Toward the Rational Design of Sustainable Hair Dyes Using Cheminformatics Approaches: Step 1. Database Development and Analysis

Abstract

Herein, we report on the initial step of the design process of new hair dyes with the desired properties. The first step is dedicated to the development of the largest, publicly available database of hair dye substances (containing temporary and semipermanent hair dyes as well as permanent hair dye precursors) used in commercial hair dye formulations. The database was utilized to perform a cheminformatics study assessing the computed physicochemical properties of the different hair dye substances, especially within each cluster of structurally similar dyes. The various substances could be differentiated based on their average molecular weight, hydrophobicity, topological polar surface area, and number of hydrogen bond acceptors, with some overlap also observed. In particular, we found that dyes such as C.I. Basic Orange 1 and 2 were clustered among the precursors, suggesting that their diffusion behavior is similar to that of permanent hair dye precursors. We anticipate taking advantage of this interesting knowledge in the second design phase of our investigation. As a step in that direction, we used QSAR models and noted that 65% of the substances were predicted to be mutagenic (22 with confidence thresholds >90%), whereas 79% were predicted to be skin sensitizers (37 with confidence thresholds >90%). We discuss the relevance of these preliminary calculations in view of literature-extracted experimental data.

Coloration, Hair

“…Temporary dyes are ionic in nature, while semipermanent dyes are either ionic or nonionic. Examples of temporary and semipermanent dyes can be found in Hair Dye Substance Database recently developed by Williams and co-workers [14], which is available for download at https://figshare.com/articles/Hair_Dye_ Substance_Database_HDSD_/5505856. Each of the dye classes, with respect to their diffusion into hair after dyeing, is schematically represented in Fig.…”

“…Some examples of exceptions for couplers are naphthols and pyridines [1]. Examples of other precursors can be found in the Hair Dye Substance Database recently developed by Williams and co-workers [14], which is available for download at https:// figshare.com/articles/Hair_Dye_Substance_Data base_HDSD_/5505856. Couplers, which are essentially colorless, are known as color modifiers, because they play a role in determining the final color achieved [1,3,5,30].…”

Therapeutics of premature hair graying: A long journey ahead

“…A recent study in the United States of America has come up with database that is efficient in performing “chemiinformatics” using computed physicochemical properties of different hair dye substances such as hydrophobicity, number of hydrogen bond acceptors, and topography. This information can also be used to check the mutagenicity, skin sensitization future for synthesis of “allergy free dyes” …”

Analysis of keratin films as screening tools for predicting the efficacy of potential hair dyes

“…In the current study, CI Acid Orange 7, a non‐oxidative hair dye, was used to investigate the concentration, deposition and spatial distribution of dye in opaque and translucent human hair keratin films using UV‐Vis and TOF‐SIMS. Scanning electron microscopy (SEM) was used to examine the morphology of both films relative to untreated and bleached human hair keratin fibres.…”