PORTABLE)LABONADISC)SYSTEM)FOR)INSITU) AQUATIC ...doras.dcu.ie/17900/1/QUESTOR_-_Nov_2012_PDF_copy_2.pdf · • Intensity and efficiency • Low cost • Small size • Ease of

UNIVERSITY*COLLEGE*DUBLIN***!***DUBLIN*CITY*UNIVERSITY***!***TYNDALL*NATIONAL*INSTITUTE*

PORTABLE)LAB*ON*A*DISC)SYSTEM)FOR)IN*SITU)

AQUATIC)ENVIRONMENTAL)MONITORING)

1

Monika)Czugala

Prof.)Dermot)Diamond,)Dr.)Fernando)Benito*Lopez

MicroTAS)2012

http://www.qub.ac.uk/research-centres/ATWARM/














Presentation outline

2

• Introduction• Water quality analysis techniques

• Our challenge



2


• Our challenge

• Centrifugal Microfluidic Analysis System (CMAS)• Centrifugal platform design

• Photoswitchable valves

• CMAS performance



2


• Our challenge

• Centrifugal Microfluidic Analysis System (CMAS)• Centrifugal platform design



• Nitrite ions detection in water samples• Conclusions


Water quality analysis techniques

3

Traditionally

• Current norm: manual grab samples 3 or 4 times a year.

• Disadvantages: ✗ Low stability of natural water samples during long-term storage.[1] ✗ Expensive, time consuming and requires highly trained staff.

✓ portable✓ inexpencive

✗ single probe✗ no data saving

✓ multiprobe (temperature, pH, redox, DO, turbidity (TSS), NO3, Na, F, etc.) ✓ hand-held device

✗ €7000

[1] G. Hanraham, J. Environ. Monit. 6, 2004, 657.

In situ measurements

pH meterDO meter

Spectrophotometer

UNIVERSITY*COLLEGE*DUBLIN***!***DUBLIN*CITY*UNIVERSITY***!***TYNDALL*NATIONAL*INSTITUTE* 4

Our challenge

[2] Yole Development market report 2011


[4] J. Siegrist et. al., Lab Chip 10, 2010, 363.

.!

WHY CENTRIFUGAL DISC (CD)?

• Elimination of large power supplies and external pump[2].

• Provides forces across the entire length of a fluid element.

• Multiple individual micro-fluidic systems can be placed on a single CD.

• Potential to include multi-parameter assays and / or multiple replicate assays with calibration.

• Potential for multi-stage assays involving several fluidic sub-compartments.

Our challenge

[2]


!Colorimetric Analysis[2]

6

[2] M. Czugala, Lab Chip, 2012, DOI: 10.1039/C2LC40781G

Fluid Manipulation

Our challenge


0.2 mg/L

0.4 mg/L

0.6 mg/L

0.8 mg/L

1.0 mg/L1.2 mg/L

0.0 mg/L

Centrifugal Platform for Nitrite Detection

Assembly of the microfluidic CD Lab-on-a-Disc


Single chip consisting of three chambers.

Single Microfluidic Design

• Standard solution/Sample reservoir - 31.5 µL

• Air vent (bubble prevention)

• Griess Reagent reservoir - 2.1 µL

• Microchannels - 1000 µm width

• Mixing/Detection area - 33.5 µL

Dire

ctio

n of

flow

2 mm


Photoswitchable microvalves

Ionogel microvalve [2]

shrunk (left) and swollen (right) stateValve actuation at 600 rpm

[2] M. Czugala et. al., Proc SPIE. 8107, Nano-Opto-Mechanical Systems (NOMS), 2011.

4 mm

!

500 µm


Photoswitchable microvalves

Ionogel microvalve [2]

shrunk (left) and swollen (right) stateValve actuation at 600 rpm

[2] M. Czugala et. al., Proc SPIE. 8107, Nano-Opto-Mechanical Systems (NOMS), 2011.

