Synthesis and Validation of Functional Nanogels as pH-Sensors in the Hair Follicle

The study developed dendritic polyglycerol-based nanogels as pH sensors for hair follicles, using an ex vivo porcine ear model. These nanogels, sized between 100-250 nm, were synthesized via an inverse nanoprecipitation method and labeled with pH-sensitive dyes. The pH gradient within hair follicles ranged from 6.5 at the surface to 7.4 at a depth of 531 µm, with a sharp increase in the first 300 µm. The nanogels effectively measured pH changes and showed no toxicity in vitro on HaCat cells, indicating their potential for precise pH measurement and targeted drug delivery in hair follicles.