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Quaternary nitrogen muscle relaxants pancuronium, rocuronium, vecuronium, gallamine, suxamethonium, mivacurium, and atracurium and its metabolites were extracted from whole blood and other biological fluids and tissues by using a solid-phase extraction procedure. The extracts were examined by using high-performance liquid chromatography-electrospray ionization mass spectrometry (LC-ESI-MS). The drugs were separated on a ODS column in a gradient of ammonium acetate buffer (pH 5.0) and acetonitrile. Full-scan mass spectra of the compounds showed molecular ions, and MS-MS spectra showed fragments typical of the particular compounds. LC-ESI-MS allowed an unequivocal differentiation of all muscle relaxants involved. The method was applied in a case of rocuronium and suxamethonium administration in a Caesarian section and in a case of intoxication by pancuronium injection. In both cases, the administered drugs could be detected and identified in the supplied samples.

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A single-column solid-phase extraction procedure was developed for the screening of acidic, neutral, and basic drugs from plasma. The recoveries of all 25 tested drugs exceeded 82%. After the plasma had been diluted with phosphate buffer (pH 6.0), the drugs were extracted using a single Bond Elut Certify column. The acidic and most of the neutral drugs were eluted by acetone/chloroform (1:1) and the basic drugs were eluted by 2% ammoniated ethyl acetate. Some neutral drugs appeared in both fractions. The two fractions were collected separately and evaporated until approximately 100 μL of solvent remained in the tube. Both fractions were analyzed separately on a gas chromatograph equipped with a wide-bore capillary column and a flame ionization detector. The procedure could also be used for urine samples.

In systematic toxicological analyses (STA), analytical methods are needed with a high Identification Power. The mean list length (MLL) approach, which is an improved and extended version of the Identification Power concept, provides an objective tool for the evaluation and optimum choice of analytical methods for STA. The MLL approach is elucidated and applied to the screening for basic drugs by thin layer chromatography (TLC) and gas-liquid chromatography (GLC). Its usefulness for TLC and GLC systems for the identification of these basic drugs has been evaluated for both single systems and combinations of systems. The MLL approach is also substance directed and can be applied to computerized data searches and substance identification. The method is applicable for single analytical systems and combinations of systems. Mixtures of substances can also be handled.

Volunteer staff from a Neonatal Intensive Care Unit (NICU) were presented with sets of anonymised physiological data recorded over approximately 45 minute periods from former patients. Staff were asked to select medical/nursing actions appropriate for each of the patients whose data were displayed. Data were shown in one of three conditions (a) as multiple line graphs similar to those commonly shown on the ward, or as textual descriptions generated by (b) expert medical/nursing staff or (c) computerised natural language generation (NLG). An overall advantage was found for the human generated text, but NLG resulted in decisions that were at least as good as those for the graphical displays with which staff were familiar. It is suggested that NLG might offer a viable automated approach to removing noise and artefacts in real, complex and dynamic data sets, thereby reducing visual complexity and mental workload, and enhancing decision‐making particularly for inexperienced staff. Copyright © 2008 John Wiley & Sons, Ltd.

Direct enantiomeric separations of 17 chiral amidotetralins by means of high performance liquid chromatography were performed on stationary phases composed of tris(3,5-dimethylphenylcarbamate) derivatives of cellulose and amylose, coated on silica gel. The enantiomers of 15 out of 17 amidotetralins were resolved with a resolution of more than 1.5 by at least one of the chiral stationary phases. The stationary phases showed complementary results with regard to the separation of the amidotetralins, that is, pairs that did not separate on the cellulose-type column were well separated on the amylose-type column, and vice versa. There was no significant correlation between the chromatographic properties of the chiral stationary phases. o 1993 Wiley-Liss, Inc.KEY WORDS: cellulose, amylose, silica gel, high performance liquid chromatography, direct separationsHigh performance liquid chromatography (HPLC) has been the fastest developing chromatographic technique during the last two decades in the area of chiral applications. For direct separations with chiral HPLC, much work has been done with straight phase systems and water-free eluents. With these systems analyses from biological matrices can only be performed after a good sample pretreatment, since some commercially available stationary phases are easily ruined by small amounts of biological material (e.g., proteins).In 1980 Blaschke4 described the use of cellulose, starch, and cellulose acetate as chiral sorbents. Later, Okamoto et al. published promising results on stationary phases containing cellulose triesters coated on macroporous silica. These stationary phases belong to the general category of polysaccharide sorbents, and the formation of diastereoisomeric complexes involves hydrogen bonding, n-n complexes, and dipole interactions. Different cellulose derivatives were studied by Okamoto et aL6 They found that the dimethylphenyl-and dichlorophenyl-carbamates, substituted at the 3,4 or 3,5 positions, showed better chiral recognition for most enantiomers studied compared to the monosubstituted carbamates. The mobile phases used in combination with these columns were nonpolar, that is, hexane modified with an alcohol, for example, ethanol. Compounds separated successfully on these phases contain combinations of phenyl, carbonyl, nitro, cyano, sulfonyl, and hydroxyl groups. A commercially available cellulose derivative is tris(3,5-dimethylphenylcarbamate). In mixed with acetonitrile. At the moment, cellulose-based chiral stationary phases (CSPs) are commercially available for both reversed and straight phase modes, but the majority of these phases are still to be used with water-free eluents.In addition to cellulose-type columns, amylose-type stationary phases were developed.*910*" Cellulose and amylose differ only in the configuration on the 1-4 position of the D-glucose units being 1-4p-in the cellulose unit while it is 1-4a-in the amylose unit, as can be seen in Figure 1. This results in a different spatial arrangement between cellulose, being rigid and...

This paper describes a relatively simple and rapid analytical procedure capable to carry out systematic screening for 10 heavy metals, namely mercury, bismuth, antimony, copper, lead, tin, thallium, indium, cadmium and zinc. Differential pulse anodic stripping voltammetry was chosen because of its simplicity, speed, low cost, low detection limits, screening potential for a wide selection of metals and the combined qualitative and quantitative output. The method of identification is based on measuring peak potentials in 2 different types of electrolyte solution, using 2 different electrodes. Complexing agents are used to mask certain elements.