Design and analysis of paper-based microfluidic channel to detect potassium concentration in human sweat.

This paper describes an idea of a simple analytical microfluidics device that is used to infer levels of potassium concentration in a sample. The project is based on a paper-based device with capable barriers and a 50 mm microchannel which is subjected to wick the solution containing potassium salts. The wicking rate and the wicking time is calculated. The barrier is made out of cheap processes by using paraffin wax which is heated to 70 ^oC for about 10 minutes and then carefully applied and infused into the filter paper for required length. Various simulations are carried out and studies were analysed by using COMSOL Multiphysics to understand the wicking phenomenon and the impact of filter paper parameters such as porosity, pore size and pore distribution index on wicking rate. The dimensions of the microstrip is inferred from the simulation results and the designed strip is tested with KOH solution of closely varying concentrations. A common time is set and the wicking rate and fluid uptake is observed. It is realised that the output shows that wicking rate is inversely proportional to the concentration of solution. [ABSTRACT FROM AUTHOR]