Over the last few years, microfluidic biochip has quickly come out as a promising alternative to conventional bench-top laboratory equipment for biochemical and biomedical analysis. Convenient sample preparation is essential for the efficacy of laboratory procedures such as protein and glucose analysis and pharmaceutical research. In this process, the primary reactant is diluted with buffer fluid or more than one reactants are diluted in the proper ratio to ensure subsequent bioassay operations are free of errors. In this paper, a prime factorization-based mixing method is proposed for micro-electrode dot array (MEDA)-based biochip to build the mixing tree to generate the target sample for different biochemical experiments. The simulated result demonstrates that the proposed technique minimizes the mixing/dilution operations and also reduces the consumption of raw reactants compared to the contemporary approaches.