Polylactic Acid and Polycaprolactone Blended Cosmetic Microneedle for Transdermal Hispidin Delivery System

Abstract

Microneedles (MNs) are a new system of effective drug delivery that create micron-sized pathways to the epidermis or upper dermis regions of the skin. In this study, we developed coated-type microneedles for direct hispidin delivery to the skin. Hispidin is a well-known plant-derived antioxidant component showing antitumor, anti-inflammatory, antiallergic, antiangiogenic, antioxidant, hypoglycemic, hypolipidemic, and immunomodulatory activities. Polymeric blends of polylactic acid (PLA) and polycaprolactone (PCL) were casted as MNs to enhance skin permeability. PLA/PCL MNs exhibited the highest strength of 51.26 MPa with a width of ~200 ųm. Hispidin was directly coated onto the MNs with PLA/PCL blends to form delivery layers. Compared to the hispidin-only delivery layer, skin permeability of hispidin increased by over 50% when using agarose gel in in vitro tests. In a dose-dependent manner, hispidin coated on PLA/PCL MNs also showed a brightening effect, as well as anti-inflammatory activity at the gene and protein level in skin cell culture experiments. It also demonstrated antimicrobial activity, and showed no cytotoxicity to skin cells. These results suggest that the PLA/PCL MN system with hispidin may have great potential as a prototype platform for various drug delivery systems, allowing the development of more effective subcutaneous delivery of vaccines, oligonucleotides, insulin, and many other cosmetic applications.

Keywords

• microneedles
• hispidin
• drug delivery