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Biotechnology – Biochip Model Provided by Dr. MacInnes Sheffield University. Bio chip. Lab-on-chip devices are used to effectively analyze DNA. Moving parts make the chips expensive and fragile One way of transporting the fluid in the samples is through the use of electrokinetic effects.
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Biotechnology – BiochipModel Provided by Dr. MacInnesSheffield University
Bio chip • Lab-on-chip devices are used to effectively analyze DNA • Moving parts make the chips expensive and fragile • One way of transporting the fluid in the samples is through the use of electrokinetic effects
Electrokinetic effects • Electroosmosis • Due to charged groups on the surfaces of the wall a charged solution will be formed near the walls • The liquid in the charged double layer is displaced by the electric field generating a so-called electroosmotic flow • Electrophoresis • Water is dragged by the sodium ions, which can coordinate more water molecules than the chloride ions in the solution • This type of process is calledelectrophoretic flow
Biochip – Problem definition Chip geometry • We will use a 2D approximation of the geometry channel width is 0.25 mm
Biochip – Problem definition Modeling equations • Incompressble Navier-Stokes equations for fluid flow • Fluid parameters: • = 1000 kg/m3 • = 10-3 kg/ms • = 0.11845 S/m • Current balance for the potential
Biochip – Problem definition Boundary Conditions diffuse layer, wall Fluid parameters: w = 80.2*8.854*10-12 As/V/m 0 = 0.1 V
Biochip – Problem definition Test configurations
Biochip - Results mode A mode B Results, flow field
Biochip - Results Results, edge effects mode A
Biochip - Results Results, edge effects • COMSOL Multiphysics transport model mode B