Detection of stimulants in hair by laser microscopy.

In order to detect methamphetamine, a common stimulant, laser microscopy and immuno-histochemical staining, which uses anti-methamphetamine labeled with colloidal gold, were employed. The intensity of reflection of colloidal gold at a 488- and 514-nm line of Ar laser was measured with a laser microscope equipped with a computerized image processing system. Microtomed hair samples from five drug users who died from methamphetamine intoxication were used. The drug distribution in the hair was quite different in these five cases, but the levels of drug concentration in two different hair samples from the same abuser were correlated. The results from two hair samples with roots showed a correlation between drug concentration in hair roots and plasma samples. The proposed method needs no melanin bleaching and is simple and sensitive enough to estimate the drug concentration using only a segment of hair.