Barbie drug identification: Not a child's play

Abstract

Various samples—including two vials with a pharmaceutical appearance—were submitted to the laboratory for identification. The aim of this work was to describe the unique characteristics observed during the analysis of the powder contained in the vial. Samples were submitted to HPLC-DAD, UHPLC-TOF-MS, and/or UPLC-MS–MS analysis. The majority of the samples were easily identified as standard drugs of abuse. The main difficulty lay in identifying the powder in the vials. No match was found in the library through HPLC-DAD analysis. Fortunately, the vials were labeled as “Melanotan II”, although the UV spectrum was not available. Mass spectrometric analysis of melanotan II was challenging, as it is a small peptide with a molecular weight of 1024 Da, which is significantly heavier than classical drugs that the laboratory usually handles. As a result, mass spectrometer's parameters can be limited to detect masses up to 1000 Da. Additionally, melanotan II is multi-charged which is also unusual for compounds typically targeted in our daily work. Finally, the reference standard allowed us to confirm the identification with both instruments, and determine the purity of 30%. Melanotan II is not approved on the market due to safety concerns. It is used illegally mainly for tanning, explaining its nickname “Barbie drug”. To conclude, analysis of melanotan II was challenging as it is heavy and doubly charged. Moreover, its UV spectrum was initially not available in the literature. The difficulties faced by forensic scientists in detecting this drug may explain its popularity on the illicit market.