Dissolvable polymeric microneedles (DPMNs) are promising transdermal drug delivery systems with minimal invasiveness and improved patient compliance. Incorporation of a small amount of graphene oxide (GO) in the biocompatible polymers for microneedle fabrication results in important new DPMN properties, that is, dramatically enhanced mechanic strength (10-17 times at 500 mg/mL GO), improved moisture resistance, self-sterilization, antibacterial and anti-inflammatory properties (demonstrated in vitro), and near-infrared light-activated controlled drug release (demonstrated in vitro and in vivo), which were exploited for the transdermal delivery of the chemotherapeutic, HA15, to melanoma-bearing mouse models. These new properties improve their efficacy of transdermal drug delivery and ease of use, enhance their capability of controlled drug release, enlarge the scope of the polymers that can be used for DPMN fabrication, prevent microbial contamination during storage and transportation, and reduce infection risk in clinical applications.
Keywords: graphene oxide; mechanic strength; photothermal effect; polymeric microneedles; self-sterilizing; transdermal drug delivery.