Voltage driven electrowetting based microfluidic operations for efficient droplet routing in digital microfluidic biochips

Electrowetting based operation can be effectively used to enhance the performance throughput of the programmable lab-on-chips (LOCs). These chips are also known as digital microfluidic biochips (DMFBs). In this work, initially we have presented a study on the effect of external actuation voltage in various parameters like transport velocity and contact angles during droplet movement on DMFB, in the realm of surface hysteresis. Next, a greedy heuristic method is adopted in conjunction with droplet velocity lookup under varying range of voltage actuation to perform improved droplet routing on digital microfluidic biochips. Here a specified routing time, termed as latest arrival time (LAT) is calculated in an ideal case, without considering practical electrowetting effects. Then a stepwise voltage increment is performed through the droplet routing paths to reach the specified target location in time. Goal of the proposed method is to achieve a specified routing time for all the droplets towards their destinations. Experimental analysis ascertains the suitability of this technique in enhancing the throughput of an LOC in terms of transport time reduction, and elimination of any failed net during routing.