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Description
Microfluidic systems have become an essential platform for biomedical and drug delivery applications due to their ability to precisely manipulate minute volumes of fluids within microscale channels. Conventionally, polydimethylsiloxane (PDMS) microfluidic devices are fabricated using SU-8 molds produced through photolithography, which requires cleanroom facilities, expensive chemicals, and complex fabrication procedures. This study presents a low-cost and simplified fabrication approach by replacing the conventional SU-8 mold with a stereolithography (SLA) 3D-printed mold for the fabrication of PDMS microchannels integrated with a non-contact electrode for electroosmotic flow (EOF) applications. The fabricated microchannel was experimentally evaluated using sodium chloride (NaCl) solutions at different concentrations to investigate its fluidic performance and electroosmotic characteristics. Leakage and flow stability were first assessed by varying the syringe pump flow rate from 2 to 12 mL/h, confirming stable fluid transport without leakage throughout the tested range. Electroosmotic performance was subsequently evaluated by applying voltages between 1 and 2 V revealed that the conventional contact electrode configuration exhibited a 15–30% reduction in flow velocity with increasing NaCl concentration. In contrast, the proposed non-contact electrode demonstrated a linear increase in electroosmotic flow velocity with increasing applied voltage, achieving an approximately 88% enhancement in flow performance compared with the contact electrode configuration. The improved electroosmotic performance is attributed to the elimination of direct electrode-fluid interaction, thereby minimizing electrode degradation and electrochemical reactions while maintaining efficient electroosmotic actuation. The proposed fabrication method provides a simple, cost-effective, and reliable alternative for developing electroosmotic microfluidic devices and demonstrates strong potential for integration into portable biomedical and controlled drug delivery systems.
