STRUCTURAL CHARACTERISTICS OF DIFFERENT TYPES OF KERATIN FIBRES

Abstract

Hair is a composite protein fibre of natural origin, which is characterised by heterogenic morphological structure and consists of three concentric layers: cuticle, cortex and core. Hair consists of mainly two groups of proteins - α-keratins with low content of sulphur, the molecular weight of which fluctuates within 40–60 kDa and matrix proteins with the molecular weight from 10 to 25 kDa. α-keratins form microfibrillar structure, known as intermedial filaments which give hair elasticity and strength, and matrix or keratin-associated proteins have the function of a specific glue, connecting said filaments. The aim of the work is to determine structural characteristics of keratin fibres, different in their morphological structure, in order to select optimal approaches to creation of novel biocomposite materials. Samples of human hair, sheep wool and rat hair were analysed. It was shown that keratin fibres of different morphological structure differ as to their amino acid composition, namely in content of lysine, leucine, histidine, tyrosine, cystine, arginine, aspartic acid and glycine. It was found that the ratio between the crystalline and amorphous phases of fibre grows in the series human hair®rat hair ®sheep wool and constitutes respectively 1.9; 2.1; 2.3. It was proved that the content of protein with high content of tyrosine and glycine is twice higher in rat hair than in wool fibre. The said proteins were not identified in human hair