SOLVENT-FREE SAMPLE PREPARATION BY HEADSPACE SOLID-PHASE MICROEXTRACTION APPLIED TO THE TRACING OF N-BUTYL NITRITE ABUSE

The most common alkyl nitrites encountered in forensic toxicology are iso-butyl, n-butyl and iso-pentyl(amyl) nitrites. All have become popu lar as an aphrodisiac, especially among the homosexual population. Alk yl nitrites are a volatile and unstable group of compounds, which hydr olyse in aqueous matrices to the alcohol and nitrite ion. Here we desc ribe a fast, clean and sensitive procedure for the detection of hydrol ysed n-butyl nitrite in whole human blood using a new, solvent-free sa mpling technique, the headspace solid-phase microextraction (HSPME), c ombined with GC/FID analysis. Sample preparation was investigated usin g tow different stationary phases (100 mu m polydimethylsiloxane and 8 5 mu m polyacrylate), coating a fused silica fibre. The effect of diff erent sampling times at fixed temperatures was also studied. Our resul ts demonstrate that the HSPME/GC/FID procedure allows tracing of n-but yl nitrite abuse and detects hydrolysed n-butyl nitrite, i.e. released n-butanol, in whole blood at the 1 ng/mL level.