Computational and experimental investigation of microfluidic chamber designs for DNA biosensors

An important and critical characteristic for continuous monitoring using DNA biosensor is the microfluidic design. Some of the significant functions of microfluidic structures used in DNA biosensors are sample manipulation, effective and rapid reaction and ultra-low detection limit of the analyte. This study explores different designs and parameters of microfluidic microchambers. The selection of the appropriate geometrical design and control of microfluidic parameters are highly important for the optimised performance of the biosensor. Several combinations of different shapes of microchambers are designed and assessed computationally. Flow parameters such as average velocity, pressure drop, flow rates and shear parameters are critically assessed at different cross-sections within the microchamber.

Optimised design of the microchamber is selected based on optimal rinsing, minimum flow shear, avoidance of slow zones, simple geometry and homogenous distribution of the analyte target. Steady and unsteady laminar flow simulations were performed using a commercial Computational Fluid Dynamics software. A range of different geometrical shapes were assessed using parametric studies and a design optimisation analysis. 3D printing technology was used to construct and evaluate the optimised designs in combination with experimental investigations which were carried out and the optimum design was selected and characterised.