MEMS design and Micro-fabrication LabMML

SU-8 Mold PDMS replication

MIP Reactor

Micropump

Microvalve

(a) (b)

(c) (d)

Heater

Temp. Sensor

(e)

200µm50µm

2-Dimensional SPR Detection System Integrated with Molecular 2-Dimensional SPR Detection System Integrated with Molecular Imprinting Polymer Microarrays Using Microfluidic TechnologyImprinting Polymer Microarrays Using Microfluidic Technology

Kuo-Hoong LeeKuo-Hoong Lee, Yuan-Deng Su, Shean-Jen Chen and Gwo-Bin Lee, Yuan-Deng Su, Shean-Jen Chen and Gwo-Bin LeeDepartment of Engineering Science, National Cheng Kung University, Tainan, Taiwan 701Department of Engineering Science, National Cheng Kung University, Tainan, Taiwan 701

This study reports a novel microfluidic chip integrated with arrayed molecular imprinting polymer (MIP) films for surface plasmon resonance (SPR) phase imaging of specific bio-samples. The SPR imaging system uses a surface-sensitive optical technique to detect two-dimensional spatial phase variation caused by bio-molecules absorbed on a sensing surface composed of highly-specific MIP films. The developed system has a high resolution and a high-throughput screening capability and has been successfully applied to the analysis of multiple bio-molecules without the need for additional labeling in long-term measuring.

Simplified fabrication process of the SPR/MIP microfluidic chip. (a) SU-8 molding and PDMS casting fabrication process; (b) Spin-coating of MIP films and polymerization process; (c) Temperature sensor and heaters fabricated by using lift-off technique.

A novel SPR/MIP microfluidic chip integrated with arrayed MIP films for SPR phase imaging of specific bio-samples was developed.Multiple MIP films could be used for highly-sensitive, highly-specific bio-sensing.The development of the SPR/MIP microfluidic chip can be promising for nano-sensing applications and can detect bio-samples with a low molecular weight.

The temperature control system can heated up bio-samples to 37 °C within 20s and kept them

at a uniform temperature.

A SPR/MIP microfluidic chip comprising microchannels, micropumps/microvalves, micro-heaters and temperature sensors coupled with a 2-D SPR imaging system was developed. Micropumps were used to automate the sample injection. A micromachine-based temperature control module comprised of micro-heaters and a temperature sensor was used to maintain the temperature during measurement.

0 50 100 1500

0.002

0.004

0.006

0.008

0.01

Time (min)

SPR

angl

e sh

ift (d

eg)

Flowed progesterone sample

Arrived saturation

Washed with ethanol

0 50 100 1500

0.002

0.004

0.006

0.008

0.01

Time (min)

SPR

angl

e sh

ift (d

eg)

Flowed progesterone sample

Arrived saturation

Washed with ethanol

The detection kinetics of 50 μM progesterone. Reaction procedure (0 ~ 21 min : ethanol, 21 ~ 126 min : ethanol + 50μM progesterone, 126 min ~ : ethanol).

(a) SPR phase interference image and (b) phase reconstructed image when ethanol flows through the arrayed MIP films.

The relationship between the pumping rate and the driving frequency.

prism

Slide(SF-11)Au (47.5 nm)

Glass

OutletInlet

θ 1

CCDHe-Ne laser

Micropump

Microchannel

Arrayed MIPHeater

Temp. Sensor

prism

Slide(SF-11)Au (47.5 nm)

Glass

OutletInlet

θ 1

CCDHe-Ne laser

Micropump

Microchannel

Arrayed MIPHeater

Temp. Sensor

SU-8 molding

PDMS replication

Si

PDMS bonding

Cleaning

PDMS release / Via hole formation

Sputtering 47.5nm Au

Thiol group modification

MIP spin coating and polymerization

Slide

Lithography

Pt deposition

PR lift-off

Au lead deposition

Glass

Assembly

(a)

(b)

(c)

SU-8 molding

PDMS replication

Si

PDMS bonding

Cleaning

PDMS release / Via hole formation

Sputtering 47.5nm Au

Thiol group modification

MIP spin coating and polymerization

SlideSlide

Lithography

Pt deposition

PR lift-off

Au lead deposition

Glass

AssemblyAssembly

(a)

(b)

(c)

6 cm

Heater

Temp.Sensor

4 cm

Glass

MicropumpMicrovalve

PDMS layer1 & layer2 PDMS layer3

Microchannel

Arrayed MIP films

Inlet Outlet

6 cm

Heater

Temp.Sensor

4 cm

Glass

MicropumpMicrovalve

PDMS layer1 & layer2 PDMS layer3

Microchannel

Arrayed MIP films

Inlet Outlet

MicrochannelMicropump/valve

Inlet Outlet

PDMS #2

PDMS #3

PDMS #1Heater

Slide (SF-11)

Sensor

MicrochannelMicropump/valve

Inlet Outlet

PDMS #2

PDMS #3

PDMS #1

Heater

Slide (SF 11)-

Temp. sensor

Gold film

MicrochannelMicropump/valve

Inlet Outlet

PDMS #2

PDMS #3

PDMS #1Heater

Slide (SF-11)

Sensor

MicrochannelMicropump/valve

Inlet Outlet

PDMS #2

PDMS #3

PDMS #1

Heater

Slide (SF 11)-

Temp. sensor

Gold film

(a) Schematic illustration of the arrayed SPR/MIP microfluidic chip (b) Cross-sectional view showing that three layers of PDMS could be used to transport samples from inlet to outlet through the arrayed MIP films.

Freq. (Hz)

Pum

ping

rate

(ul/m

in)

0 5 10 15 20

10

20

30

40

50

25 psi20 psi15 psi10 psi

Time (s)

Tem

pera

ture

(o C)

0 25 50 75 10025

30

35

40

45

SEM images of the SU-8 molds (a and c) and PDMS replicas (b and d) of the arrayed MIP reactors and micropumps/valves. (e) the temperature sensor and heater.

Design

Conclusions

Results

Fabrication

Abstract

The authors gratefully acknowledge the financial support provided to this study by the MOE Program for Promoting Academic Excellence of Universities (Grant number EX- A-91-E-FA08-1-4).

Acknowledgements

(a) (b)

(a)

(b)

2006