Development of a Modular Peristaltic Microfluidic Pump and Valve System

3/13/2007

BME 273 Group 20:

Adam Dyess, Jake Hughey, Michael Moustoukas, Matt Pfister

2

Microfluidics for Biology

Reduced reagent consumption Precise control of microenvironment Study of biological phenomena at the single

cell level

3

Microfluidics at VIIBRE

Immunology T cell signaling & activation,

proliferation, and cycling Chemotaxis

Traction force & cell migration Cell Forces

Traction force bed of nails & cell to cell adhesion

Haptotaxis Rapid generation of protein gradients

on a substrate Cancer

Angiogenesis & Metastasis bioreactors

Biodefense Metabolic dynamics for toxic

discrimination

Ionomycin-induced Ca++ cycling in T cells

CRAC Channel Oscillations

90

100

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Time 10 20 30 40 50 60 70 80 90 100 110 120

Time (min)

Flu

ore

sc

en

ce

Inte

ns

ity

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Current Pumps at VIIBRE

Harvard Pico Plus syringe pumps

$2,000 / pump Difficult to avoid bubbles Limiting complexity of

microfluidic devices

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Ideal On-chip Pumping System

Switch flow rates from a minimum of 50 nl/min to a maximum of 300 nl/min with an accuracy of 10 nl/min

Rotate between 4 different solutions in milliseconds with no leakage

Minimize cost of materials (<$200)

Immediate needs Flow recirculation Some experiments require a complete fluidic circuit on-chip

Long-term Point of care device

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Pressure

Vacuum

Parallel Port Connection

Nanophysiometer

Cell Loader

Polyphase Pump Trapped Cells

Via

Basic Schematic

Microfluidic Device

Input Channels

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Pneumatic Valves

Two-layer PDMS device Flow layer Control layer

Thin PDMS membrane deflects into the flow channel when the control channel is pressurized

Unger et al. 2000

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Polyphase Pump

Each pump has four valves in series Flow channel

100 µm wide, 10 µm tall (round) Control channel

25 µm tall, valve area is 300 µm by 300 µm

Four pumps in parallel Increase flow rate Reduce flow rate oscillations Air compressor provides vacuum in

the off state

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Flow Channel Below (1→4)

Control

Flow

0

50

100

150

200

250

300

0 0.05 0.1 0.15 0.2 0.25 0.3 0.35

1 / Pump Period

Q (

nl/

min

)

Flow rates measured by bubble displacement in output tubing

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Flow Channel Above (1→4→1)

Control

Flow

0

50

100

150

200

250

300

350

400

450

500

0 0.2 0.4 0.6 0.8 1 1.2

1 / Pump Period

Q (

nL

/min

)

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Latest Version of Polyphase Pump

Multiple fluid inputs Valves to selectively block

individual lanes Flow rate tester 100 µm or 200 µm wide

flow channels Calls for controller box

with at least 9 inputs Requires extension of

LabVIEW program

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12 Valve Controller1

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Opto1

1

2

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4

5

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8 9

10

11

12

13

14

15

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Opto3

12345678

16

15

14

13

12

11

10

9

R1Res Pack3

12345678

16

15

14

13

12

11

10

9

R2Res Pack3

12345678

161514131211109

R3

Res Pack3

1 2 3 4 5 6 7 8

16

15

14

13

12

11

10

9

R4Res Pack3

12345678

161514131211109

R5

Res Pack3

12345678

16

15

14

13

12

11

10

9

R6Res Pack3

120

221

322

423

524

625

78910

11

12

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27

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J1D Connector 25

1

2

JP1

1

2

JP2

1

2

JP3

1

2

JP4

1

2

JP5

1

2

JP6

1

2

JP7

1

2

JP8

1

2

JP9

1

2

JP10

1

2

JP11

1

2

JP12

T2BCX56

T4BCX56

T7BCX56

T6BCX56

T5BCX56

T8BCX56

T9BCX56

T3BCX56

T10BCX56

T11BCX56

T12BCX56

T1BCX56

D1RS1A

D2RS1A

D3RS1A

D4RS1A

D5RS1A

D6RS1A

D7RS1A

D8RS1A

D9RS1A

D10RS1A

D11RS1A

D12RS1A

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P1

Header 2

VCCVCC

VCC VCC

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8 9

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Opto2

LED 1A

LED 1B

LED 1C

LED 1D

LED 1E

LED 1F

LED 1G

LED 1H

LED 1I

LED 1J

LED 1K

LED 1L

Schematic Using Altium DesignerParallel Port

Optocoupler

Resistors

TransistorsDiodes

2-pin Header

Amplifier

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12 Valve Controller

Printed Circuit Board

Vendor: Advanced Circuits

Cost: $40/PCB

Arrival: Friday

Circuit Components

Parts: 47 + Box + tubing

Cost: ~$100 / controller

Arrival: Friday

PCB designed in Protel

4.5”

2.312”

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LabVIEW Interface

Integrate Excel spreadsheet into LabView controls

Spreadsheet controls valves (on/off), duration of trial, repetition

NI clock to guarantee timing Empirically correlate pump speed

with actuation frequency

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Current Work

Optimize fabrication procedures for new pump design Y junctions and steel needles for easier pump assembly Fabrication of microfluidic vias Measure flow rate vs. outlet pressure head Characterize flow oscillations

Pulse-chase with bolus of fluorescent solution Head to head vs. syringe pump

Groisman & Quake 2004

t = 0

t = d / v

Kartalov et al. 2006

Flow

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Future Work

Investigate influence of downstream resistance

Effect of membrane thickness on performance and durability of pumps

Increase aspect ratio of flow channels

Incorporate gradient device or T cell device on chip with pump

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20

25

30

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40

45

50

55

1000 1200 1400 1600 1800 2000 2200 2400 2600

Speed (rpm)

Th

ick

ne

ss

(u

m)

20:1

10:1

PDMS Film Thickness

PDMS thickness measured using displacement gauge