Analysis of morphine by RIA and HPLC in fingernail clippings obtained from heroin users

Heroin is abused around the world and is frequently reported as the cause of death in overdose cases. Analysis of morphine in hair has been used in the past in forensic toxicology to study the addiction history of heroin addicts. The purpose of the present study was to evaluate the usefulness of the nail as an analytical specimen in the identification and quantification of morphine in fingernail clippings of known heroin users. Fingernail clippings were obtained from 26 consenting patients of the Glasgow Drug Problem Service. At the time of sampling, the participants provided answers to a questionnaire regarding their drug use patterns. Samples were decontaminated by sonication in SDS, deionized water and methanol, and the methanolic washes were screened for analyte presence. The washed nail clippings were then hydrolyzed and extracted. RIA was used for the screening and HPLC for the confirmation of morphine. Positive RIA results were obtained with nail clippings from 25 of the 26 heroin users. The levels ranged from 0.06 to 4.69 ng/mg with a mean morphine concentration of 1.67 ng/mg. HPLC results were positive for 22 of the 26 nail samples. The mean morphine level by HPLC was 2.11 ng/mg with a range from 0.14 to 6.90 ng/mg. Based on these results, we suggest that nails have the potential of becoming a powerful alternative to hair for the detection of past heroin use in forensic cases.