Fabrication and analysis of hollow microneedles and polymeric piezoelectric valveless micropump for transdermal drug-delivery system

This study presents the fabrication and analysis of silicon hollow microneedles and polymeric piezoelectric valveless micropump for microelectromechanical (MEMS)-based transdermal drug-delivery (TDD) system. The proposed TDD system consists of integrated control electronics and MEMS devices such as micropump, microneedles, blood pressure sensor and fluid flow sensor. Microneedles and micropump are the most essential and critical components of the proposed TDD system. Mechanical strength of microneedles has been investigated in structural analysis. Inductively coupled plasma technology has been used to fabricate high aspect ratio silicon hollow microneedles. The numerical analysis of micropump has been done by building three-dimensional electro-fluid–solid model. The experimental performance of fabricated polymeric piezoelectric valveless micropump with different pump chamber diameters has been characterised in terms of actuator deflection and flow rate at different operational parameters.