Droplet Gradient Array For Parallel Experimentation via Microfluidic Device

Droplet Gradient Array For Parallel Experimentation via Microfluidic Device

Lindsay PickettFaculty Mentor: Abraham P. Lee

Graduate Mentor: Rob LinIM-SURE 2006

Lindsay PickettFaculty Mentor: Abraham P. Lee

Graduate Mentor: Rob LinIM-SURE 2006

Outline of DiscussionOutline of Discussion

IntroductionGoals

ProcessResultsIssues

SolutionsFuture Direction

IntroductionGoals

ProcessResultsIssues

SolutionsFuture Direction

IntroductionMicrofluidic Devices

IntroductionMicrofluidic Devices

• Widely applicable- engineering, biology, chemistry– Research tools– Commercial applications

• Advantages: – microscale fluid physics– less reagent & shorter Rxn time – parallel operations – lab space conservation,– easy/cheap fabrication

• Widely applicable- engineering, biology, chemistry– Research tools– Commercial applications

• Advantages: – microscale fluid physics– less reagent & shorter Rxn time – parallel operations – lab space conservation,– easy/cheap fabrication

Project GoalProject Goal

Droplet Gradient Array

Ismagilov Laboratory– Thorough characterization– Control over droplet properties

• Droplet volume•Gradient steps

– Versatility of device for multiple applications

Droplet Gradient Array

Ismagilov Laboratory– Thorough characterization– Control over droplet properties

• Droplet volume•Gradient steps

– Versatility of device for multiple applications

Project OutlineProject Outline

Process: Device designFabrication TestingExternal valve

systemComputer-

mediated step gradient

Characterization

Process: Device designFabrication TestingExternal valve

systemComputer-

mediated step gradient

Characterization

QuickTime™ and a decompressor

are needed to see this picture.

Device DesignDevice Design

Outlet reservoir

Reagent Inlets

Oil Inlet

Shearing JunctionArray Observation Region

Process: Device designProcess: Device design

12 µm

7.5 µm

70/30 µm 50/50 µm 12/7.5 µm12/7.5 µm

Process: Experimental SetupProcess: Experimental Setup

Results:Testing

Results:Testing

• Top Aq. Inlet: DI (variable rate)

• Bottom Aq. Inlet: DI + dye (const. rate)

• Oil inlet: Silicon oil (const. rate 2µL/min)

*Droplet content control*

• Top Aq. Inlet: DI (variable rate)

• Bottom Aq. Inlet: DI + dye (const. rate)

• Oil inlet: Silicon oil (const. rate 2µL/min)

*Droplet content control*

0.80 vs 0.70 µL/min

0.95 vs 0.70 µL/min

1.25 vs 0.70 µL/min

QuickTime™ and a decompressor

are needed to see this picture.

Results: Array Capture (Colorcam)

Results: Array Capture (Colorcam)

• Array image capture external valves work• Not pictured instability introduced by valves

– Initializing system: backflow, fluctuation of flow rate– Over 20 min observation period: chaotic, random instability

• Array image capture external valves work• Not pictured instability introduced by valves

– Initializing system: backflow, fluctuation of flow rate– Over 20 min observation period: chaotic, random instability

Solutions…Solutions…

VALVES• Contacted vendor…

– no suitable suggestions

– different fluid route (Dr. Lee)

• Different External Valves• Quake pressure-

actuation Valves• 2-D valve for sufficient

freeze

VALVES• Contacted vendor…

– no suitable suggestions

– different fluid route (Dr. Lee)

• Different External Valves• Quake pressure-

actuation Valves• 2-D valve for sufficient

freeze

QuickTime™ and aTIFF (Uncompressed) decompressor

are needed to see this picture.

QuickTime™ and aTIFF (Uncompressed) decompressor

are needed to see this picture.

Other Solutions…Other Solutions…

*Fluid re-routing…*new filtration design… *input tips*Fluid re-routing…*new filtration design… *input tips

Future DirectionFuture Direction

• Valves/new designs• Computer-mediated

step gradient (Hyperterminal)

• Characterization via GFP and ImageJStep gradientDroplet volume

• Valves/new designs• Computer-mediated

step gradient (Hyperterminal)

• Characterization via GFP and ImageJStep gradientDroplet volume

AcknowledgementsAcknowledgements

• NSF and the IMSURE program• Abraham P. Lee (faculty mentor)• Rob Lin (grad. student mentor)• Lee laboratory team• Eckerd College Biochemistry Dept.

• NSF and the IMSURE program• Abraham P. Lee (faculty mentor)• Rob Lin (grad. student mentor)• Lee laboratory team• Eckerd College Biochemistry Dept.