Determination of fentanyl and 19 derivatives in hair: Application to an Italian population.

Nowadays fentanyl and its analogs represent the most numerous group among synthetic opioid and, due to their higher potency in comparison to traditionl opioids, the main cause of the critical increase of fatal intoxications opioids-intake related in the USA. We developed an LC-MS/MS method for the detection and quantification of fentanyl and its analogs in hair, then applied to 117 real samples, 97 collected from drugs users and 20 from postmortem cases of drugs addicts. The ionization and MRM parameters have been optimized for 27 molecules: 20 reached the acceptance criteria for identification and quantification. LODs and LOQs of 0.2 and 0.5 pg/mg, respectively, were reached for most of the substances, except for five compounds for which were set at 0.5 and 1.0 pg/mg. 2 out of the 97 samples collected from drug users tested positive; one for carfentanil, butyryl fentanyl, THFF and ocfentanil; the other one for 3-methyl norfentanyl. 2 out of the 20 postmortem samples show positive results: one only for fentanyl, the other for furanyl fentanyl, acetyl fentanyl, methoxyacetyl fentanyl, methoxyacetyl norfentanyl, ocfentanil and 4-ANPP. Despite the relatively small number of samples, the results suggest that the method should be included in routine hair analyses for monitoring the new synthetic opioids potential intake by drug users.