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Updated: Oct 10, 2025

Author Spotlight: Exploring Intrinsically Disordered Protein Dynamics Through NMR Relaxation Experiments
Published on: November 1, 2024
Molecular interaction and partitioning in α-keratin using 1H NMR spin-lattice (T1) relaxation times
Susannah Molisso1, Daryl R Williams2, Oscar Ces1
1Institute of Chemical Biology, Department of Chemistry, MSRH, Imperial College London, White City Campus, 80-92 Wood Lane, London W12 0BZ, UK.
Abstract:
The interactions between small molecules and keratins are poorly understood. In this paper, a nuclear magnetic resonance method is presented to measure changes in the 1H T1 relaxation times of small molecules in human hair keratin to quantify their interaction with the fibre. Two populations of small-molecule compounds were identified with distinct relaxation times, demonstrating the partitioning of the compounds into different keratin environments. The changes in relaxation time for solvent in hair compared with bulk solvent were shown to be related to the molecular weight (MW) and the partition coefficient, LogP, of the solvent investigated. Compounds with low MWs and high hydrophilicities had greater reductions in their T1 relaxation times and therefore experienced increased interactions with the hair fibre. The relative population sizes were also calculated. This is a significant step towards modelling the behaviour of small molecules in keratinous materials and other large insoluble fibrous proteins.
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