Fabrication of Microneedles by Pulsating In Situ Dried Electrostretching for Transdermal Drug Delivery

This paper introduces a novel pulsating in situ dried electrostretching (PIDES) technique for the fabrication of microneedles (MNs) for transdermal drug delivery. This method utilizes pulsed voltage to induce electrohydrodynamic forces that stretch and freeze a polymer droplet into a conical shape with a micrometer-scale tip. With the effects of solvent evaporation, the polymeric droplet is in situ stretched into a conical shape and solidified, transforming into a sharp MN, suitable for transdermal drug administration. Penetration and mechanical tests confirm that the MNs possess sufficient sharpness and strength for effective skin penetration applications. Additionally, curcumin loading and in vitro release tests with different concentrations demonstrate the MNs' ability to carry drugs and exhibit effective controlled release profiles. These findings highlight PIDES as a promising, low-cost, and simple approach for the development of painless and efficient transdermal drug delivery systems.