Acknowledgements
The authors are grateful to Erin Lee for preparing the samples for mass
spectrometry, Evelyne Maes for helpful comments during the preparation
of the manuscript and Professor David Parry of Massey University for
helpful discussions. The work was funded by the
Wool Research Organisation of New
Zealand (WRONZ) and the Ministry of Business Innovation and Employment
through the New Materials from New Zealand Wool partnership program via
Wool Industry Research Limited.