Metal Chelation Assisted Deposition of Polydopamine on Human Hair: A Ready-to-Use Eumelanin-Based Hair Dyeing Methodology

The study explored a novel hair dyeing method using polydopamine and ferrous ions to create eumelanin-based pigments for gray hair coloration. This method aimed to provide a safer alternative to traditional dyes, which often contain harmful chemicals like p-phenylenediamine (PPD). The results showed that polydopamine effectively coated hair fibers, resulting in stable and natural-looking color. Toxicity tests on ICR mice indicated that polydopamine-based dyes were less toxic compared to PPD. The findings suggested that this method could be a promising, safer, and more sustainable option for hair dyeing.