Laboratoire National de Santé, Division de Toxicologie
* Laboratoire d'Analyse des Matériaux, CRP-CU
Centre Universitaire de Luxembourg, 162A, avenue de la Faïencerie, L-1511 Luxembourg

In the last few years Time-of-Flight Secondary Ion Mass Spectrometry (ToF-SIMS), one of the most sensitive analytical techniques in surface science, has also become a powerful tool for analysing biomolecules adsorbed on a noble metal. In the present work, the performance of ToF-SIMS for the detection of several drugs (cocaine, morphine, scopolamine, LSD and buprenorphine) in serum and urine after liquid-liquid extraction was evaluated. The extraction procedures and the sample preparation were investigated in order to establish an analytical protocol. Comparative investigations of the nature of the metal substrate, used to absorb the extracts, show for the first time an optimum emission of secondary ions obtained from gold substrates.

In a first step, buprenorphine, which is rather difficult to detect in routine clinical and forensic analytical toxicology was selected for in-depth investigation. In a first approach extraction yield in urine was found to be 40 - 50%. The limit of detection (LOD) has been determined to be 1 ng/ml and the standard deviation (SD) was 0.05. This assay was used for comparison of ToF-SIMS and LC/MS results in the case of several fatal buprenorphine intoxications.