cho thy cc vi cu kt dnh sinh hc c kh nng duy tr nng ACV trong huyt tng mc c th xc nh c ti 24 gi trong khi dung dch ACV ch duy tr c 5 gi. Vi cu chitosan thiol ha c kh nng ci thin hp thu ni tri hn c, AUC024 (1,090 51 ng h/ml) cao gp gn 4 ln so vi dng dung dch ACV (28128 ng h/ml). Nh vy kt qu nghin cu chng t vic ko di gii phng dc cht t cc vi cu kt dnh nim mc ci thin ng k SKD ng ung ca ACV do ko di c thi gian lu ca thuc phn trn ng tiu ha.

Vi cu ACV kt dnh nim mc s dng t dc to ct l EC v polyme kt dnh nim mc l Carbopol 974P NF c Tao Y. v cng s [10] bo ch bng phng php bc hi dung mi nh tng. Hnh thi ca vi cu c quan st bng knh hin vi quang hc v knh hin vi in t qut. Nghin cu kh nng gii phng in vitro v SKD ng ung ca vi cu ACV trn chut cho thy qu trnh gii phng dc cht b tc ng mnh bi pH mi trng v t l Carbopol trong vi cu. Tc gii phng ACV t vi cu trong mi trng pH 1,3 v 7,4 nhanh hn hn trong mi trng pH 3,6. Trn 95% dc cht c gii phng trong mi trng pH 1,3 v 7,4, ch c 75% ACV c gii phng trong mi trng pH 3,6 sau 6 gi, qu trnh gii phng dc cht tip tc ko di ti 12 gi. Nguyn nhn c th do kh nng to gel ca Carbopol v tan ca ACV thay i trong cc mi trng pH khc nhau. Khi t l Carbopol trong vi cu tng th tc gii phng ACV trong mi trng pH 3,6 cng tng ln. EC c s dng vi vai tr ct ko di gii phng dc cht nh thuc tnh khng tan trong nc v tnh thm thp cn Carbopol l polyme tan trong nc nn to thnh cc knh thn nc bn trong vi cu gip dc cht khuch tn ra ngoi lm tng tc gii phng dc cht ng thi l tc nhn kt dnh sinh hc lu thuc ti v tr hp thu. Kt qu nghin cu kh nng kt dnh nim mc chng t vi cu ch to ko di thi gian lu thuc trong ng tiu ha chut. Nghin cu v cc thng s dc ng hc cho thy nng nng ACV trong huyt tng tng i n nh v ko di 8 gi sau khi cho chut ung vi cu. Cc thng s AUC0t v MRT ca vi cu ACV (6055.9 ng h/mL v 7.2 h) cao hn hn so vi hn dch ACV (2335.6 ng h/mL v 3.7 h) (P < 0.05) chng t SKD ca ACV tng mnh do vi cu ACV kt dnh nim mc ko di thi gian lu thuc trong ng tiu ha.

Tham kho cc nghin cu i trc, chng ti nghin cu bo ch vi cu ACV KSGP KDNM theo phng php bc hi dung mi nh tng vi thnh phn cng thc c bn nh sau:

35


- Aciclovir

- Carbopol 934P (Cb): kt dnh nim mc

- Ethylcellulose (EC): kim sot gii phng

- Aerosil: chng dnh

- thanol tuyt i (EtOH): dung mi pha ni

- Du parafin lng: pha ngoi

- Span 80: cht nh ha

Vi cu ACV c tin hnh bo ch theo phng php bc hi dung mi nh tng. Cb v EC c phn tn trong EtOH, ngm trong 8 gi to gel ng nht. phn tn ACV v Aerosil vo gel to hn dch ng nht. Ha tan Span 80 vo du parafin sau rt nhanh hn dch ACV/polyme vo dung dch du parafin cha cht nh ha, kt hp lc phn tn bng my khuy tc cao nht 1000 vng/pht vi siu m trong 3 pht to nh tng. Tip tc khuy t vi tc 900 vng/pht nhit phng trong vng 12 gi bc hi EtOH. Gn, lc ht chn khng thu c vi cu. Ra 3 ln bng ether du ha loi ht du parafin tha. Lm kh vi cu trong bnh ht chn khng trong vng 12 gi.

Tin hnh bo ch vi cu ACV theo 12 cng thc th hin trong bng 1 (du parafin va 500 ml).

Bng 1. Cng thc vi cu ACV KDNM GPKD

Cng thc ACV (g)

EC (g)

Cb (g)

Aerosil (g)

EtOH (ml)

Span 80 (g)

CT1 2,25 3,36 1,12 0,10 50 12,50 CT2 2,25 3,75 0,75 0,10 50 12,50 CT3 2,25 3,92 0,56 0,10 50 12,50 CT4 2,25 4,05 0,45 0,10 50 12,50 CT5 3,00 3,75 0,75 0,10 50 12,50 CT6 1,80 3,75 0,75 0,10 50 12,50 CT7 2,25 3,75 0,75 0,10 40 12,50 CT8 2,25 3,75 0,75 0,10 60 12,50 CT9 2,25 3,75 0,75 0,05 50 12,50 CT10 2,25 3,75 0,75 0,14 50 12,50 CT11 2,25 3,75 0,75 0,10 50 15,00 CT12 2,25 3,75 0,75 0,10 50 10,00

36


Hnh 3. Hnh nh vi cu bo ch theo cng thc CT2

Kt qu kho st cho thy vi cu ACV bo ch theo 12 cng thc c kch thc phn b kh u, trn 80 % vi cu thu c c kch thc trong khong 0,60 1,18 mm. Hiu sut ch to v t l vi cu ha u ph thuc vo thnh phn cng thc.

