Enhancing Digital Microfluidics: A Comprehensive Investigation into the Performance of Slippery Liquid-Infused Porous Surfaces

Slippery liquid-infused porous surfaces (SLIPS), formed by infusing porous Teflon with liquid lubricants, hold immense potential for applications in the field of digital microfluidics by enabling efficient droplet manipulation, preventing biofouling, and improving device performance. Despite diverse membrane-oil combinations reported to prepare SLIPS, systematic optimization for digital microfluidic application remains limited. This study investigates the fabrication and performance of SLIPS on two different Teflon membranes infused with three different oils (Silicone oil, Krytox oil, and Fluorinert FC40), focusing on their suitability for digital microfluidics. Among the tested combinations, the M1 membrane infused with silicon oil demonstrated superior performance, requiring a minimal actuation voltage of 170 V and achieving a droplet speed of 220 mm/min. In addition to excellent actuation properties, these SLIPS also effectively reduced biofouling challenges by minimizing bacterial and protein adhesion compared to untreated Teflon. This findings give valuable insights for engineering SLIPS fabrication with enhanced performance and antifouling characteristics, representing a crucial step toward robust, scalable digital microfluidics platforms.