Research on conductive polymer microneedles with adjustable dissolution rate

Dissolvable polymeric microneedles have gained significant attention in recent years as a promising transdermal drug delivery method due to their simple fabrication and lack of medical waste after use. However, traditional polymeric microneedles possess several notable drawbacks, including insufficient mechanical strength, difficulty in effectively penetrating the skin barrier, limited drug loading capacity affecting therapeutic outcomes, and uncontrollable drug release rates leading to unstable efficacy. In this paper, a conductive polymer microneedle with an adjustable dissolution rate is proposed. The dissolution rate of microneedles can be adjusted by controlling the current so as to control the drug release rate and realize the controlled drug release truly. The PVA-Ag and PVP-Ag lidocaine-loaded microneedles demonstrated good puncture performance and nearly complete dissolution within 10 min in a simulated body fluid environment. The dissolution rate was significantly accelerated under electrical stimulation. The microneedles showed good biocompatibility, and under the application of a 3 V voltage, the drug delivery efficiency of PVP-Ag lidocaine microneedles reached 85% within 5 min, while PVA-Ag lidocaine microneedles achieved up to 90%.