4 mm

!

500 µm


Mechanism of the Nitrite Detection

10

!

[3] J. MacFaddin, 3rd ed. Lippincott Williams & Wilkins, Philadelphia, 2000, 348

sulfanilic acid (Reagent A)

diazonium salt

N-(1-naphthyl)ethylenediamine (Reagent B)

diazonium salt azo dye+

1.

2.

1.

2.

NO2-


Mechanism of the Colourimetric Detection

11

[4] M. O’Toole et. al., Anal. Chim. Acta, 652, 2009, 308.

Paired emitter detector diode (PEDD)



11

• Excellent sensitivity and signal-to-noise ratio [4]

• Low power consumption

• Increasing spectral range coverage

• Intensity and efficiency

• Low cost

• Small size

• Ease of fabrication

• Simplicity

• AND adjusts ideally to the system based on centrifugal Lab-on-a-disc!

[4] M. O’Toole et. al., Anal. Chim. Acta, 652, 2009, 308.

Paired emitter detector diode (PEDD)



12

!1

2

540 nm LED (emitter)

2

λmax = 537 nm


Centrifugal Microfluidic Analysis System (CMAS)

Patent Pending: Centrifugal Microfluidic Analysis System, K. J. Fraser, M. Czugala, D. Maher, F. Benito-Lopez, D. Diamond, 25 April, 2012, (GB)

Spinning + Colorimetric Analysis



Advantages:

• Low cost single use micro-fluidic device• Multiple samples analysis in a single microfluidic device• Multiplexing capabilities (pH, turbidity, nitrite,...)• Portable system: sample analysis at the point-of-need• Wireless communication system - including cloud integration!

Android Tablet

Batteries2 x 9V

CMAS system

CD Drive Motor500-4000 rpm

PEDD

Patent Pending: Centrifugal Microfluidic Analysis System, K. J. Fraser, M. Czugala, D. Maher, F. Benito-Lopez, D. Diamond, 25 April, 2012, (GB)



In collaboration with Prof. Smeaton’s group (School of Computing, DCU)

1%8%

18%

27%

45%

LED’s € 2.00 Batteries € 18.60 Misc Electronics € 40.00 Custom PCB Board € 59.94 Printed ABS case € 100.11

TOTAL: ~ €200Patent Pending: Centrifugal Microfluidic Analysis System, K. J. Fraser, M. Czugala, D. Maher, F. Benito-Lopez, D. Diamond, 25

April, 2012, (GB)


F. Detection

Nitrite)standard)soluNon

C. Valve opening

E. Alignment of CDD. Spinning of the CD

(600 rpm, 90 s)

B. Alignment of CDA. Loading the samples and reagent



Reproducibility tests

Detection of 0.2 mg/L NO2 Griess reagent complex (n = 10)

Reproducibility of the PEDD Reproducibility of the CDs

Detection of 0.2 mg/L NO2 Griess reagent complex (n = 6)

RSD = 0.36 % RSD = 0.26 %

46000

46500

47000

47500

48000

48500

49000

0 10 20 30 40 50 60 70

Dis

char

ge T

ime

[µs]

Time [s]


!Validation of the method - UV/Vis spectroscopy

Study of the colour formation between NO2 - and Griess reagent (left side) and absorbance versus nitrite Griess reagent complex concentration (right side) using a UV-Vis spectrometer.

0

0.5

1

1.5

2

2.5

0 5 10 15 20 25 30 35

Abs

orba

nce

[A.u

.]

Time [min]

1.2 mg

1.0 mg

0.8 mg

0.6 mg

0.4 mg

0.2 mg

L -1

L -1

L -1

L -1

L -1

L -1

y = 1.6458x + 0.0736 R² = 0.99

0

0.5

1

1.5

2

2.5

0 0.2 0.4 0.6 0.8 1 1.2 1.4 N

orm

alis

ed A

bsor

banc

e [A

.u.]

