Abstract: Sample solution containing amphetamines was mixed with a stream of 0.2 M carbonate buffer (pH 9) at 0.9 mL min-1 in a flow injection analysis system. The drugs were derivatized after the stream was mixed with a stream of 50 µM-9-fluorenylmethyl chloroformate in acetonitrile at 0.5 mL min-1. The resulting derivatives were determined after pre-concentration. on a column (1.3 cm x 2 mm) of Nucleosil C18 (40 to 63 µm); an analytical column (20 cm x 4 mm) of Nucleosil C18 (5 µm) was used, with UV detection. The mobile phase (1.5 mL min-1) was aqueous 58% acetonitrile. Calibration graphs were rectilinear from 0.02 to 0.1 µM of amphetamine, methylamphetamine, ephedrine and phenylpropanolamine.

Abstract: Two solution were prepared for filling the two drive syringes of the stopped-flow module. One contained 10 µL of urine and an appropriate volume of the fluorescein-labelled analyte in buffer in a final volume of 0.5 mL. The other contained an appropriate volume of the antibody in 0.5 mL of buffer. Portions (40 µL) of the two solution were transferred to the mixing chamber at 20 ml/s. The time course of the fluorescence intensity was measured in the two emission channels at 550 nm (excitation at 494 nm). The stopped-flow module was computer-controlled and the initial reaction rate was determined in 5-10 s. The procedure was exemplified by the determination of amphetamine and of the metabolites benzoylecgonine and 11-nor-Δ8-tetrahydrocannabinol-9-carboxylic acid. Calibration graphs for these three were 20-300, 15-300 and 10^-400 µg/l respectively, with detection limits of 7, 5 and 3 µL/l, 3-12 times lower than by conventional fluorescence polarization immunoassay. The new method was also more precise (RSD of 1.4-3.6%, vs. 2.2-7.4%) and recovery was close to 100%. The correlation between the two methods was excellent (r > 0.99).

Abstract: A fast anal. approach for the simultaneous quant. screening for illicit drugs in serum and urine without tedious chromatography separation steps was developed by combining solid phase extraction (SPE) followed by flow injection analysis (FIA) with ion spray-ionization and tandem mass spectrometry (MS-MS) detection using a PE Sciex API 300 triple-quadrupole MS. MS-MS anal. was performed by sequentially isolating the precursor ions of the analytes and their deuterated standards with subsequent fragmentation and monitoring of one fragment ion for each substance. A multiple-reaction monitoring experiment was set up for morphine (MO), codeine (COD), amphetamine (AMP), benzoylecgonine (BZE), and their deuterated analogs. For method evaluation, serum samples spiked with 2-1000 ng of each drug and deuterated standards were extd. by mixed-mode SPE, redissolved in MeCN-NH4OAc-buffer, and directly injected by flow injection into the ion spray source. The specificity of this new method was demonstrated by testing compounds with similar chemical structure for interferences from the analytes of interest (e.g., hydromorphone, morphine glucuronide, and 6-monoacetylmorphine with MO; dihydrocodeine and hydrocodone with COD; cocaine [COC] and ecgonine methylester with BZE; methamphetamine with AMP). The possibility of interferences of such compounds with the FIA-ion spray-MS-MS screening method is discussed. Spiked serum samples and serum and urine samples from drug addicts and victims of drug abuse were analyzed with FIA-MS-MS and, after derivatization, with gas chromatography-mass spectrometry (GC-MS). Comparable quant. results were obtained with both methods; no interferences with metabolites or other compounds were found. The FIA-ionspray-MS-MS method is a fast, quant., sensitive, and highly specific alternative method to drug-screening by immunoassays, high-performance liquid chromatography, and GC-MS. It can be used for the simultaneous detection of different drugs and metabolites such as opiates, COC, AMP derivatives, and many other drugs.