Development of a microfluidic electroosmosis pump on a chip for steady and continuous fluid delivery

Infusion therapy is the most common form of therapy used in health care. However, the existing infusion devices show higher flow discrepancies as flow rates decrease to a few nL min^-1. As a result, dosing errors can contribute to the morbidity and mortality of patients. In the scope of project 18HLT08 MeDD II - Metrology for drug delivery, this investigation aims at the development of a silicon microchip flow pump capable of steadily and continuously dispense very low flow rates of a few nL min^-1. The fabrication methodologies explored here use a combination of typical cleanroom micro/nanofabrication techniques and off-the-shelf equipment. Preliminary tests show flow rates as low as 45 nL min^-1 can be obtained in this microfluidic electroosmotic pump. The experimental flow rates are in good agreement with results predicted by multiphysics simulation, with less than 8% deviation ratio. This cost effective electroosmotic micropump has the potential to act as a steady and continuous drug delivery system to neonatal patients as well as to organs on chip (OoC), determining the stability of the shear stress imposed on the cells or the right cell culture medium conditions.