Cc cng thc bo ch u cho hiu sut to vi cu v t l vi cu ha trn 60 %. T l Cb/EC v trong cng thc gim t 1/3 n 1/9, hiu sut ch to v t l vi cu ha u gim xung. Ngc li, t l ACV v EtOH tng lm tng hiu sut ch to v t l vi cu ha. Span 80 v Aerosil gim lm gim hiu sut to vi cu nhng t l vi cu ha li tng ln.

nh gi kh nng gii phng in vitro ca vi cu bo ch trong mi trng nc ct. Kt qu th hin trong bng 2.

Bng2. Phn trm gii phng ACV t vi cu theo thi gian ca 12 cng thc

(n = 3)

Mu vi cu

Phn trm gii phng ACV t vi cu theo thi gian 1 gi 2 gi 3 gi 4 gi 5 gi 6 gi 7 gi 8 gi

CT1 35,25 48,89 67,16 79,21 88,62 92,14 94,04 101,21 CT2 23,35 35,08 47,84 63,93 73,12 79,77 87,39 94,51 CT3 31,02 43,66 54,60 60,89 75,31 76,86 85,58 89,24 CT4 19,69 21,87 22,78 23,47 33,01 33,37 34,39 35,41 CT5 15,12 31,80 43,69 52,40 59,55 65,74 70,97 75,41 CT6 18,66 41,05 58,46 70,86 80,47 87,89 93,57 97,80 CT7 28,74 34,87 47,54 63,78 74,33 81,65 87,68 93,62 CT8 15,26 35,88 49,70 60,28 68,71 75,17 80,28 86,57

37


CT9 22,21 48,45 69,18 83,99 94,83 101,81 - - CT10 22,86 55,68 73,32 87,36 97,75 105,01 - - CT11 10,96 24,32 34,62 42,28 49,14 54,97 59,77 64,37 CT12 33,81 61,51 78,30 88,32 94,36 97,28 98,78 99,51

Mc d thnh phn cng thc khc nhau th kh nng kim sot gii phng dc cht khc nhau nhng nhn chung 12 mu vi cu bo ch u c kh nng gii phng ACV ko di. Mu CT4 c tc gii phng chm nht, sau 8 gi ch gii phng c 35,41%. Nguyn nhn c th do EC l polyme khng tan trong nc, ng vai tr chnh kim sot gii phng dc cht nn khi t l EC tng cao nht th tc gii phng dc cht chm nht. Cc mu CT9 v CT10 c tc gii phng nhanh nht, ch ko di qu trnh gii phng dc cht ti 6 gi. Cc mu vi cu cn li u c kh nng ko di qu trnh gii phng ACV t 8 n trn 12 gi.

La chn cc mu vi cu CT1, CT8, CT3 v CT4 c t l cc polyme Cb/EC ln lt l 1/3, 1/5, 1/7 v 1/9 nh gi kh nng KDNM ng tiu ha trn 16 chut cng c cn nng t 300 350 g ( nhn i, cho ung nc t do trong 24 gi trc khi tin hnh th nghim). Cho chut ung 100 ht vi cu bng ng xng v chiu vi 5 ml nc. Sau 2 hoc 6 gi gy cht chut bng ete v phu thut xc nh t l vi cu cn kt dnh trn nim mc d dy v rut non. Kt qu c th hin trong bng 3.

Bng 3. T l vi cu ACV KSGP KDNM cn kt dnh d dy v rut non chut sau khi ung (n = 2)

Thi gian % vi cu ACV cn lu li trn ng tiu ha chut

V tr CT1 CT8 CT3 CT4

Sau 2 gi D dy 73 81 73 77

Rut non 0 0 0 0 Tng 73 81 73 77

Sau 6 gi D dy 35 28 26 34

Rut non 41 60 46 44 Tng 76 88 82 78

Kt qu nghin cu cho thy sau 2 gi, trn 70% cc mu vi cu nghin cu u vn kt dnh hu ht d dy v khng tm thy vi cu no rut non. Cho ti tn thi im 6 gi sau khi ung, vn cn trn 25 % lng vi cu cn c kt dnh trn nim mc d dy, trong mu CT1 c t l cn lu gi trn nim mc d dy chut ln nht (35%). Do hn ch v s lng chut th nghim, s ln lp li cha nhiu nn s khc bit v kh nng KDNM gia cc mu vi cu bo ch cha c s khc bit r rt. Tuy vy tng s vi cu cn kt dnh trn nim mc ng tiu ha ti v tr hp thu (d dy v rut non) ca cc mu nghin cu u trn 75 %.

38


Cc kt qu nghin cu v kh nng gii phng dc cht in vitro v KDNM ng tiu ha in vivo trn chut chng t c kh nng KSGP ACV v ko di thi gian lu ca thuc ti v tr hp thu ti u trn nim mc ng tiu ha ca vi cu bo ch.

Ti liu tham kho

1. Bernkop-Schnurch A., Guggi D., et al. (2004), "Thiolated chitosans: Development and in vitro evaluation of a mucoadhesive, permeation enhancing oral drug delivery system", J Control Release, 94(1), pp. 177-186.

2. Cortesi R. , Esposito E. (2008), "Acyclovir delivery systems", Expert Opin Drug Deliv, 5(11), pp. 1217-1230.

3. Dhaliwal S., Jain S., et al. (2008), "Mucoadhesive microspheres for gastroretentive delivery of acyclovir: In vitro and in vivo evaluation", AAPS J, 10(2), pp. 322-330.

4. Luengo J., Aranguiz T., et al. (2002), "Preliminary pharmacokinetic study of different preparations of acyclovir with beta-cyclodextrin", J Pharm Sci, 91(12), pp. 2593-2598.

5. Merzlikine A., Rotter C., et al. (2009), "Effect of chitosan glutamate, carbomer 974p, and edta on the in vitro caco-2 permeability and oral pharmacokinetic profile of acyclovir in rats", Drug Dev Ind Pharm, 35(9), pp. 1082-1091.

