Slide 2 How to get an A and grasp this concept! Know the
differences between osmosis and diffusion Know page 171 in your
calculations book, backwards and forward Instead of plugging and
chugging actually understand where the equations come from and what
they are giving you Understand why this concept is important. You
WILL see it again in other classes whether you realize it or not
(i.e. major drug classes revolve around this concept, such as
diuretics) Slide 3 How to get an A and grasp this concept!
Understand the difference between hypertonic, hypotonic, and
isotonic and how it affects cells Remember to double check your
work. An eraser costs 10 cents, a mistake can cost you millions and
your pharmacy license! Slide 4 Basic Concept: Osmosis and Diffusion
Slide 5 Osmosis is the passage of WATER from an area of high
concentration to an area of low concentration through a partially
permeable membrane Diffusion is the passage of molecules from an
area of high concentration to an area of lower concentration Slide
6 Basic Concept: Osmosis and Diffusion In the previous example,
osmosis occurs because the membrane is NOT PERMEABLE to the sugar
molecules but is permeable to the water. If there was a completely
permeable membrane, the water would move to the left and the sugar
molecules would move to the right until EQUAL concentrations of
each were on both sides Slide 7 Basic Concept: Osmotic Pressure The
pressure required to prevent solvent from passing through a
semipermeable membrane from a region of higher concentration of
solute to a region of lower concentration of solute. Slide 8
Osmosis and Diffusion: Application to real life What does all this
have to do with pharmacy? Believe it or not, all cells are
semi-permeable Thus, they allow some stuff to pass while inhibiting
others from passing This occurs through various processes, such as
active diffusion, passive diffusion, etc. The concept we need to
understand is that cells will behave differently based on what
solution they are in because water can move by way of osmosis Slide
9 Osmosis and Diffusion: Application to real life Say we have a
human cell that contains 10% (THIS IS A CONCENTRATION) NaCl within
its cell membrane. There are basically 3 different solutions we can
place it in There are solutions that are more concentrated There
are solutions that are less concentrated There are solutions that
are the same concentration Slide 10 Osmosis and Diffusion:
Application to real life If we placed the cell in the previous
slide in a solution that contains the same concentration of NaCl
then there would be no net movement of water because the cell is at
equlibrium When this occurs, the solution is said to be isotonic
Note that even though there is no net movement of water, water
still goes back and forth Slide 11 Osmosis and Diffusion:
Application to real life What would happen if we placed a cell with
20% NaCl in a solution that only had 10% NaCl? Slide 12 Osmosis and
Diffusion: Application to real life In this situation, the cell is
MORE CONCENTRATED with solute particles than the solution (i.e. the
outside of the cell has more WATER per unit volume) Remember, water
moves from an area of high concentration to low concentration Thus,
water will move into the cell This type of solution is called
Hypotonic Slide 13 Osmosis and Diffusion: Application to real life
What if the solution contained a higher concentration of solute
(NaCl)? Slide 14 Application to life: One step further Instead of a
regular cell, lets see what would happen with a red blood cell!
