Synthesis and characterization of PVP microneedle patch using metal bioelectrodes for novel drug delivery system

In this study, we prepared a novel microneedle patch using metal bioelectrodes that provide excellent mechanical properties, drug-delivery efficiency, and biocompatibility at the same time. The biocompatible polyvinylpyrrolidone (PVP) based microneedle patch was prepared using gamma rays. The back side of the PVP based microneedle patch were coated with gold or silver as bioelectrodes using the thermal evaporation method to maximize and control the efficiency of drug release. The Au or Ag-coated microneedle patch has enough mechanical properties to successfully penetrate the skin. In addition, it was confirmed using a Franz cell that the amount of drug released from a drug-loaded microneedle patch was maximized by thermal or electrical stimulus. The drug-release efficiency increased more than 7.9 times compared to a flat PVP patch (without applying electricity) when 3 V was applied. In addition, when ~40 °C heat were applied, the drug-release efficiency of the Au- and Ag-coated PVP based microneedle patches improved about 5.3 times compared to a flat PVP patch at room temperature. These excellent properties of our metal-coated PVP based microneedle patches can be used not only in whitening or anti-wrinkling cosmetics, but also as medical drug-delivery systems to treat such as hypertension, diabetes, and arthritis.