Synopsis

Objective:
Methods such as differential scanning calorimetry (DSC) and complementary structural assays are widely used to evaluate protein and peptide-based haircare actives. Still, they are applied late in new ingredient development and require significant resources. A predictive, high-throughput strategy for early-stage screening of candidate materials for selective hair keratin binding remains needed. Additionally, identifying the specific keratin regions targeted by these actives can strengthen mechanistic understanding and guide rational product design.

Methods:
We present a high-throughput screening platform for assessing selective binding of proteins, peptides, and hydrolysates to human hair keratins. Fluorescently labelled materials are incubated in 96-well plates coated with defined keratin peptide fragments representing key structural domains. After controlled wash steps, designed to mimic pre-damaged, post-damaged or healthy hair, retained fluorescence is quantified using a plate reader to determine relative binding affinity and selectivity. Differential wash conditions are applied to explore potential interaction mechanisms, including covalent and electrostatic contributions.

Results:
Distinct binding profiles were observed across the tested materials, including selective affinity for regions of Keratin 32 and Keratin 82, which are abundant in the hair cuticle. Wash-dependent differences suggested multiple interaction modes, including disulphide-mediated and charge-driven associations.

Conclusion:
This scalable, cost-effective platform enables rapid, function-led prioritisation of protein and peptide actives, supporting precision-driven haircare development and accelerating innovation from discovery to formulation.