Slide 15 Application to life: One step further When a red blood
cell is placed in an isotonic solution nothing happens When a red
blood cell is placed is a hypertonic solution the cell begins to
shrink as water goes out of the cell, a process called CRENATION
When a red blood cell is placed in a hypotonic solution the cell
begins to swell and burst, a process called lysis (hemolysis) Slide
16 One more step further Knowing what you know now, explain what
would happen in the following situations Applying 5% NaCl eyedrops
to the eye given that the concentration of the eye is 0.9%
Commercially available as Muro 128 eyedrops Swallowing mannitol
which is a nonelectrolyte that behaves like NaCl and is impermeable
to the intestines Hold your pee for a Wii!!! Slide 17 Important
Note Remember, osmotic pressure that is produced on either side of
a membrane is related to the number of particles the solute
produces, not just the concentration. i.e. A cell placed in a 10%
solution of KCl will behave differently than a cell placed is a
solution of 10% NaCl because of Osmolarity of the different
molecules Explained in detail later Slide 18 Basic Concept:
Electrolyte vs. Nonelectrolyte An electrolyte is a molecule that
dissociates into solution and conducts current due to a charge on
the molecule Examples include NaCl, KCl, etc. When an electrolyte
is placed in a solution, it produces 1 Osmol for every particle
that dissociates (assuming 1 molecular weight) NaCl Example A
nonelectrolyte doesnt dissociate when placed in solution Examples
include Dextrose, Boric Acid, Mannitol When an electrolyte is
placed in a solution, it only produces 1 Osmol (assuming 1
molecular weight) Dextrose Example Slide 19 Basic Concept:
Molecular weight and other measures The molecular weight and the
"electrolyte status of a molecule gives us a bunch of information
Know that 1 Osmol is the amount of a solute that will provide 1
Avagadros Number of particles Based on this information, we can
deduce that if we have a solution of 1 molar dextrose and 1 molar
NaCl that the NaCl solution would have more particles because it
gives 2 Osmol per mole Slide 20 Understanding the differences
between substances Suppose in the below diagram we had 58.5 g (1
mole) of NaCl on the left side of the semi-permeable membrane and
on the right side we had 61.8 g (1 mole) of Boric acid Which way
would the water move? Why? Slide 21 Understanding the differences
between substances With only knowing the fact that NaCl is an
electrolyte and Boric Acid is a nonelectrolyte and that we have 1
molecular weight of each we can tell that the NaCl side would have
more particles Thus, water would move into the NaCl compartment
Slide 22 Understanding the differences between substances Suppose
in the below diagram we had 10% NaCl on the left side and 10% KCl
on the right side (assume equal volume of solution on each side)
Which way would the water move? Slide 23 Understanding the
differences between substances In the example, we have to take into
consideration the molecular weights and Osmolarity of the two
substances. The MW of NaCl is 58.5 g which provides 2 Osmol, thus
in a 10% solution we would only have 0.1709 moles or 0.3418 Osmol
The MW of KCl is 75 g which provides 2 Osmol, thus in a 10%
solution we would only have 0.1333 moles or 0.2666 Osmol Based on
this we can see that there would be more particles on the NaCl side
and thus water would move into the NaCl compartment Slide 24
Understanding the differences between substances Suppose we had 0.1
molar solutions of two different nonelectrolytes, say dextrose and
boric acid, in the below diagram Which way would water move? Slide
25 Understanding the differences between substances Because there
are an equal number of moles of two nonelectrolytes, and thus the
same number of particles, the net movement of water will be zero!
Slide 26 Homework! Look up NORMALITY and know how it would come
into play in the above scenarios (i.e. 1N NaCl on one side and 1N
KCl on one side) Slide 27 A side note on particle number How many
Osmol would 1 mole of CaCl2 provide in solution? Slide 28 Whats the
purpose of all this? The whole idea is to be able to make a
solution that will either be isotonic, hypertonic, or hypotonic
with body fluids in order to get the effects we want. For example,
if we want to give someone fluid to prevent dehydration we want it
to be isotonic with the blood so we wont hurt the red blood cells.
