Hair—the most sophisticated biological composite material

Abstract

Hair is a proteinaceous fibre with a strongly hierarchical organization of subunits, from the alpha-keratin chains, via intermediate filaments, to the fibre. The chemistry of the different morphological compartments results in exciting physical properties, including the hydrophilic/hydrophobic paradox. The present tutorial review will be of interest for protein- as well as polymer chemists, who want to learn from nature, and also for biochemists interested in the cytoskeleton and particularly in intermediate filaments; it also presents a scientific basis for hair cosmetics.

Morphology and side-chain dynamics in hydrated hard α-keratin fibres by 1H solid-state NMR

“…3a as a function of relative humidity (RH). The increase in the amount of water with increasing RH values follows a sigmoidal curve similar with that measured for moisture uptake [4]. In the dehydrated hard a-keratin the amount of rigid fraction has a low value as opposed to the hydrated keratin (Fig.…”

“…distinct from feather b-keratin found in avian and reptilian tissues [4]. As a component of skin, hair and nail tissues act as an interface between the living organisms and the external environment.…”

Remarkable shape memory effect of a natural biopolymer in aqueous environment

“…Natural smoothness can be recovered in the α-keratinous hair after washing, signifying the importance of water in hair care [51]. Such effect is also validated in luffa sponge as well as its individual fiber, which is mainly composed of cellulose, lignin and hemicelluloses [52].…”

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

“…All these structures are embedded by cell membrane complex (CMC), the only continuous phase in hair fiber [2]. Another component, which gives color to pigmented hair, is the melanin granules dispersed in the cortex [3].…”