Evaluation of the presence of drugs of abuse in tap waters.

A total of seventy samples of drinking water were tested for non-controlled and illicit drugs. Of these, 43 were from Spanish cities, 15 from seven other European countries, three from Japan and nine from seven different Latin American countries. The most frequently detected compounds were caffeine, nicotine, cotinine, cocaine and its metabolite benzoylecgonine, methadone and its metabolite EDDP. The mean concentrations of non-controlled drugs were: for caffeine 50 and 19 ng L(-1), in Spanish and worldwide drinking water respectively and for nicotine 13 and 19 ng L(-1). Illicit drugs were sparsely present and usually at ultratrace level (<1 ng L(-1)). For example, cocaine has mean values of 0.4 (Spain) and 0.3 ng L(-1) (worldwide), whereas for benzoylecgonine, these mean values were 0.4 and 1.8 ng L(-1), respectively. Higher concentrations of benzoylecgonine were found in Latin American samples (up to 15 ng L(-1)). No opiates were identified in any sample but the presence of methadone and EDDP was frequently detected. Total mean values for EDDP were 0.4 ng L(-1) (Spain) and 0.3 ng L(-1) (worldwide). Very few samples tested positive for amphetamines, in line with the reactivity of chlorine with these compounds. No cannabinoids, LSD, ketamine, fentanyl and PCP were detected.

State-of-the-art of the hyphenation of capillary electrochromatography with mass spectrometry.

The high separation efficiency and loading capacity of capillary electrochromatography (CEC) make it an attractive separation mode for coupling with mass spectrometry (MS), which has the ability to unambiguously identify analytes with high selectivity and sensitivity. We present an overview of recent advances on both instrumentation and separation columns employed in CEC-MS systems. In particular, the main characteristics of the stationary phases, as well as the configurations of the column outlet that are related with the coupling arrangements of the MS ionization sources, are reported. At present, packed columns and conventional electrospray ionization (ESI) sources are mainly employed in CEC-MS. Nevertheless, the use of monolithic capillary columns and nanoelectrospray sources has the potential for wide acceptance in the next future. Moreover, the main features of several mass analyzers including ion trap, quadrupole, time-of-flight, magnetic sector, and Fourier transform-ion cyclotron resonance are examined. Finally, current applications of this technology, mainly in the pharmaceutical field and proteomics, are reviewed.

Optimization of a clean-up procedure for the determination of heterocyclic aromatic amines in urine by field-amplified sample injection-capillary electrophoresis-mass spectrometry.

Heterocyclic amines (HAs), generated when proteinaceous food is cooked, are of special interest since they can be carcinogenic for humans. In this paper, the optimization of a clean-up procedure for the isolation and preconcentration of 15 heterocyclic amines in urine samples is described. The method proposed combines liquid extraction on a solid support of diatomaceous earth with solid-phase extraction in cartridges. Tests were performed on several cartridges containing graphitic carbon or mixed phases, i.e., combining reversed-phase and cation-exchange mechanism, and the best results were obtained with Oasis MCX. The optimized purification method was applied to the quantification of heterocyclic amines in hydrolyzed spiked human urine. The method was carried out by capillary electrophoresis (CE) coupled to mass spectrometry (MS) and applying field-amplified sample injection (FASI) as in-line preconcentration procedure. We obtained detection limits down to 0.3 ng/ml of urine and errors lower than 17%.

Determination of heterocyclic aromatic amines by capillary electrophoresis coupled to mass spectrometry using in-line preconcentration.

This paper shows the potentiality of capillary electrophoresis (CE) coupled to mass spectrometry (MS) for the analysis of heterocyclic aromatic amines obtaining good results in terms of sensitivity and precision. These compounds have a special interest since they can be carcinogenic for humans. The optimization of a CE-MS method was performed and the best conditions were obtained using a 16 mM formic acid/ammonium formate solution at pH 4.5 with 60% methanol as running electrolyte. For CE-MS coupling, a sheath liquid methanol/20 mM formic acid (75/25) solution at a flow rate of 3 microL/min and hydrodynamic injection of methanol mixtures for 10 s were used. Detection limits ranging from 18 ng/g to 360 ng/g and precisions up to 1.4% and 12% for migration time and concentration, respectively, were obtained. In order to improve sensitivity, field-amplified sample injection was applied as an in-line preconcentration method. Methanol/5 mM formic acid (50/50) as a sample solvent, 3 s hydrodynamic injection (0.5 psi) of a methanol plug, and 25 s of electrokinetic injection (10 kV) of the sample were found to be the optimum conditions. Detection limits up to 25 times lower and similar precisions than those reported for hydrodynamic injection were obtained.