Ultra-Sensitive Cocaine Detection

Forensic science student Sonica Devi has found minute traces of cocaine at a number of public phone boxes in the city of Derby – thanks to a new development in forensic analysis.

The development of an ultra sensitive Gas Chromatographic technique enabled the University of Derby science team to detect cocaine at picogram levels – one million millionth of a gram from forensic swabs.

Gas Chromatography linked to a mass spectrometer (GCMS) is an established technique for separating complex mixtures of compounds and detecting them down to very low amounts.

Sonica, a final year student at the University of Derby, developed this novel technique to help identify minute traces of cocaine at all six phone boxes she tested. A standard method would have easily missed the presence of this drug at these low levels.

For the study, sterile swabs were used to collect samples from different areas of each phone box. Samples were taken using a variety of swabs and were taken back to the University’s Kedleston Road laboratories for analysis and each of the swabs were placed in tubes containing a solvent called Dichloromethane (DCM). The solvent dissolves the cocaine and allows it to enter the Gas Chromatograph.

After separating the cocaine from other materials lifted by the swabs the mass spectrometer detector provides a means to detect the cocaine – using the method developed by Sonica this was performed with extremely high sensitivity.