O o d h e a d p u b L i s h I n g L i m I t e d

Key words: wool, keratin, biomaterials, biopolymers.
14.1
Introduction
When considering the application of wool beyond textiles and fibres it is
important to first consider the materials from which wool is made up. Once
the macroscopic structure as a fibre is not fundamental in defining the
application, then it comes down to the base materials from which the fibre is
formed to define the relevant applications.
Both macroscopic and microscopic characteristics of the wool fibre have
been extensively reviewed (Gillespie, 1983; Marshall et al., 1991). By far
the most important material in this consideration is keratin protein, defined
by the US National Library of Medicine as ‘A class of fibrous proteins or
scleroproteins important both as structural proteins and as keys to the study
of protein conformation. The family represents the principal constituent of
epidermis, hair, nails, horny tissues, and the organic matrix of tooth enamel.’
It is clear from this definition that keratin proteins, in various forms, are
widely present in biological systems, in hair, skin, nails and other tissue.
This widespread occurrence in nature, as a tough, physical material from
which to build structures, is of significance when considering advanced
applications of wool. The tenacity of wool, the resilience of our nails, the
barrier characteristics of our skin, tell us much about the features that we can
look for in advanced applications of wool-derived keratins. While keratin
may account for up to 95% of the dry matter of a wool fibre, the other
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Advances in wool technology
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components are also of note for their interesting characteristics. Considered
as an ordered collection of elongated cells, rich in multiple types of keratin
proteins, the wool fibre structure is brought together by the cell membrane
complex, the material that defines the cell boundaries and a key element in
keeping the cells together in a strong and ordered fibrous alignment. Lipids
found within this region of the fibre resemble strongly those in the skin, and
as such they find ready application in topical skin products to supplement
skin lipids and improve a range of important cosmetic skin parameters (de
Pera et al., 2000).