6. Roldo M., Hornof M., et al. (2004), "Mucoadhesive thiolated chitosans as platforms for oral controlled drug delivery: Synthesis and in vitro evaluation", Eur J Pharm Biopharm, 57(1), pp. 115-121.

7. Shah P., Jogani V., et al. (2008), "In vitro assessment of acyclovir permeation across cell monolayers in the presence of absorption enhancers", Drug Dev Ind Pharm, 34(3), pp. 279-288.

8. Sudhakar Y., Kuotsu K., et al. (2006), "Buccal bioadhesive drug delivery--a promising option for orally less efficient drugs", J Control Release, 114(1), pp. 15-40.

9. Sweetman S.C., et a. (2009), Martindale 36, Pharmaceutical Press, pp. 862-864, 911.

10. Tao Y., Lu Y., et al. (2009), "Development of mucoadhesive microspheres of acyclovir with enhanced bioavailability", Int J Pharm, 378(1-2), pp. 30-36.

11. Wu Z. H., Ping Q. N., et al. (2004), "Hypoglycemic efficacy of chitosan-coated insulin liposomes after oral administration in mice", Acta Pharmacol Sin, 25(7), pp. 966-972.

39


NGHIN CU BO CH NANO NH TNG NH MT DICLOFENAC V NH GI KH NNG GII PHNG

DC CHT IN VITRO CA CH PHM ng Th Hin, V Ngc Mai, Nguyn Trn Linh

Tm tt

Nano nh tng diclofenac c bo ch bng cch dng siu m nh ha pha du vo pha nc cha dc cht, cc cht din hot, dung mi v cht lm tng hp thu. S nh hng ca cc thnh phn to nn nano nh tng cng nh dng tn ti ca dc cht (natri diclofenac hay acid diclofenac) ti hnh thc bn ngoi, c tnh hin vi v kh nng gii phng dc cht in vitro ca nano nh tng c kho st. Thit k th nghim c in v mng neural nhn to c s dng phn tch d liu. 22 mu nano nh tng c bo ch theo bng thit k th nghim. Loi v lng cc thnh phn trong nano nh tng c la chn c lp. Phn trm dc cht gii phng ti thi im 1, 2, 3, 4, 5, 6 gi c coi l cc bin ph thuc. S thay i ca cc bin u vo nh hng c ngha ti hnh thc bn ngoi, c tnh hin vi v kh nng gii phng dc cht in vitro ca nano nh tng.

T kha: diclofenac, nano nh tng, thit k th nghim, mng neural nhn to.

Abstract

Diclofenac nanoemulsions were prepared by ultrasonification emulsifying oil phase into water phase containing active ingredient, surfactants, solvents and penetration enhancers. The influences of nanoemulsion components as well as derivatives of active ingredient (diclofenac sodium or diclofenac acid) on the appearance, microscopic properties and in vitro drug releases from nanoemulsions were evaluated. The classical experimental design and artificial neural network were used for data analysis. As model formulations, 22 kinds of nanoemulsions were prepared. The types and amounts of components were selected as independent variables. The percentages of active ingredient released at 1, 2, 3, 4, 5 and 6 hours were considered as dependent variables. The changes in the types and amounts of all components influenced significantly the release rates of active ingredient from nanoemulsions as well as their microscopic properties.

Keywords: diclofenac, nanoemulsion, experimental design, artificial neural network.

1. t vn

Nghin cu h cp thuc ti mt l mt trong nhng lnh vc ht sc hp dn nhng cng y thch thc vi cc nh bo ch. Cc ch phm thuc nh mt vi cc h cp

40


thuc thng dng c sinh kh dng thp v hiu qu iu tr cha cao; c hiu qu p ng iu tr, ngi bnh phi nh mt liu thuc ln hoc phi nh nhiu ln mi ngy [2], [3], [4], [7].

Diclofenac l dn cht ca acid phenylacetic thuc nhm thuc chng vim khng steroid, c ch chn lc COX 2 hn COX 1, c tc dng chng vim, gim au v h st mnh Diclofenac dng cho mt trn th trng mi ch c dng dung dch vi nng 0,1%, thuc tc dng trong thi gian rt ngn, t nng nh trong iu tr khong 30 pht sau nh v b thi tr hon ton ra khi c th trong 1 gi v vy bnh nhn mi ch nh iu tr mi ngy phi nh thuc t nht 3-5 ln [1], [5].

Nano nh tng l mt h cp thuc mi, c chng minh l rt thch hp dng cho mt; n c hnh thnh bi s phn tn ca du nc, c n nh bng s tham gia ca cht din hot, cht ng din hot [6], [8]. Vi nhiu u im hn dng thuc nh mt dung dch thng thng, nano nh tng c la chn trong thit k nghin cu ca chng ti nhm bo ch mt dng thuc nh mt mi cho diclofenac c kh nng duy tr s gii phng thuc hng nh trn gic mc, ko di thi gian tc dng ca thuc, thm su hn vo cc lp trong cu trc ca mt nhm tng hiu lc iu tr v gim s ln dng thuc mi ngy.

2. Nguyn liu v phng php nghin cu

2.1. Nguyn liu

Acid diclofenac (Trung Quc), Natri diclofenac (Trung Quc), Tween 80 (Singapore), Cremophor EL (Singapore), Span 80 (Singapore), Isopropyl myristat (Singapore), Labrafac PG (Canada), Miglyol (BASF), Transcutol HP (Canada), Acid boric (Trung Quc), Acid phosphoric (Merck), natri dihydrophosphat (Trung Quc), dinatri hydophosphat (Trung Quc), acid citric (Trung Quc), natri hydroxyd (Trung Quc), Methanol (Merck), Glycerin (Trung Quc), Nc ct (Vit Nam)


2.2.1. Phng php bo ch nano nh tng

- Pha nc: nc, glycerin, h m, cc cht din hot tan trong nc: un nng 70-750C.

- Pha du: du, cht din hot tan trong du, Transcutol HP, dc cht: un nng 65-700C.

