A growing number of incidents involving illicit sale of experimental peptide and protein drugs has prompted Belgian researchers to develop a rapid screening test.
The team - from Belgium's Scientific Institute of Public Health - looked at the potential of an analytical technique known as liquid chromatography-tandem mass spectrometry (LC–MS/MS) for the detection of counterfeit and illegal injectable peptides.
Examples of experimental peptide and protein drugs intercepted by regulatory and customs officials in Europe include growth hormone releasing peptides such as sermorelin and ipamorelin - misused by bodybuilders and as an anti-aging treatment - obesity candidates such as AOD9604 and anticancer drug epitalon, amongst others.
The unlicensed drugs are often supplied over the Internet and are routinely intercepted in small shipments by enforcement agencies. They can lead to "severe health threats, as has been demonstrated by numerous case reports," the researchers report in the journal Talanta.
"At present pharmacopoeias in Europe and the US do not provide any guidelines for a positive identification of these substances," they write.
Borrowing from techniques used to detect doping in sport, the scientists used LC-MS/MS as an initial screen followed by ultra-high performance liquid chromatography with diode array detection (UHPLC-DAD) to confirm the preliminary finding.
The approach allowed some 25 different peptides could be identified within 30 minutes and in some cases the researchers were able to determine the amount of peptide present without resorting to experiments involving labelled peptide standards, which are expensive reagents.
They tested 65 samples seized by Belgium's Federal Agency for Medicines and Health Products (FAMHP) between 2009 and found one or more of the peptides were present in 33 of them.
"It could be envisaged that this method could be used for routine analysis of suspected illegal peptide biopharmaceuticals, without the purchase of expensive labelled internal standards," they conclude.