Comparison of methods to develop fingerprints on papers impregnated with AB-PINACA and AB-FUBINACA

Although there have been significant advances in fingerprinting techniques, studies on how these techniques affect other criminal evidence are limited. Synthetic cannabinoids (SC), which are illegal substances frequently encountered in crime scenes and are widely used worldwide, are available in various forms in the market (pill, powder, liquid, and herbal product). These synthetic cannabinoid substances have recently been introduced to places such as prisons and rehabilitation centers, primarily via an infused piece of paper. The first seizure of the paper-impregnated form of AB-PINACA and AB-FUBINACA in Turkey was observed in 2014. This study investigates the effects of fingerprint development methods on the concentrations of these SCs impregnated on paper. Therefore, eccrine and sebaceous fingerprints of volunteers were imprinted on the papers before and after they were impregnated with AB-PINACA and AB-FUBINACA. Six different fingerprint development methods were applied. Fingerprint development methods were later checked in 384 fingerprints. AB-PINACA and AB-FUBINACA infused on papers were extracted by the liquid-extraction method, and concentrations were analyzed via LC-MS/MS. After applying Thermanin, 1,2-indandione, iodine vapor, DFO, and 5-MTN fingerprint development methods, the concentration levels of AB-FUBINACA were 26.25, 19.60, 21.43, 17.76, and 17.77 ng/cm² , while the concentration levels of AB-PINACA were 1.1, 0.98, 1.31, 1.28, and 1.22 ng/cm² , respectively. Finally, although the best fingerprint visualization was obtained on papers that were applied the Ninhydrin method, the method failed to detect SCs on papers.