具备连续液滴引入引出功能的数字微流控装置实现按需式核酸样本制备OA

Digital microfluidic(DMF)devices based on electrowetting-on-dielectric(EWOD)actuation offer programmable liquid-handling capabilities and provide a flexible,efficient platform for batch sample processing.However,current DMF devices lack continuous liquid introduction and extraction functions,which limits their potential for high-throughput sample handling.To overcome this limitation,a DMF device with continuous droplet introduction and extraction interfaces was developed and applied to on-demand nucleic acid sample preparation.The two-plate DMF device incorporated a custom-designed top plate featuring a T-shaped channel on its bottom surface:a main channel connected to liquid inlet/outlet ports and branch channels linked to the electrode array on the bottom plate.During liquid introduction,water-in-oil droplets were introduced into the inlet,then driven pneumatically into the main channel,and finally transferred via EWOD through the branch channels to the electrode working zones.For liquid extraction,individual droplets were first moved by EWOD into the main channel and then expelled from the outlet via pneumatic pressure.This DMF device was applied to preparation of hepatitis B virus(HBV)DNA samples.The system allowed sample processing immediately upon reception,and the entire workflow from sample introduction to nucleic acid extraction could be automated.In continuous operation mode,the average processing time per sample was less than 7 min,enabling a throughput of up to 9 samples per hour.Quantitative PCR analysis confirmed the reliability of nucleic acid extraction using this DMF device.With compact design,flexible operation,and rapid response,this DMF device offered an ideal tool for efficient sample processing in decentralized healthcare settings.