A finger actuated POCT microfluidic chip for on-site multiple detection

Schematic illustration of the finger actuated microfluidic chip. Schematic illustration of (a) the fabrication of the microfluidic chip by standard soft lithography , (b) the finger-actuated microfluidic chip, (c) the design of the finger actuated microfluidic chip, (d) the microfluidic chip made by PDMS and (e) exploded view illustration of the finger actuated microfluidic chip. Schematic illustration of (a) the working principle for single detection, (b) the working principle for multiple detection, (c) the micro-mixing inside the microchannel , (d) the dye mixing detection. • Enables rapid on-chip sample input, mixing, pipetting, diversion and detection. • A novel pumping and checking structure avoid the leakage during fluid pumping and mixing. • A novel figure-powered microfluidic device for on-site multiple detection. • The develop of serpentine microchannel improves the micro-mixing and promote the chemical reactions. Point of care testing (POCT) is of great significance in the fields of biological, chemical, and medical treatment, and the increasing interests are focused on the detection of POCT intelligent detection chip, which behaves characteristics of rapid, simplified, and portable properties rather than limited use of site and operation technology. Various methods have been developed for different detection at the same time, but these are not user-friendly. Here, we developed a microfluidic device aiming at multiple detection operated by finger actuation, which integrates mixing, pipetting, sorting and detecting. The inflow of mixed suspension was maneuvered by special stop valve for further multiple detection, and the mixing efficiency and the pressure drop in the serpentine mixing channel were optimized to achieve reliable mixing results. The numerical analysis of the effect of the inlet velocity shows that the mixing efficiency of the system reaches as high as 99.6 % when the Re value is in the range of 0.1 ∼ 100. The performance of the system was verified experimentally, and the glucose and glucose oxidase reagents were successfully guided into a single drive chamber for multiple tests using less than 15 µL of glucose and glucose oxidase in 240 s. In this study, the working principle of the novel pumping and checking geometry was developed and the multiple detection process of the whole chip are systematically investigated. The mixed solution is always continuously and accurately pumped to the determined detection area by pressing the check valve button, providing a potential method for on-site multiple detection.