Unveiling the Link Between Surface Physicochemistry and Nanomechanical Behavior in Bleached and UV-Irradiated Human Hair Fibers

March 2026 in “ Journal of the mechanical behavior of biomedical materials/Journal of mechanical behavior of biomedical materials ”

Raphael C.L. Machado, Flávio B. Camargo Júnior, Wagner Vidal Magalhães, Géssica F.D. Oliveira, Alessandra Mari Goshiyama, Maria Cecília B.S. Salvadori

bleached hair UV irradiation human hair fibers surface physicochemistry nanomechanical behavior Atomic Force Microscopy Energy-Dispersive X-ray Spectroscopy bleaching UV damage

Studysummary In this study, researchers found that hair fibers exposed to bleaching and UV irradiation displayed significantly more damage, including increased adhesion and surface heterogeneity, compared to untreated hair, highlighting a synergistic degradation pathway affecting the hair cuticle's integrity.

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This study investigates the degradation of human hair fibers, focusing on the relationship between surface physicochemistry and nanomechanical behavior. Using techniques like Atomic Force Microscopy and Energy-Dispersive X-ray Spectroscopy, the research found that bleached hair fibers show increased adhesion and heterogeneity compared to untreated hair. The study highlights that combined bleaching and UV irradiation significantly amplify hair damage, suggesting a synergistic degradation pathway. These findings emphasize the importance of nanoscale mapping for evaluating cosmetic treatments and have potential applications in forensic and clinical diagnostics by identifying structural and chemical anomalies in hair.

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