Barbie drug identification: Not a child's play

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.