- Kt hp 2 pha, siu m 5 pht.

- Lc qua mng cellulose acetat 0,2 m.

2.2.2. nh lng diclofenac c trong nano nh tng

41


Hm lng diclofenac gii phng t nano nh tng v dc cht c trong nano nh tng c xc nh theo phng php sc k lng hiu nng cao. H thng sc k bao gm ct Alltech C8 (250 mm 4,6 mm, 5 m); pha ng l hn hp methanol v dung dch m phosphat pH 2,5 vi t l 75 : 25; th tch tim mu: 20 L, tc dng: 1mL/pht; detector mng quang diod, bc sng = 276nm.

2.2.3. nh gi mc gii phng dc cht

S dng h thng gii phng thuc qua mng Hanson Research, vi iu kin:

- Mng cellulose acetat 0,2 m.

- Mi trng khuch tn: dung dch m phosphat pH 7,4.

- Th tch mi trng khuch tn: V = 7 mL.

- Nhit mi trng khuch tn: 370C.

- Din tch b mt mng khuch tn: 1,76 cm2.

- Tc khuy: 400 vng/pht.

- Lng mu em th: 1 ml (tng ng vi 1 mg natri diclofenac; 0,93 mg acid diclofenac)

Ly mu: Trong 6 gi, c mi gi ly mu 1 ln. Mi ln ly 1 mL, ng thi b sung thm 1 mL mi trng khuch tn mi. Mu ly ra c em phn tch ngay bi h thng sc k lng hiu nng cao c m t mc 2.2.2.

2.2.4. Thit k th nghim

M hnh thit k th nghim truyn thng v mng neuron nhn to c s dng lm cng c xc nh mc nh hng ca cc t dc ti t l gii phng diclofenac. D liu c my tnh phn tch vi s tr gip ca phn mm MODDE 8.0 (Umetrics Inc., USA) v INFORM 3.2 (Intelligensys Ltd., UK).

2.2.5. Xc nh hnh thi, kch thc ht nano nh tng

D liu c chp hnh bi s tr gip ca my TEM (Vin v sinh dch t Trung ng).

3. Kt qu v bn lun

3.1. Xy dng cng thc thc nghim

Trong cc nghin cu s b, xy dng cng thc nano nh tng vi cc thnh phn c bn nh sau: diclofenac (acid diclofenac, natri diclofenac: 0,1% (kl/kl), glycerin (5%) Tween 80 (hoc Cremophor EL, Tween 80/Cremophor EL (1/1)), Span 80, Labrafac PG (hoc isopropyl myristat), Transcutol HP, m borat (phosphat, citrat)

42


(va 100% kl/kl). Cc bin c lp v khong bin thin ca n c trnh by trong bng 1.

Bng 1. Cc bin c lp

Thnh phn Khong bin thin Nng Span 80 0,5 1,5 (%) Loi cht din hot thn nc Tween 80

Cremophor EL Tween 80/Cremophor EL (1/1)

Nng cht din hot thn nc 3 5 (%) Loi dung mi du Labrafac PG

Isopropyl miristat Nng dung mi du 3 5 (%) Transcutol HP 1 2 (%) Loi dung dch m Borat

Phosphat Citrat

Nng dung dch m 0,1 0,2 M (va 100 %)

pH 6,5 7,5

Cc bin ph thuc l phn trm diclofenac hoc natri diclofenac c gii phng sau 1, 2, 3, 4, 5, 6 gi. Bng thit k th nghim cho bi Modde 8.0 gm 22 th nghim (vi mi thnh phn hot cht khc nhau). Cc th nghim sau c tin hnh. Kt qu c phn tch bng mng neuron nhn to (tch hp trong INFORM 3.2) nhm nh gi nh hng ca cc bin c lp ti cc bin ph thuc.

3.2. Kt qu v phn tch cc yu t nh hng

3.2.1. bn ca nano nh tng

Nano nh tng c bo ch theo phng php c m t trong mc 2.2.1. Tt c cc mu u c kim tra bn bng cch luc si mu trong 1 gi v quan st s tch lp (Bng 2).

Bng 2: bn ca nano nh tng

Mc

S tch lp Acid diclofenac (s mu)

Natri diclofenac (s mu)

1 Tch lp hon ton 5 5 2 Tch lp cha hon ton (pha nc trong, pha du c) 7 8 3 Tch lp khng hon ton (pha du v nc u c) 8 6 4 Bn khng b tch lp 2 4

43


3.2.2. nh hng ca cc thnh phn v loi thnh phn ti s gii phng ca nano nh tng

Hnh 1. nh hng ca isopropyl myristat v Tween 80 ti mc gii phng dc cht t nano nh tng (Span 80 = 1,0%, Transcutol HP = 1,5%, m

phosphat 0,15 M, pH = 7,0)

Hnh 1 ch ra nh hng ca Tween 80 v isopropyl myristat ti mc gii phng dc cht t nano nh tng. N cho thy nu loi dung mi pha du l isopropyl myristat tng v lng Tween 80 gim th s lm tng mc gii phng. Hnh 2 ch ra khi lng cht din hot thn nc gim v lng Span 80 gim th phn trm dc cht gii phng sau 6 gi tng. iu ny c th thy rng vi hot cht natri diclofenac c tan trong pha nc ln hn DC v bn thn n cng l mt cht din hot yu gip cho s hnh thnh nano nh tng mt cch d dng do vy khi tng t l Tween 80, Span 80 ch lm tng nht ca nano nh tng nn lm chm tc khuch tn dc cht ra khi h.

