NCJ Number
162861
Journal
Journal of Forensic Sciences Volume: 41 Issue: 1 Dated: (January 1996) Pages: 121-125
Date Published
1996
Length
5 pages
Annotation
This paper presents an experimental approach of histology of the human hair fiber in dyeing and diffusion phenomena and its contribution to the interpretation of hair analysis results for drug abuse.
Abstract
Rhodamine B was applied to human hair fibers from either aqueous solution or methanol/ethanol solvent. The experiments were performed on natural hair of different ethnic groups as well as on extensively bleached hair strands. The reagent entered the unmodified fibers at the scale edges between the cuticle cells. At the beginning of the diffusion process intercellular diffusion was the preferred route predominantly along the nonkeratinous regions of the cell membrane complex and intermacrofibrillar cement. Penetration into the high-sulfur regions of the fiber occurred as dyeing in aqueous solution proceeded and resulted in evenly stained cross-sections. Determination of the amount of dye taken up by the fibers by spectrophotometric analysis demonstrated that samples' diffusion generally increased by time and temperature, and also depended on the morphology of the hair sample. The authors considered it difficult to gain reliable interpretation of drug monitoring of distal hair segments far away from the scalp or hair samples with cosmetic treatment. Figures, tables, references