Microfluidic-Based Dispenser for Sub-Microliter Pipetting

In the study, we report a microfluidic-based dispenser fabricated by standard soft lithography of PDMS (polydimethylsiloxane) for sub-microliter range precise pipetting. The key feature of the microfluidic-based dispenser is the incorporation of a pressure-generating unit providing the driving force for precise and quick aqueous liquid sampling and pipetting. The microfluidic-based dispenser features in the elegant control of the releasing time of the air pressure in the pneumatic chamber of the pressure-generating unit causing the underside membrane to provide suction, thus contributing to precise pipetting of aqueous liquid volumes ranging from 0.05 mul to 0.45 mul (the minimum unit is 0.05 mul) achieving the multi-volume dispensing capability. Therefore, the developed microfluidic-based dispenser can dispense multiple sub-microliter aqueous liquid volumes precisely and quickly and is promising for further micro-total-analysis-systems in the field of drug dosing or other biomedical applications.