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08:36
Generation of Integration-free Human Induced Pluripotent Stem Cells Using Hair-derived Keratinocytes
Published on: August 20, 2015
Reduction-induced surface modification of human hair
Yash K Kamath1, Sigrid B Ruetsch
1TRI/Princeton, Princeton, NJ 08542, USA.
Journal of Cosmetic Science
|March 10, 2010
Summary
This study introduces microfluorometry to measure lipid removal from human hair cuticles during chemical treatments. This technique quantifies hair surface changes from hydrophobic to hydrophilic, aiding in hair care product development.
Area of Science:
- Hair science
- Surface chemistry
- Analytical chemistry
Background:
- Human hair cuticle lipids are crucial for hair health and appearance.
- Chemical treatments like oxidation and reduction alter hair surface properties.
- Understanding these alterations is key for developing effective hair care products.
Purpose of the Study:
- To develop and validate a microfluorometric method for quantifying lipid removal (delipidation) from the human hair cuticle.
- To characterize surface chemistry changes induced by light exposure and chemical treatments.
- To assess the potential for 'relipidation' using cationic conditioners.
Main Methods:
- Microfluorometry using Rhodamine B to tag and quantify changes in hair cuticle surface chemistry.
- Microfluorometric scanning to detect negative charges generated on the cuticle.
- Wilhelmy technique for single-fiber wettability scanning to assess surface hydrophilicity/hydrophobicity.
Main Results:
- Microfluorometry successfully quantifies lipid removal and acidification of the hair cuticle during oxidation (bleaching) and reduction.
- Detected changes in surface chemistry from hydrophobic to hydrophilic.
- Demonstrated the binding of cationic conditioners to negatively charged sites on the cuticle, indicating successful 'relipidation'.
Conclusions:
- Microfluorometry is a reliable method for characterizing hair cuticle delipidation and surface changes.
- Chemical treatments significantly alter hair surface chemistry, which can be reversed or modified by conditioning treatments.
- The findings provide insights into hair damage and repair mechanisms, relevant for cosmetic science.
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