Spectroscopy as a tool to evaluate hair damage and protection

Abstract

OBJECTIVE: Methods that can be used to analyse hair damage and to support a claim of hair protection are important for the cosmetic industry. There are many approaches available, but they are usually laborious and expensive. The researchers propose a simple fluorescence method that is based upon the emissive properties of damaged hair. METHODS: Hair fluorescence was observed when using both fluorimetry and microscopic procedures. The method was developed by comparing native hair with hair that was damaged by UVA and visible light. RESULTS: Spectroscopic properties (absorption and emission) of hair in the visible range are presented. The changes in the emissive properties of hair during irradiation were characterized and they were correlated with photobleaching, which is due to the generation of singlet oxygen. Emissions were also obtained in the hair shafts that had been previously treated with chamomile extract and this treatment was able to avoid hair bleaching. CONCLUSION: The emissive properties of hair in the visible range can be used as a tool for the evaluation of hair damage and protection. This method can be useful as a tool in order to claim substantiation. R esum e OBJECTIF: Les m ethodes pouvantêtre utilis ees pour analyser les dommages caus es aux cheveux et pour soutenir une revendication de protection des cheveux sont importantes pour l'industrie cosm etique. Il existe de nombreuses approches disponibles, mais elles sont g en eralement laborieuses et coûteuses. Les chercheurs proposent une m ethode simple de fluorescence qui repose sur les propri et es emissives de cheveux abîm es. M ETHODES: La fluorescence des cheveux a et e observ ee en utilisant des proc edures de fluorim etrie et de microscopie. La m ethode a et e d evelopp ee par comparaison de cheveux de Br esiliens avec des cheveux endommag es par l'action des UVA et de la lumi ere visible. R ESULTATS: Les propri et es spectroscopiques (absorption et emission) des cheveux dans le domaine visible sont pr esent ees. Les changements dans les propri et es emissives des cheveux au cours de l'irradiation ont et e caract eris es et ont et e corr el es avec le photoblanchiment, qui sont dûs a la g en eration d'oxyg ene singulet. Des emissions ont egalement et e obtenues dans les tiges capillaires pr ec edemment trait es a l'extrait de camomille et ce traitement a pu eviter le blanchiment des cheveux. CONCLUSION: Les propri et es emissives des cheveux dans le visible peutêtre utilis e comme outil d' evaluation des dommages et de la protection des cheveux. Cette m ethode peutêtre utile en tant qu'outil pour une justification des revendications.The chamomile extract, generously provided by Farma Service Bioextract Ltda, was diluted in a hydroglicolic vehicle (HG) to 10% (v/v). The hair shafts were immersed in this solution for 30 min. The excess liquid was removed by absorbent paper and the samples were exposed to photodamage by the ultraviolet or visible light. Processing and the obtention of the hair cross sectionsThe hair strands were embedded with...

Rice Derivatives in Hair Protecting

“…Recently, spectroscopy is proving to be a good tool for evaluating the effects of treatments that are harmful to the hair or to the protective effect of cosmetics [15]. FT-IR imaging analysis has found applications in the evaluation of bleaching processes [16], and the ATR FT-IR was useful in identifying cosmetic residue on a single human hair [44]; thus, it was suggested for forensic hair analysis [45,46].…”

“…The same evaluations can be carried out through spectroscopic techniques. Pavani et al [15] applied fluorescence spectroscopy for the assessment of hair photo-induced damage. Fourier transform infrared spectroscopy can be applied for the detection of molecules that bind to the hair, for the study of structural and morphological variations of the hair due to bleaching and/or coloring and for the study of the state of hydration induced by the application of a conditioning product [11,16].…”