Master's Student Thesis Abstracts > Olivia Kim: Transdermal Patches Targeting Acne Vulgaris
Development of Photoprotective Transdermal Patches for The Controlled-Release of Vitamin C Targeting Acne Vulgaris and Hyperpigmentation
Acne vulgaris (AV) is a common skin condition that causes inflammation, pain, and psychological burden on individuals. Post-inflammatory hyperpigmentation (PIH) is an associated skin condition that proceeds the onset of AV. In-office procedures to treat AV and PIH may be inaccessible to those afflicted with these conditions, and available over-the-counter (OTC) treatments can cause unwanted side effects like sensitivity and irritation. A popular remedy is hydrocolloid patches, which are transdermal patches (TDP) designed to promote healing of AV. However, these patches do not treat PIH caused by AV. Vitamin C, known as L-ascorbic acid (LAA), is clinically shown to alleviate AV and improve PIH. However, it is highly susceptible to degradation upon exposure to air and ultraviolet (UV) radiation.
The aims of this study were to: (1) formulate a UV-blocking TDP backing film; (2) assess the efficacy of these films to prevent LAA degradation; and (3) create a delivery system to mediate a controlled release of LAA. Thermoplastic polyurethane (TPU) was cast with varying ratios of zinc oxide (ZnO), demonstrating greater UV protective qualities with increased amounts of ZnO. Electrospun polycaprolactone (PCL) and polyvinyl alcohol (PVA) mats also added UV protection. TPU films with ZnO reduced LAA degradation by 76% compared to those without ZnO. The encapsulation of LAA in B-cyclodextrin (B-CyD) was successful and the controlled release profile was studied over 10 h. The extended-release study revealed that the release kinetics of this system did not exhibit burst release and instead closely followed a zero-order model, with R2 = 0.9882. Over 10 h, 55 ± 2% of the LAA was released at an average rate of 0.53 ± 0.12 mg/h for the first 5 h and 0.31 ± 0.31 mg/h for the last 5 h. These results indicate that TDPs with ZnO loaded TPU backing films and LAA-loaded B-CyD are a promising system to protect LAA from degradation and enable the controlled release of LAA to treat conditions such as AV and PIH.