localized and automated chemical and oxygen delivery system for microfluidic brain slice devices
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Localized and automated chemical and oxygen delivery system for microfluidic brain slice devices. Author: Gene Yu Co-Authors: Dr. AlexBlake Dr. David Eddington July 29, 2010 NSF Research Experiences for Undergraduates (REU) in - PowerPoint PPT PresentationTRANSCRIPT
Localized and automated chemical and oxygen delivery system for microfluidic brain slice devices
Author: Gene Yu Co-Authors: Dr. AlexBlake
Dr. David EddingtonJuly 29, 2010
NSF Research Experiences for Undergraduates (REU) inNovel Advanced Materials and Processing with Applications in Biomedical, Electrical and
Chemical Engineering
ObjectiveDesign localized and
automated delivery system for microfluidic brain slice devices (μBSDs)
Delivers chemicals/drugs and gases
Automatically mixes oxygen
Characterize delivery of chemicals through tissue Image taken from
Mohammed, J, Caicedo, H, Fall, C, & Eddington, D. (2008). Microfluidic add-on for standard electrophysiology chambers. Lab Chip, 8, 1048-1055.
MotivationμBSDs allow in vitro study of:
NeurogenesisSynaptogenesisRegenerationProtein expressionResponses to physical trauma
Image taken fromhttp://www.koki.hu/cdnb/research/research.html
Rambani, K, Vukasinovic, J, Glezer, A, & Potter, S. (2009). Culturing thick brain slices: an interstitial 3d microperfusion system for enhanced viability. Journal of Neuroscience Methods, 180, 243-254.
RelevanceChemical Delivery
Spatial resolution Current systems affect entire
slice with drug Desire stimulation of specific
areasOxygen Delivery
Automatic Mixing Saves money Pre-mixing is not required
AutomationMulti-tasking
Image modified fromhttp://www.imagingeconomics.com/issues/articles/MI_2006-08_01.asp
Oxygen Mixing and DeliveryExperimental Set-Up
Y Connector
Output Tube
Valves Gas Feed Lines: 0% and 21%
Oxygen concentration measured by a NeoFox Fiber Optic Oxygen (FOXY) sensor
Oxygen Mixing and DeliveryOutput
1 2 3 4 5 6 7 8 9 10 11 12 13 14 15 16 17 18 19 20 210
4
8
12
16
20
Oxygen Output
Desired Oxygen Levels (%)
Ave
rage
Exp
eri-
men
tal O
xyge
n Le
v-el
s (%
)
Oxygen Mixing and DeliveryGraphical User Interface (GUI)
Delivery CharacterizationμBSD Design
T Channel
Delivery Channel
Reservoir
Delivery CharacterizationExperimental Set-up
μBSD
Valve
DI Water Lines T Channel
Vacuum Line
Delivery CharacterizationNo Tissue Delivery
10ms 15ms 20ms 25ms
2x5ms 3x5ms 4x5ms 5x5ms
Delivery CharacterizationLinear Relationships: No Tissue
Width (µm)
Width (µm)
860
1320
Delivery CharacterizationLinear Relationships: With Tissue
Full Dose Chemical Delivery
Pulsing Dose Chemical Delivery
0 0.5 1 1.5 2 2.5 3 3.5 4 4.50
20406080
100120140160
f(x) = 19.750471 x + 1.3889974R² = 0.97197294218466
Maximum Intensities
0 2 4 6Number of 5ms Pulses
Inte
nsity
Inte
nsity
Inte
nsity
Time (min)
Time (min)
2
2
0 5 10 15 20 25 300
20406080
100120140
f(x) = 4.904786 x + 12.66823R² = 0.898041669777912
Maximum Intensities
0 10 20
30Valve Open Time (ms)
Inte
nsity
Delivery CharacterizationGUI
ConclusionsOxygen Delivery
Precise and accurate results
Reliable oxygen switching
Chemical Delivery Demonstrated linear
relationship Area of effect: ~2mm x
2mm Selective and
independent valve control
AcknowledgementsFunding
NSF-REU DoD-ASSURE EEC-NSF Grant # 0755115
REU Directors Christos G. Takoudis, Ph.D. Greg Jursich, Ph.D.
Research Advisor David Thomas Eddington, Ph.D.
Mentors Alexander Blake, Ph.D. Gerardo Mauleon