Dissolution and mixing of flavin mononucleotide in microfluidic chips for bioassay

Dissolution and mixing of flavin mononucleotide (FMN), which activates a luminescent reaction, were considered in various designs of microfluidic chip for pollution analysis of liquid samples. The aim was to determine the velocity mode of fluid flow ensured the uniform distribution of the FMN in the reaction chamber. Simulation of concentration distribution of FMN in various designs of microfluidic chips was conducted. It was shown that the passive mixing techniques based on the constant flow rate didn't provide mixing of FMN in acceptable time (3 seconds). The most efficient mixing was achieved using variable flow rate with a gradually increasing frequency of oscillation.