Tea Tree Oil Concentration in Follicular Casts After Topical Delivery: Determination by High-Performance Thin Layer Chromatography Using a Perfused Bovine Udder Model

In a study from 2005, various formulations of tea tree oil, known for its antimicrobial properties and used in treating acne vulgaris, were applied to bovine udder skin to measure their uptake into hair follicles. The study utilized a cyanoacrylate method to collect follicular casts and high-performance thin layer chromatography to quantify the content of terpinen-4-ol, a major component of tea tree oil. Results showed that the follicular accumulation of tea tree oil varied across formulations, with microemulsion having the highest concentration at 0.43 +/- 0.01%, followed by liposomal dispersion at 0.41 +/- 0.009%, multiple emulsion at 0.21 +/- 0.006%, and colloidal bed at 0.16 +/- 0.005% by weight. This research was the first to quantify tea tree oil concentration in hair follicles.