Digital Microfluidic System with Dual Half-Moon Electrodes

With the rapid advancement of digital microfluidic technology, this study presents the design and fabrication of a PCB-based digital microfluidic system aimed at reducing chip driving voltage and manufacturing costs while enhancing droplet manipulation performance. The system integrates peripheral modules to establish a complete digital microfluidic platform. A novel double half-moon serrated electrode is proposed, which provides enhanced droplet driving force and enables multidirectional droplet movement through flexible electrode arrangement. Three electrode configurations with different scaling parameters were designed and experimentally evaluated. The results demonstrate that the electrode with a scaling parameter of A = 1 exhibits the best driving performance. At an applied voltage of 120 V, the average droplet velocities in the transverse and longitudinal directions reached 1.18 mm/s and 0.98 mm/s, respectively, while at 200 V they increased to 2.57 mm/s and 1.88 mm/s. Compared with conventional rectangular and serrated electrodes, the proposed electrode structure effectively improves droplet driving capability. This work provides a low-cost and high-performance solution for the development of portable and integrated digital microfluidic systems.