Human hair: color changes caused by daily care damages on ultra-structure

UV–vis spectra as an alternative to the Lowry method for quantify hair damage induced by surfactants

“…Scanavez et al [1] showed that this extraction takes place by a degradation process that involves CMC and endocuticle dissolution, detachment of cuticle fragments and subsequently melanin granules extraction from the hair cortex.…”

“…It is well known that hair is damaged by daily care and washing hair is one of the processes responsible for these damages [1]. Human hair fiber is composed mainly by ␣-keratin and is divided in three basic structures, outside-in: cuticle, cortex, and, in some cases, medulla.…”

“…Surfactants remove extractable substances from the endocuticle and the cortex, making melanin granules susceptible to removal http://dx.doi.org/10.1016/j.colsurfb.2014.09.035 0927-7765/© 2014 Elsevier B.V. All rights reserved. [1,18]. Moreover, sodium dodecyl sulfate (SDS) causes hair cuticle protein denaturation [19] and extracts twice more proteins from hair than water [20].…”

“…The Lowry method, widely used to quantify hair protein loss [1,20,21], estimates colorimetrically the amount of protein in aqueous solution [22]. On one hand, the solution without proteins must display no color, because the solution with proteins display a blue coloration ( max = 750 nm) proportional to proteins concentration.…”

Inorganic replication of human hair and in situ synthesis of gold nanoparticles

“…Some parts of the border of each "squama" were slightly broken (pointed by the white arrows in Fig. 1(b)) [7] and were not as smooth as its central part. Each cuticle cell was 0.5−1.0 µm in thickness and ca.…”