(346e) The Kinetics of Diffusion in Keratin Fibres Using Mass Spectrometry

N. Ali¹, D.R. Williams¹, J. Marsh ² and S. Godfrey³

¹Surface Particles Engineering Laboratory, Department of Chemical Engineering

Imperial College, Kensington, London SW7 2BY

² The Procter & Gamble Company, 11810 East Miami River Road, Cincinnati, Ohio 45252

³ Researchand Development, Procter & Gamble, Darmstadt Germany.

Abstract

Over the years there has been considerable progress in understanding the structure and properties of hair. However, we still do not fully understand about the structure of hair and the penetration chemistry of actives in the hair.

Hydration of hair, for example, is a fundamental process. It governs swelling behaviour, structure, diffusion rates and mechanical properties of hair. Despite its importance, keratin water interactions (hydration) are poorly understood. This is particularly true for hydration along single hair fibres and across hairs from different body sites, genders, ethnicities and ages. Addressing these key knowledge gaps will allow us to unlock critical insights to enable innovation.

Hydration of hair, for example, is a fundamental process. It governs swelling behaviour, structure, diffusion rates and mechanical properties of hair. Despite its importance, keratin water interactions (hydration) are poorly understood. This is particularly true for hydration along single hair fibres and across hairs from different body sites, genders, ethnicities and ages. Addressing these key knowledge gaps will allow us to unlock critical insights to enable innovation.

In this study, the time dependent mass uptake of solutes has been demonstrated using Gas Chromatography Mass Spectrometry (GC-MS). The effect of solute concentration and temperature on the kinetic uptake of monoethanolamine by hair fibres has been investigated. Diffusion coefficient has been determined using Crankâ??s equation for an infinite cylinder.