% gii phng NaDC

Sau 3 gi

Isopropyl myristat (%) Tween 80 (%)

44


Hnh 2: nh hng ca lng cht din hot thn nc v Span 80 ti phn trm gii phng dc cht sau 6 gi (isopropyl myristat = 4,0%, Transcutol HP = 1,5%,

m citrat 0,15 M, pH = 7,0)

Hnh 3: nh hng ca Cremophor EL v Miglyol n phn trm gii phng dc cht sau 6 gi (Span 80 = 0,75%, Transcutol HP = 1,0%, citrat 0,15 M, pH 7,0)

Span 80 (%) Tween 80/Cremorphor EL

(%)

% NaDC gii phng sau 6 gi

Cremophor EL (%)

Miglyol (%)

% Diclofenac gii phng sau 6 gi

45


Nhn xt: khi lng pha du tng v lng cht din hot thn nc gim th phn trm dc cht gii phng sau 6 gi tng. iu ny c th gii thch l do acid diclofenac thn du hn so vi natri diclofenac chnh v vy n phn tn phn ln trong pha du ca nano nh tng, v vy lng pha du cng ln cng ha tan ti a dc cht do lng pha du tng ng nhin lng dc cht gii phng tng; mt khc cht din hot thn nc t c vai tr h tr trong vic hnh thnh nano nh tng cha hot cht diclofenac m ch lm tng nht gy cn tr qu trnh gii phng dc cht ra khi h.

3.2.3. Xc nh hnh thi, kch thc ht nano nh tng (TEM)

Hnh 4. nh chp TEM ca nano nh tng cha natri diclofenac.

Cu trc nano nh tng c cha hot cht natri diclofenac qua chp TEM cho thy c s phn b git ng u nhau v kch thc ht nm trong khong t 20 250 nm. iu ny c th cho thy vai tr va l hot cht va l cht din hot yu ca natri diclofenac, n gip phn tch cc ht nano nh tng nh lc y ion v th cc ht tch ri hn nhau v c kch thc kh ng u.

46


Hnh 5. nh chp TEM ca nano nh tng cha acid diclofenac.

Cu trc nano nh tng c cha hot cht l acid diclofenac qua chp TEM cho thy c s phn b git khng ng u nhau v kch thc ht kh ln nm trong khong t 100 1000 nm. S phn b khng ng u, s lng cc ht tch ri nhau rt t cho thy tnh thn du rt cao ca hot cht, cc cht din hot vi lc y ion yu khng th lm phn tch cc git to cu trc dng ht.

4. Kt lun

Kt qu nghin cu cho thy rng khi lng v cc loi thnh phn tham gia cu trc nano nh tng, loi nguyn liu u vo ca dc cht (mui natri hay dng acid) u nh hng ti t l gii phng ca hot cht ra khi nh tng. Qua chp TEM cho thy nano nh tng cha hot cht natri diclofenac cho kch thc ht ng u nhau, nm trong khong t 20 250 nm ph hp vi khong kch thc git quy nh ca cu trc nano nh tng.

Ti liu tham kho

1. Chuasuwan B., Binjesoh, Polli J. E., Zhang H, Amidon G. L., Junginger H. E., Midha K. K., Shah V. P., Stavchansky S., Dressman J. B., Barends D. M. (2009), Bioweiver monographs for immediate release solid oral dosage forms: Diclofenac sodium and diclofenac potassium, Journal of pharmaceutical sciences, Vol 98, No 4, pp.1206 1219.

2. Chein Y. W., Cabana B. E., Mares S. E. (1982), Ocular controlled release drug administration, Drugs and the pharmaceutical sciences, Vol. 14, pp.13-55.

47


3. Hussein O. Ammar, Salama H. A., Ghorab M., Mahmoud A. A. (2009), Nanoemulsion as a Potential Ophthalmic Delivery System for Dorzolamide hydrochloride, AAPS PharmSciTech, Vol 10, No3, pp. 808 819.

4. Hughes PM, Mitra AK (1993), Overview of ocular drug delivery and iatrogenic ocular cytopathologies , Ophthalmic drug delivery systems, p. 1-27.

5. Mims.com 6. Shah P, Bhalodia D, Shalat P (2010), Nanoemulsion: A pharmaceutical review,

Sys Rev Pharm, Vol 1, Issue 1, pp. 24-32. 7. Sieg JW, Robinson JR (1977), Verhice effect on ocular drug bioavailability II:

evaluation of pilocarpine, J Pharm Sci, 66; pp.1222 - 1228. 8. Sharma N, Bansal M, Visht S, Sharma PK, Kurkarni (2010), Nanoemulsion: A

new concept of delivery system, Chronicles of Young Scientists, pp. 2-6.

48


NGHIN CU BO CH VIN NN CAPTOPRIL GII PHNG KO DI BNG PHNG PHP DP NHIU LP

Hong Ngc H, Phm Th Minh Hu

1. t vn

Captopril l mt thuc thuc nhm c ch men chuyn c s dng tng i ph bin trong iu tr tng huyt p v suy tim sung huyt, c c im l d tan trong nc nhng khng bn trong mi trng kim [1].

Nghin cu bo ch vin captopril gii phng ko di c thc hin nhiu trong v ngoi nc nh vin bao, ct bn rn, vin gii phng theo nhp, vi nang [2].

Bo ch vin nhiu lp thng c nghin cu vi cc mc ch kim sot gii phng dc cht khc nhau nh: vin 3 lp gii phng ko di theo ng hc bc 0, h gii phng nhanh/chm, gii phng theo m hnh sinh hc... [3].

ti nhm mc tiu nghin cu bo ch vin nn captopril 50 mg gii phng ko di 12 gi bng phng php dp nhiu lp.

2. Nguyn liu, thit b v phng php nghin cu

2.1. Nguyn liu, thit b

Nguyn liu: Captopril (Trung Quc), HPMC 4000 (JJ Degusca), gm xanthan(XG) (M), ethyl cellulose (EC) (Trung Quc), lactose (Trung Quc), magnesi stearat (MgSt) (Trung Quc). Cc nguyn liu u t tiu chun USP/BP.

