Ethnic hair: Thermoanalytical and spectroscopic differences

Abstract Background The aim of this study is to characterize and detect the possible differences among the hair of three different ethnicities: African, Asiatic and Caucasian. Materials and Methods The differences in water adsorption/desorption behaviour of hairs were studied using a thermogravimetr...

Descripción completa

Detalles Bibliográficos
Autores: Oliver, Marc Adrià, Coderch Negra, M. Luisa, Carrer, Víctor, Barba, Clara, Martí, Meritxell
Tipo de recurso: artículo
Estado:Versión aceptada para publicación
Fecha de publicación:2020
País:España
Institución:Consejo Superior de Investigaciones Científicas (CSIC)
Repositorio:DIGITAL.CSIC. Repositorio Institucional del CSIC
OAI Identifier:oai:digital.csic.es:10261/215448
Acceso en línea:http://hdl.handle.net/10261/215448
Access Level:acceso abierto
Palabra clave:Chemical analysis
Lipid
Hair growth/hair biology
Moisture content
Spectroscopy
Descripción
Sumario:Abstract Background The aim of this study is to characterize and detect the possible differences among the hair of three different ethnicities: African, Asiatic and Caucasian. Materials and Methods The differences in water adsorption/desorption behaviour of hairs were studied using a thermogravimetric balance and compared with the analysis of the lipid distribution and order using synchrotron‐based Fourier transform infrared microspectroscopy. Besides, the thermal thermogravimetry (TG) and differential scanning calorimetry (DSC) analyses on human hair were executed. Results Differences in the diffusion coefficients were evidenced. African hair exhibited increased permeability. Caucasian hair displayed a higher water absorption capability with increasing humidity but with a slow diffusion rate. The Asian fibre appeared to be more resistant to hydration changes. The spectroscopic analysis showed notable differences in the cuticle lipids. The African cuticle exhibited more lipids with a lower order bilayer. The outmost layer of Caucasian fibres contained more ordered lipids, and the Asian fibres show a very low level of lipids on the cuticle region. The DSC results indicate no difference in the thermal stability and TG showed higher water content in the Caucasian fibre and a possible lower cysteine disulphide bond content in the African hair matrix. Conclusion The triple approach demonstrated the permeability differences among the ethnic fibres and their correlation with the properties of their cuticle lipids. These differences could have particular relevance to the hair care cosmetic market.