Concentration [mg L-1]

UV-Vistemp. 20 +/-0.5oC


Validation of the method - UV/Vis spectroscopy

0

0.5

1

1.5

2

2.5

0 5 10 15 20 25 30 35

Abs

orba

nce

[A.u

.]

Time [min]

1.2 mg

1.0 mg

0.8 mg

0.6 mg

0.4 mg

0.2 mg

L -1

L -1

L -1

L -1

L -1

L -1

y = 1.6458x + 0.0736 R² = 0.99

0

0.5

1

1.5

2

2.5

0 0.2 0.4 0.6 0.8 1 1.2 1.4

Nor

mal

ised

Abs

orba

nce

[A.u

.]

Concentration [mg L-1]

UV-Vistemp. 20 +/-0.5oC

0

2000

4000

6000

8000

10000

12000

14000

16000

18000

0 5 10 15 20 25 30 35

Nor

mal

ised

Dis

char

ge T

ime

[µs]

Time [min]

1.2 mg

1.0 mg

0.8 mg

0.6 mg

0.4 mg

0.2 mg

L -1

L -1

L -1

L -1

L -1

L -1

y = 12,898.46x - 248.19 R² = 0.99

0

2000

4000

6000

8000

10000

12000

14000

16000

18000

0 0.2 0.4 0.6 0.8 1 1.2 1.4

Nor

mal

ised

Dis

char

ge T

ime

[us]

Concentration [mg Λ } [mg L-1]

CMAStemp. 20 +/-0.5oC

Study of the colour formation between NO2 - and Griess reagent and absorbance versus nitrite Griess reagent complex concentration using spectrophotometer (up)

and the CMAS system (bottom).


Nitrate detection in real water samples

0

0.1

0.2

0.3

0.4

0.5

0.6

1 2 3 4 5

Nitr

ite C

once

ntra

tion

[mg/

L]

Sample number

UV-VIS

PEDD

[mg

L-1]

2

35

14

Water nitrite analysis using a bench-top UV-VIS spectrometer and the CMAS (n = 3)

CMAS


• A fully integrated, portable system for in-situ colorimetric water quality analysis has been developed.

• Integration of a wireless communication device allows data acquisition according to individual needs.

• We present the huge potential for the CMAS to be a cheap and versatile alternative as point-of-need optical detector for lab-on-a-disc applications.

Design

Functionality

• On site detection of nitrite with a LoD = 40 ppb.

• Cloud Integration / data management via Android tablet.

21 of 23

• Easily interchangeable PEDD boards allowing a wide range of centrifugal microfluidic layouts to be implemented.

Conclusions

• Successful application of photoswitchable microvalve on the centrifugal platform.


Acknowledgements

20

• Dr. Damien Maher• Dr. Robert Burger• Dr. Fiachra Collins• Thomas Phelan• Dr. Kevin J. Fraser• Prof. Jens Ducrée• Prof. Dermot Diamond• Dr. Fernando Benito-Lopez• Prof. Alan Smeaton’s group• Adaptive Sensors Group, Dublin City University• Marie Curie ITN funded by the EC FP7 People Program • Science Foundation of Ireland under grant 07/CE/I1147















Thank you for your attention!















• Centrifugal platform design


• Paired emitter detector diode (PEDD)

• Alignment of CD


• Reproducibility

• Validation of technique

• Water samples testing

Documents

PORTABLE)LAB*ON*A*DISC)SYSTEM)FOR)IN*SITU) AQUATIC ...doras.dcu.ie/17900/1/QUESTOR_-_Nov_2012_PDF_copy_2.pdf · • Intensity and efficiency • Low cost • Small size • Ease of

PORTABLE)LABONADISC)SYSTEM)FOR)INSITU) AQUATIC ...doras.dcu.ie/17900/1/QUESTOR_-_Nov_2012_PDF_copy_2.pdf · • Intensity and efficiency • Low cost • Small size • Ease of