Thit b: Cn phn tch Satorius, cn k thut Satorius, my o pH, my th ha tan t ng Vankel-Varian, my dp vin tm sai Korsch.


2.2.1. Bo ch vin nn captopril

Vin captopril gii phng ko di c bo ch vi hm lng 50 mg.

Vin mt lp c bo ch bng phng php dp thng.

Vin 3 lp c dp thng vi phng php nh sau: Cho ln lt lp 1, 2 vo v nn nh, cho lp 3 vo v dp.

S dng chy bng, ng knh 8mm, cng nm trong khong 5-7 kP.

2.2.2. Th ha tan ca vin captopril

Vin nn captopril c th ha tan vi cc iu kin nh sau: thit b cnh khuy, tc quay 50 vng/pht, mi trng l 900 ml dung dch HCl 0.01N, nhit

49


37 0.5 , 60 pht ht mu mt ln, nh lng bng phng php o quang ti bc sng 215nm.

2.2.3. nh gi ng hc gii phng ca vin captopril

S dng phn mm S-Plus 8.0, Excel 2007 nh gi ng hc gii phng vin nn captopril theo cc m hnh: ng hc bc 0, Higuchi, Hixson-Crowell, Korsmeyer-Peppas. S dng gi tr AIC (Akaikes Information Criterion) nh gi mc ph hp vi cc m hnh ng hc.

Mt s c im ca cc m hnh ng hc: [4]

ng hc bc 0: Tc gii phng dc cht khng ph thuc no nng ca n.

ng hc Higuchi: M t qu trnh gii phng dc cht bng con ng khuch tn.

ng hc Hixson-Crowell: M t gii phng dc cht ha tan khi c s thay i din tch b mt hay ng knh tiu phn hay vin nn.

ng hc Kormeyer-Peppas. M t c ch gii phng t h ct polymer khi c ch gii phng cha r rng hay c nhiu c ch.

Trong :

Qt l tng lng dc cht gii phng ti thi im t.

Qo l lng dc cht ban u.

t l thi gian.

Ko, KH, KHC, Km ln lt l hng s ng hc bc 0, Higuchi, Hixson-Crowell, Korsmayer-Peppas.

Vi ng hc Korsmayer Peppas (H hnh tr):

n=0.45: Gii phng theo nh lut Fick.

0.45


3.1. nh hng ca t dc to ct n gii phng dc cht t vin mt lp

3.1.1. HPMC 4000 v XG

nh gi nh hng ca loi t dc to ct v lng t dc to ct n kh nng gii phng dc cht, vin mt lp ct HPMC 4000 hoc XG c bo ch vi thnh phn nh trong bng 1.

Bng 1: Cng thc vin mt lp captopril ct HPMC4000/XG

Mu Captopril (mg) HPMC4000 (mg) XG (mg) MgSt (mg) T1

50

47 3 T2 95.5 4.5 T3 144 6 T4 47 3 T5 95.5 4.5 T6 144 6

Hnh 1: % dc cht gii phng t cc vin nn captopril c t l HPMC 4000 v

XG khc nhau

t l 1:1 th khng c s khc bit v gii phng dc cht t ct HPMC 4000 vi XG. Vi t l dc cht:t dc 1:2, 1:3 th HPMC 4000 kim sot gii phng dc cht tt hn XG. Khi tng dn t l HPMC 4000 th tc v mc gii phng dc cht u gim. Vi XG th li khng c s thay i ng k v gii phng dc cht khi dng vi cc t l khc nhau (hnh 1).

3.1.2. Phi hp EC vi HPMC

Cc cng thc vin mt lp trn tuy s dng t l HPMC 4000/XG kh cao nhng giai on u dc cht gii phng nhanh nn tin hnh bo ch vin mt lp phi hp HPMC 4000 vi EC (bng 2).

51


Bng 2: Vin 1 lp captopril ct HPMC 4000 phi hp EC

Captopril (mg) HPMC (mg) EC (mg) MgSt (mg)

T7 (E10)

50

129.9 14.4

6 T8 (E25) 108 36 T9 (E50) 72 72 T10 (E75) 36 108

Hnh 2: % dc cht gii phng t vin mt lp captopril ct HPMC 4000

phi hp EC

Khi thay HPMC bng nhng lng EC tng dn th tc v mc gii phng dc cht u tng. Nguyn nhn l do EC l mt polymer s nc, khng c kh nng ht nc, captopril rt d tan trong nc nn EC mi mn nhanh khin dc cht gii phng nhanh (hnh 2).

3.2. Nghin cu bo ch vin captopril gii phng ko di bng cch dp nhiu lp

Do kh nng kim sot gii phng dc cht ca cc cng thc vin mt lp cn thp mc d dng t l polymer kh cao nn tin hnh bo ch vin captopril gii phng ko di bng phng php dp nhiu lp vi cng thc nh trong bng 3.

Bng 3: Cng thc vin ba lp captopril ct HPMC 4000/XG

Lp Captopril (mg) HPMC (mg) XG (mg) MgSt

T11 1 48.5 1.5 2 50 47 3 3 48.5 1.5

T12 1 48.5 1.5 2 50 47 3 3 48.5 1.5

52


Trong trng hp vin 3 lp, do b mt trn v di ca lp gia b che bi lp polymer nn giai on u dc cht ch yu gii phng t cnh bn ca vin. Giai on sau, khi lp 1, 3 b hydrat ha v trng n cho php dc cht gii phng nhanh hn (hnh 3).

Hnh 3: % dc cht gii phng t vin nhiu lp captopril ct HPMC

4000/XG, so snh vi vin mt lp

Do XG c thn nc, mc v tc hydrat ha mnh hn HPMC 4000 [5]

nn cng thc T12 gii phng dc cht nhanh hn cng thc T11 (d T1 v T4 gii phng gn nh nhau). Tuy nhin lng dc cht gii phng sau 12h gim ng k so vi vin 1 lp cng thnh phn (tng ng vi mu T3 v T6). Nguyn nhn chnh l do dc cht tp trung lp gia nn qung ng khuch tn ln hn so vi trng hp vin 1 lp.

