polymer transistors and microfluidic devices for biosensor applications
TRANSCRIPT
Senaka Krishna Kanakamedala
Polymer based transistors & microfluidic devices for biosensor applications
Advisor : Dr. Mark A DeCoster
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Louisiana Tech University, Ruston, LA, USA
OECT : Low operating voltages , Aqueous environments & Simplified structure Electrode materials : Gold, silver and platinum Channel: Conducting polymersElectrolyte solution for electrochemical reactions
Introduction : Organic Electro Chemical Transistors (OECT)
Source (S)Drain (D)
Gate (G)
Electrolyte
Polymer channel2
OECT with Optimized Dimensions
3Fig: Schematic diagram of the OECT (top view)
Electrode & Channel material: PEDOT:PSS (conducting polymer)
OECT on Glass (left) & Polyester sheet (right)
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Fabricated Transistors
Film Thickness = 200 nm
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Surface roughness of the patterned film
Fig: AFM image of the PEDOT:PSS film
Transistors Characteristics
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Vds = Drain voltage, Ids = Drain current, and Vgs = Gate voltage
Glucose Sensor Response
I0 = Drain current before adding glucose
IC = Drain current after adding glucose (concentration of interest)
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Normalized Response
I0 - IC
I0 =
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Micromolar Glutamate Sensing
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Glutamate Release from Tumor Cells
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Developed Field Effect Transistors
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4.5 mm
4.6 mm
Two sensor devices on a single chip
Gold electrodes are separated by a narrow channel
Channel length = 50µm
Flexible disposable micromixer
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Inlet 1Inlet 2
Outlet
Fig : Solid works model of the polymer micromixer (left), three layered polymer patterns constitute microchannel of the micromixer (right)
Fabricated flexible microfluidic devices
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