Autor(es): Chen, Xiangcheng ; Liu, Lei ; Guo, Xinrui ; Wang, Hongbo ; Cavaco-Paulo, Artur ; Su, Jing
Data: 2025
Identificador Persistente: https://hdl.handle.net/1822/98481
Origem: RepositóriUM - Universidade do Minho
Assunto(s): Color fastness; Commercial dyes; Hair health; Hematoxylin dyes; Laccase
Traditional hair dyes pose significant health and environmental risks due to toxic components like p-phenylenediamine (PPD) and exhibit suboptimal color fastness despite their widespread use. To overcome these limitations, we introduce an eco-efficient enzymatic hair dyeing strategy based on laccase-catalyzed polymerization of hematoxylin, utilizing atmospheric oxygen as a green oxidant and generating water as the sole byproduct. Crucially, during in-situ polymerization, copper ions in laccase active center chelate with hematoxylin monomers bound to the hair surface, forming a stable polymeric coating that significantly enhances color durability. The optimized dyeing process achieves intense coloration (E = 53.18), rivaling commercial dyes in chromatic performance, while demonstrating exceptional wash fastness (97 % color retention after 50 washes). Furthermore, this uniform hematoxylin polymer coating was validated through rigorous biosafety assessments, and the mechanical performance test indicates that this colored coating can effectively enhance the strength of hair fibers. Notably, the dyed hair additionally exhibits robust antioxidant activity and UV-shielding properties, mitigating photoaging risks.
