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An original analytical method has been developed for the determination of the antioxidants trans-resveratrol (t-RSV) and cis-resveratrol (c-RSV) and of melatonin (MLT) in red and white wine. The method is based on HPLC coupled to fluorescence detection. Separation was obtained by using a RP column (C8, 150 mm x 4.6 mm id, 5 mum) and a mobile phase composed of 79% aqueous phosphate buffer at pH 3.0 and 21% ACN. Fluorescence intensity was monitored at lambda = 386 nm while exciting at lambda = 298 nm, mirtazapine was used as the internal standard. A careful pretreatment of wine samples was developed, using SPE with C18 cartridges (100 mg, 1 mL). The calibration curves were linear over the following concentration ranges: 0.03-5.00 ng/mL for MLT, 3-500 ng/mL for t-RSV and 1-150 ng/mL for c-RSV. The LOD values were 0.01 ng/mL for MLT, 1 ng/mL for t-RSV and 0.3 ng/mL for c-RSV. Precision data, as well as extraction yield and sample purification results, were satisfactory. Thus, the method seems to be suitable for the analysis of MLT and resveratrol isomers in wine samples. Moreover, wine total polyphenol content and antioxidant activity were evaluated.

Benzodiazepines are currently among the most frequently prescribed drugs all over the world. They act as anxiolytics, sedatives, hypnotics, amnesics, antiepileptics and muscle relaxants. Despite their common chemical scaffold, these drugs differ in their pharmacokinetic and metabolic properties. In particular, they are biotransformed by different cytochrome P450 isoforms and also by different UDP-glucuronosyltransferase subtypes. The most important studies on the metabolic characteristics of several 1,4-benzodiazepines, carried out from 1998 onwards, are reported and briefly discussed in this review. Moreover, the analytical methods related to these studies are also described and commented upon and their most important characteristics are highlighted. Most methods are based on liquid chromatography, which provides wide applicability and good analytical performance granting high precision, accuracy and feasibility. Mass spectrometry is gaining widespread acceptance, particularly if the matrix is very complex and variable, such as human or animal blood. However, spectrophotometric detection is still used for this purpose and can grant sufficient selectivity and sensitivity when coupled to suitable sample pre-treatment procedures. A monograph is included for each of the following benzodiazepines: alprazolam, bromazepam, brotizolam, clotiazepam, diazepam, etizolam, flunitrazepam, lorazepam, midazolam, oxazepam and triazolam.

The strong antioxidant activity of melatonin is well known and it is important to investigate its presence and levels in different foodstuffs, for the purpose of evaluating their nutraceutical properties. As a contribution towards this goal, an original analytical method has been developed for the simultaneous determination of melatonin and other indolic and phenolic antioxidants (including trans- and cis-resveratrol, ferulic acid, tryptophan, serotonin and 5-hydroxyindoleacetic acid) in grape-related foodstuffs and beverages: namely grape, grape juice, must, wine and grappa (Italian pomace brandy). These foodstuffs represent an important part of the diet, both traditionally and in recent times, especially in Mediterranean countries and could be (at least in part) responsible for the beneficial effects involved in the 'French paradox'. The analytical method is based on high-performance liquid chromatography coupled to fluorescence detection, exploiting the native fluorescence of the analytes. A C8 column was used as the stationary phase, while the mobile phase was composed of acidic phosphate buffer and acetonitrile; fluorescence intensity was monitored at λ=386nm while exciting at λ=298nm. The sample pretreatment was carried out by a fast and reliable microextraction by packed sorbent (MEPS) procedure. After validation, the method was applied to the analysis of melatonin and other antioxidants in food and beverages derived from grape, with very good results being obtained. Thus, this methodology may represent a promising tool for the evaluation of the antioxidant properties of nutraceuticals and functional foods.

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The development of new "atypical" antipsychotic agents, which are safer than classical neuroleptics and also active against the negative symptoms and neurocognitive deficits caused by the illness, has produced a significant advancement in the treatment of schizophrenia. The atypical (or "second generation") antipsychotics have several therapeutical properties in common, however they can significantly differ with regard to clinical potency and side effects. The main features regarding pharmacodynamics, pharmacokinetics and pharmacological interactions of the most important atypical antipsychotics, namely clozapine, olanzapine, quetiapine and risperidone, are treated herein. Several analytical methods available for the therapeutic drug monitoring of these drugs are also presented, as well as the novel formulations, which can notably improve the therapy of schizophrenia. Other very recent atypical agents, such as ziprasidone, aripiprazole, iloperidone, sertindole and zotepine will also be briefly described.

Stationary phases for capillary electrochromatography with a longitudinal gradient of functionalities have been prepared via photoinitiated grafting of polymer chains onto the pore surface of a porous polymer monolith. In order to achieve the desired retention and electroosmotic flow, the hydrophobic poly(butyl methacrylate-co-ethylene dimethacrylate) monolith with optimized porous properties was grafted with a layer of ionizable polymer, poly(2-acrylamido-2-methyl-1-propanesulfonic acid). A moving shutter and a neutral density filter were used to control the dose of UV light received at different locations along the monolith in order to create the longitudinal gradient of functionalities. Formation of the desired gradients was confirmed using electron probe microanalysis of different locations along the column. The preparation technique significantly affects performance in the CEC mode as demonstrated on the separations of a model mixture using columns both with homogeneous distribution of grafts and with a gradient of functionality. Columns grafted with the gradient of functionalities were found superior to those functionalized uniformly. A comparison of the performance of the gradient column with another containing evenly distributed functionalities showed the performance benefits of the "gradient" column.