Or if we want to make someone have a bowel movement we want to make
the inside of the intestines Hypertonic so water will come into the
intestines and produce a bowel movement Slide 29 Colligative
properties Colligative properties are properties of solutions that
depend on the number of molecules in a given volume of solvent and
not on the properties (e.g. size or mass) of the molecules There
are 4 colligative properties: Boiling point, Freezing point, Vapor
Pressure, and Osmotic Pressure To understand how each of these
behave, lets talk about salt. Slide 30 Colligative properties
continued Thus, when we add salt to a pot of water 4 things happen:
The vapor pressure goes down The osmotic pressure goes up The
boiling points goes up The freezing point goes down To help you
remember this, just keep in mind: Slide 31 Colligative properties
continued Of the properties, we will be using the freezing point
for class purposes When you add exactly 1 mole of a nonelectrolyte
to water it brings the freezing point down to -1.86 degrees celcius
What do you think would happen if we added 1 mole of an
electrolyte? Would it bring it down even further (depress it) or
raise it further? Slide 32 Colligative properties continued If we
add an electrolyte, it will depress it even further depending on
how much the molecule dissociates in solution (i.e. creates more
particles) This brings us to the concept of the i value Is a
proportionality constant that relates number of particles to
freezing point depression We determine this value based on the
assumption that electrolytes, with a few exceptions, dissociate at
80% in solution Slide 33 Colligative properties continued How to
calculate NaCl Value How to calculate KCl Value How to calculate
CaCl2 value Exceptions (Zinc Sulfate) Slide 34 The bodys freezing
point Based on the concentration of different solutes in our blood
and bodily fluids, it has been found that we will freeze at -0.52
degrees Celsius Walt-Disney! If we know that a 1 molar solution of
NaCl freezes at 1.8 * -1.86 degrees Celsius then we can determine
what molar solution of NaCl freezes at -0.52 degrees Celsius Thus,
it will be isotonic with body fluids Slide 35 Equation number 1!
Mole in gL -1.= - 1.86 o C*i XgL -1. - 0.52 o C Slide 36 Standard
Calculations Now we are able to calculate what percent solution of
different solutes are isotonic with bodily fluids NaCl Dextrose
Boric Acid KNO3 Slide 37 Standard Calculations Note: There is a
difference between something that is isotonic and isoosmotic!
Isoosmotic => Same number of Osmoles Isotonic=> Physiological
compatability Slide 38 Standard Calculations Slide 39 True or
False: Everything that is isotonic is isoosmotic. True or False:
Everything that is isoosmotic is isotonic. Slide 40 Methods for
making something isotonic There are three different ways to
calculate how to make something isotonic The D Method, or
depression method The E Method, or equivalent method The V Method,
or volume method Slide 41 The D Method Youre working in a
compounding pharmacy when you receive the following prescription
from Dr. Saber Samaan: Rx Naphazoline HCl0.02% [ 247,2] Zinc
sulfate0.25% Purified waterqs 30 mL Mft Isotonic solution Slide 42
Freezing Point Depression Explaination With the D method, you are
seeing how much each drug required of the prescription depresses
the freezing point towards -0.52 degrees celsius. You will then
make up the difference with NaCl or whatever other agent the
prescription calls for to make it isotonic! Slide 43 Freezing Point
Depression The first step is to calculate how much NaCl would be
needed to make the volume of the prescription isotonic! Its a
simple proportion from the 0.9% reference we already know If 0.9
grams will make 100 mL isotonic, how many grams will make 30 mL
isotonic? Slide 44 FREEZING POINT D EPRESSION 247gL -1 = - 1.86 o
C*1.8 0.2gL -1 - X o C Naphazoline HCl - 0.0027 o C Slide 45
FREEZING POINT D EPRESSION 288gL -1 = - 1.86 o C*1.4 2.5gL -1 - X o
C ZnSO 4 0.0226 o C Slide 46 Total depression 0.0027 o C + 0.0226 o
C 0.0253 o C Slide 47 = -0.52-(-0.0253) = 0.4947 o C Slide 48 270
mg0.52 o C Xmg0.4947 o C Slide 49 The Equivalent Method The E
method is a littler different Here, we are basically seeing how
much NaCl produces the same osmotic effect as 1 gram of the drug!