Hnh 4: % dc cht gii phng gia cc thi im t vin nhiu lp captopril ct

HPMC 4000/XG, so snh vi vin mt lp cng thnh phn

Bn cnh , khi so snh vi vin 1 lp cng thnh phn th lng dc cht gii phng gia cc thi im ca vin 3 lp ng u hn (hnh 4).

% dc cht gii phngphng

Thi gian (h)

53


3.2.1. nh hng ca thnh phn lp gia n gii phng dc cht

nh gi nh hng ca thnh phn lp gia n gii phng dc cht, vin ba lp c lp 1, 3 ging cng thc T11 c bo ch vi thnh phn lp gia nh bng 4.

Bng 4: Thnh phn lp gia vin ba lp captopril vi lp ngoi ging nhau

Captopril (mg) HPMC (mg) XG (mg) EC MgSt T13

50

35.25 11.75

3

T14 23.5 23.5 T15 11.75 35.25 T16 0 47 T17 35.25 11.75 T18 23.5 23.5 T19 35.25 11.75

Hnh 5: % dc cht gii phng gia cc thi im t vin ba lp khi thay nhng t l nht nh HPMC 4000 lp gia bng XG.

Khi s dng lp gia vi t l khc nhau ca HPMC v XG th c im gii phng dc cht ca cc vin khng khc nhau nhiu, ch yu ch khc nhau 2 gi u (do XG v HPMC 4000 trng n khc nhau) (hnh 5).

Khi thay nhng t l khc nhau ca t dc to ct lp gia bng EC, kt qu ha tan ca cc mu T17, T18, T19 nh sau:

Thi gian (h)

% dc cht gii phng

54


Hnh 6: % dc cht gii phng gia cc thi im t vin ba lp khi c EC

lp gia

Khi thay th 25% ct lp gia bng EC (T17, T19) kh nng kim sot gii phng

dc cht l tt nht. Vi trng hp thay 50% ct lp gia bng EC (T18) th kt qu cng t, tuy nhin tng lng dc cht gii phng n thi im ch t khong 80%. Do EC l mt polymer khng tan trong nc, mt bn ca lp gia dc cht ha tan nn EC b mi mn nhanh. Nhng vi hai mt b che bi lp 1 v 3 th EC li lm chm qu trnh thm ca mi trng vo lp gia, gim tc khuch tn dc cht v do lm ng u gii phng giai on sau.

Nh vy vai tr ca EC khi chim khong 25% t dc lp gia khng nhng c th kim sot, lm ng u lng dc cht gii phng gia cc thi im m cn lm tng lng dc cht gii phng sau 12h (cc cng thc vin 3 lp m lp 1,3 ch c HPMC v MgSt, khng c EC lp gia sau 12 u ch gii phng c khong 80% cn cng thc T17 85% t T19 t 86.65%).

3.2.2. nh hng ca thnh phn lp ngoi n gii phng dc cht

a. nh hng ca EC

Bo ch vin 3 lp c thnh phn lp trong ging nh cng thc T12, lp ngoi thay nhng t l nht nh HPMC 4000 bng EC.

Bng 5: Thnh phn lp ngoi phi hp HPMC vi EC

HPMC (mg) EC (mg) MgSt (mg) T20 43.65 4.85

1.5 T21 36.375 12.125 T22 24.25 24.25

Thi gian (h)

% dc cht gii phng

55


Hnh 8: % dc cht gii phng t vin ba lp captopril khi phi hp HPMC

vi EC lp ngoi

Trong khong 4h u, lng dc cht gii phng t cc mu khng khc nhau nhiu. Tuy nhin trong cc gi sau c s khc bit gia cc cng thc.

Do lp ngoi ch c EC, HPMC 4000, MgSt m khng c cht d tan trong nc (lactose, captopril) nn EC rt kh b n mn dn n h qu l kh nng km hm gii phng dc cht tt nhng li khin cho lng dc cht gii phng sau 12h thp (Trng hp cng thc T22 do lng EC khng nhiu nn th gii phng khng khc nhiu so vi T12) (hnh 8).

b. nh hng ca lactose

Bo ch cc vin 3 lp c thnh phn lp trong ging cng thc T12 (50mg captopril, 47mg XG v 3% MgSt) v lp ngoi nh sau:

Bng 6: Thnh phn lp ngoi khi phi hp XG v lactose

Kt qu ha tan cho thy bt u khong t gi th 3-4 tr i t l dc cht gii

phng gia cc thi im cao hn so vi T12. iu ny c th gii thch do lactose tan nhanh lm tng cc knh dn nc trong cc lp 1 v 3 nn lm tng gii phng dc cht. Khng nhng vy tng lng dc cht gii phng sau 12h cng tng ng k so vi cng thc T13 (hnh 9).

XG (mg) Lactose (mg) MgSt (mg) T24 46.075 2.425

1.5 T25 43.65 4.85

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Hnh 9: % dc cht gii phng t vin ba lp phi hp XG lp ngoi bng

nhng t l lactose khc nhau

3.3. nh gi ng hc gii phng dc cht

Vi hu ht cc cng thc quy lut gii phng u ph hp vi m hnh Korsmayer-Peppas vi gi tr n nm trong khong 0.45-0.89. Duy nht ch c trng hp vin 1 lp ct XG ph hp vi ng hc Higuchi (bng 7).

