Determination of melanin in human hair by photoacoustic spectroscopy.
A highly sensitive photoacoustic spectroscopy for the determination of melanin in human hair has been developed. Both synthetic melanin and human hair were treated with 50% sulfuric acid. The melanin suspension was passed through the membrane filter to collect melanin, and the filter was transferred into a homemade photoacoustic cell, followed by measurement of the photoacoustic signals produced by 10 mW He-Ne laser beam. The good correlation between the method described in this paper and absorption spectrophotometry was confirmed quantitatively. The linearity observed between the photoacoustic signal and the weight of samples was in the range of 0.1-20 micrograms for synthetic melanin and 10-800 micrograms for human hair, with detection limits of 5 ng and 0.38 microgram, respectively.
Watanabe
T
T
Department of Analytical Chemistry, Faculty of Pharmaceutical Science, Hoshi University, Tokyo, Japan. watanabe@hoshi.ac.jp
Tamura
A
A
Yoshimura
Y
Y
Nakazawa
H
H
D004578:Electron Spin Resonance Spectroscopy; D005609:Free Radicals / Q000378:metabolism; D006197:Hair / Q000737:chemistry*; D006801:Humans; D008543:Melanins / Q000032:analysis*; D013057:Spectrum Analysis / Q000379:methods*; D013464:Sulfuric Acids / Q000378:metabolism
D005609:Free Radicals; D008543:Melanins; D013464:Sulfuric Acids; C033158:sulfuric acid