In essence, we are converting the drugs in the prescription to its
NaCl equivalent In order to do so we have to take into account the
drugs i value and molecular weight Slide 50 The Equivalent Method
The first step here is the same as the first step in the D method
Slide 51 The Equivalent Method Mole of NaCl gL -1 * i Drug Mole of
drug gL -1 * i NaCl Slide 52 247gL -1 *1.8 58.5gL -1 *1.8 = 0.2368
g NaCl The Equivalent Method Slide 53 Knowing this, we must now set
up a proportion If 1 gram of Naphazoline HCl is equal to 0.2368
grams of NaCl, then 0.006 grams of Naphazoline is equal to X grams
of NaCl? Slide 54 288gL -1 *1.8 58.5gL -1 *1.4 = 0.1579 The
Equivalent Method Slide 55 Knowing this, we must now set up a
proportion If 1 gram of Zinc Sulfate is equal to 0.1579 grams of
NaCl, then 0.075 grams is equal to X grams of NaCl? Slide 56 The
Equivalent Method The next step is to sum up the two quantities
calculated and subtract them from step 1! Slide 57 The Volume
Method The V method relies on the E value and involves a lot of
proportions The purpose of this method is to determine how much
water the drug should be dissolved in and then the excess volume of
the prescription is made up with NSS Slide 58 247gL -1 *1.8 58.5gL
-1 *1.8 = 0.2368 g NaCl The Volume Method Slide 59 100 mL0.9gNaCl x
mL 0.2368 gNaCl x mL = 26.32mL Dissolving 1 g of Naph.HCl in 26.32
mL of distilled water, the solution will be isotonic. Slide 60
26.32mL1 g N.HCl x mL0.006 gN.HCl 0.15792 mL If you dissolve 6 mg
of N.HCl in 0.16 of water, the sol. will be isotonic. Slide 61
288gL -1 *1.8 58.5gL -1 *1.4 = 0.1579 The Volume Method Slide 62
100 mL0.9gNaCl x mL 0.1579 gNaCl 0.1579 gNaCl x mL = 17.5mL
Dissolving 1 g of ZnSO 4 in 17.5 mL of distilled water, the
solution will be isotonic. Slide 63 17.5mL1 g ZnSO 4 x mL0.075 g
ZnSO4 1.31 mL 1.31 mL If you dissolve 75 mg of ZnSO 4 in 1.31 mL of
H 2 O, the sol. will be isotonic. Slide 64 1.3125 mL 0.1579 mL
1.4704mL Slide 65 Dissolve 6 mg of naph.HCl & 75 mg ZnSO 4 in
1.47 mL water, and qs to 30 mL with isotonic 0.9% NaCl. Slide 66
*This is the easy part* Slide 67 Electryoltes Na & Cl are the
most plentiful electrolytes in the body NORMAL HEALTHY HUMAN:
NORMAL HEALTHY HUMAN: Na 138-146 mMol.L -1 Na 138-146 mMol.L -1 Cl
98-109 mMol.L -1 Cl 98-109 mMol.L -1 K 3.7-5.3 mMol.L -1 K 3.7-5.3
mMol.L -1 Ca 2.25-2.65 mMol.L -1 Ca 2.25-2.65 mMol.L -1 *Memorize
this table, it will prove useful on the test and in other classes
to come! Slide 68 Osmoticity: Application to real life Believe it
or not, the simplest things in life all relate to everything weve
been talking about Why do we become thirsty? Slide 69 Signs and
Symptoms of Osmoticity Changes Normal 285 mOsmol kg -1 282-288
mOsmol kg -1 THIRSTY 294-298 mOsmol kg -1 DRY MUCOUS
MEMBRANE:299-313 mOsmol kg -1 WEAKNESS, DOUGHY SKIN: 314-329 mOsmol
kg -1 Once your plasma osmoticity >330 mOsmol/kg: Disorientation
Orthasis Severe Weakness Fainting Coma Slide 70 Signs and Symptoms
of Osmoticity Changes As your Osmoticity goes below normal range:
Headache (275-261) Drowsiness (262-251) Cramps (250-233) Seizures
& Coma (