Bng 7: Tm tt phn tch ng hc cc cng thc

Mu

Zero Hixson_Crowell Korsmayer-Peppas Higuchi

AIC AIC n AIC AIC

T3 0.959 38.470 101.085 0.6341 24.082 38.2987 T6 0.898 66.405 105.443 0.53 67.858 38.907 T11 0.984 66.304 98.954 0.78 15.826 49.697 T12 0.952 46.678 102.404 0.672 33.377 45.96 T17 0.992 43.483 99.000 0.818 1.489 51.793 T19 0.995 42.560 99.360 0.8595 -0.343 54.606

4. Kt lun

Nghin cu cho thy bo ch vin 3 lp vi thnh phn EC khong 25% ct lp gia c th kim sot gii phng dc cht d tan trong nc tng i hng nh. Thnh phn lp ngoi thay i nh hng nhiu n gii phng dc cht, c bit l giai on sau.

Ti liu tham kho:

1. Martindale 35 S.o.t.R.P.S.o.G. Britain, Editor. 2007, Pharmaceutical Press. 2. Abubakr O. Nur, J.S.Z., Recent progress in sustained/controlled oral delivery of

captopril: an overview. International journal of Pharmaceutics, 1999. 194: p. 139-146.

57


3. Shajanhan Abdul, S.S.P., A flexible technology for modified release of drugs: multi layered tablets. Journal of Controlled Release, 2004. 97: p. 393-405.

4. Paulo Costa, J.M.S.L., Review: Modeling and comparison of dissolution profiles. European journal of pharmaceutical sciences, 2011. 13: p. 123-133.

5. Mohammad Mahiuddin TalukdarCorresponding Author Contact Information, A.M., Patrick Rombaut and Renaat Kinget, Comparative study on xanthan gum and hydroxypropylmethyl cellulose as matrices for controlled-release drug delivery I. Compaction and in vitro drug release behaviour International journal of Pharmaceutics, 1995. 129: p. 233-241.

58


M HNH TH GII PHNG IN VITRO CA DNG THUC TI CH GII PHNG TI I TRNG

Nguyn Thu Qunh

Test th ha tan l phng php c s dng nhiu nht nh gi kh nng gii phng ca cc dng thuc ung bao gm c dng thuc ti ch gii phng ti i trng. Mt bc pht trin hp l l s dng phng php th ha tan nh gi ng hc gii phng, cc tc ng ca thnh phn cng thc, qui trnh sn xut, pH v cc c im ca ng tiu ha n c tnh gii phng ca thuc lm sng t c ch gii phng thuc, m bo s sn xut nht qun gia cc l m, c th thay th th in vivo. iu ny i hi phng php phi c s khc bit, lp li, chnh xc v quan trng hn l phi tng t mi trng ng tiu ha. Hin nay, cc test th ha tan thng p dng theo USP nh gi kh nng gii phng ca cc dng thuc ci tin dng theo ng ung, tuy nhin nhc im ca phng php l cha nh gi chnh xc mt s dng thuc ng ung mi, nn vic thm mt s ci tin vo test th ha tan USP l cn thit.

Dng thuc gii phng ti ch i trng nhm nng cao hiu qu iu tr v gim tc dng ph ca thuc nh lm tng nng thuc ti v tr ch. Bi vy dng thuc gii phng ti ch i trng l tng l bo v dc cht khng gii phng ti d dy, rut non, m bo dc cht gii phng hon ton ti i trng. iu ny i hi phi thit lp c c ch gii phng thch hp vi cc iu kin c th ca mi trng i trng. Thng thng t n ch i trng thng p dng bin php nhm gii phng thuc ng vo thi im thuc n i trng, dng polyme nhy cm pH, tin thuc hoc cc polyme b phn hy bi vi sinh vt i trng, trong bin php gii phng nh vi sinh vt l u vit hn cc phng php khc. Cc polymer c s dng pectin, gm xanthan, dextran, amylose, galactomanan. Bi v s c mt ca vi sinh vt i trng l c ch chnh cho s gii phng thuc nn test ha tan cn phi c thc hin ph hp iu kin sinh thi a dng ca i trng [8].

Mt s c im i trng lin quan dng thuc:

Vi sinh vt i trng: i trng ngi c khong 400 loi vi khun vi s lng 1011 1012CFU/ml. Mt s chng ch yu Bacteroides, Bifidobacterium, Eubacterium, Lactobacilus, Cc chng vi khun ny sn xut enzyme thy phn v enzyme kh ha nh glucosidase, gluconidase, -D fucosidase, -D galactosidase, nitroreductase, azoreductase, N- oxidase, sulfoxidase, Cc chng vi khun chu nh hng ca nhiu yu t nh ch n, bnh tt, tui, thuc.

Vn ng ti i trng: S vn ng ti i trng c nhiu c im khc bit so vi d dy v rut non do s khc bit ca tng vng v chc nng khc nhau.

59


Nc v in gii: i trng c kh nng hp thu ln: vi 2 lt nc vo i trng th c < 200 ml nc trong phn. Lu lng nh trp t rut non xung rut gi ngi khe mnh khong 12 lt/gi. S hp thu nc v Na+ khng ng k manh trng. S hp thu xy ra na u i trng [1].

pH: ngi, gi tr pH i trng khong 5,57,8. Trong pH i trng ln l 6,40,6; i trng ngang l 6,60,8 v i trng xung l 7,00,7. C nhiu yu t lm thay i pH cc phn i trng nh bnh tt, ch n, thuc [1].

1. M hnh th gii phng invitro da trn c s Tlag- pH

Hnh 1: c im pH v thi gian lu ti cc phn khc nhau ca ng tiu ha

M hnh thng p dng test th ha tan USP, chuyn lun vin bao tan trong rut c mt s ci tin. Ba mi trng thng c s dng: mi trng d dy, rut non, i trng tng ng pH d dy 1,2; 7,5 v 6,8. Thi gian ca mi giai on tng t thi gian lu gi thuc trong ng tiu ha: d dy 2h, rut non 3h.

u nhc im:

- Phng php n gin, d thc hin.

- Phng php ch da vo thang pH v thi gian nn tng i n nh.

- Phng php khng c hiu vi cc thuc gii phng ti i trng

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