Different Localizations of Drugs Simultaneously Administered in a Strand of Hair by Micro-Segmental Analysis
October 2017
in “
Drug testing and analysis
”
TLDR Drugs localize differently in hair strands based on their properties.
The study investigated the distribution of 7 compounds in hair strands using micro-segmental analysis to determine the day of drug intake. Hair samples were collected from subjects 33.1−229.4 days after they were administered 4 pharmaceutical products containing 10 drugs within 32 hours. Drugs and metabolites were extracted from 0.4-mm hair segments and quantified using liquid chromatography–tandem mass spectrometry. Acidic and neutral compounds were detected in low amounts, while other drugs like epinastine, fexofenadine, dihydrocodeine, and chlorpheniramine were localized to 2 regions within a hair strand. Methylephedrine and its metabolite, ephedrine, were localized to only one region. The study found minimal differences in drug concentration curves among 20 hair strands from different subjects and head regions, suggesting that drug uptake into hair can vary based on drug properties. This method could help identify the exact day of drug intake and understand drug uptake mechanisms in hair.
