DETERMINATION OF LSD IN BLOOD BY CAPILLARY ELECTROPHORESIS WITH LASER-INDUCED FLUORESCENCE DETECTION

Capillary electrophoresis (CE) with HeCd laser-induced fluorescence (L IF) detection and its application in forensic toxicology is demonstrat ed by the determination of D-lysergic acid diethylamide (LSD) in blood . Following precipitation of proteins, washing of the evaporated super natant and extraction, the residue was reconstituted in methanol and i njected electrokinetically (10 s, 10 kV). The total analysis time for quantification of LSD was 8 min using a citrate-methanol buffer, pH 4. 0. With this buffer system it is possible to separate LSD, nor-LSD, is o-LSD and iso-nor-LSD. Using a specific sample preparation, electrokin etic injection, extended light path (bubble cell) capillaries and espe cially LIF detection (lambda(ex) 325 nm, lambda(em) 435 nm), a limit o f detection of 0.1-0.2 ng LSD per ml blood could be obtained. The limi t of quantitation was about 0.4-0.5 ng/ml. The quantitative evaluation for LSD was carried out using methylergometrine as internal standard. The precision expressed as coefficient of variation (C.V.) and accura cy of the method were <20% and 86-110%, respectively. The application of the method to human blood samples from two forensic cases and a com parison with radioimmunoassay demonstrated that the results were consi stent.