The biochip is a solid, miniature substrate that may accommodate several test locations, allowing for concurrent biochemical investigations and reactions. In essence, it is a “miniaturized laboratory” or “microarray” where certain bio-molecules are immobilized on a surface. Over the past few decades, Continuous-Flow Microfluidic Biochips (CFMB) has been widely used to automate lab processes in molecular biology and biochemistry. In the recent years the lab automation in the field of molecular biology and biochemistry has been progressed through the development of Digital Microfluidic Biochips (DMFBs). DMFB was rapidly used during 2019 coronavirus disease pandemic (COVID-19). In critical diseases identification, the volume of the reagent or the samples play important role. The major challenges in the DMFB technology such as fixed electrode structure, variable sample or reagent size, non availability of in-process error recovery, limited sensor integration and high cost of production makes the conventional DMFB biochips less popular now a days. To circumvent the associated problems with DMFBs, the researchers came up with new solution is the field of microfluidic biochips is called Micro-Electrode-Dot-Array (MEDA)-based biochips. In this work a comprehensive review of the studies has been made regarding architecture, sample preparation, routing algorithm and synthesis of three different kinds of microfluidic biochip technologies. To begin the review, 327 research papers were chosen from the different academic databases within a span of 55 years starting from 1971. After deploying comprehensive screening process, this review considered 188 studies based on the relevance and importance. The different methodologies, benefits, and shortcomings of microfluidic biochip technologies have been lucidly elaborated in this paper which will be beneficial for biochip researchers.
