Study of reaction-diffusion controlled mass transport in stopped-flow fluidics for spatiotemporal multiplexing

Abstract

Integration of biochemical reaction networks (BRNs) with biosensor platforms has emerged as a technological niche overcoming challenges related to the loss of sensitivity and selectivity in biological media. Optimal operation of BRNs in microfluidics requires control over reaction-diffusion dominated mass transport, heavily influenced by fluidic parameters. In this work, we study and design an on-chip platform combining a programable unique molecular amplification as BRNs with nanoscale biologically sensitive field-effect transistor (BioFET) arrays, which employs a physical diffusion barrier to gain spatial and temporal control over mass transport. Computational and numerical approaches, such as finite element and finite volume methods, were implemented to solve partial differential equations numerically after domain approximation by numerous finite elements. The focus on geometrical optimizations of fluidics is aimed at mass transport to occur with precise spatial and temporal control toward BioFET-arrays. Adopting a 0.5 pM limit-of-detection (LoD) for biochemical monitoring of BRNs via a single-stranded deoxyribonucleic acid (ssDNA) output, we show that it was possible to compartmentalize the mass transport spatiotemporally without crosstalk, which can be of critical advantage for using biosensor arrays in order to realize simplified multiplexed point-of-care biosensors.