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One of the many attempts to stop the danger of tobacco smoking is the development of an anti-smoking vaccine using nicotine butyric acid (NBA) linked to a carrier protein to produce anti-nicotine antibodies. NBA is a chiral molecule and there is a need to obtain a high degree of enantiomeric purity. The aim of this work is to develop a novel method for the enantioseparation of NBA and the determination of trace amounts of enantiomeric impurity required by regulatory authorities. This was achieved successfully using high-performance capillary electrophoresis combined with label-free intrinsic imaging as new imaging technology. A 50 μm id fused-silica capillary was used with UV detection at λ(214 ) nm and label-free intrinsic imaging. The background electrolyte consisted of highly sulphated β-cyclodextrin 10% m/V as a chiral selector in 75 mM phosphoric acid-triethylamine at pH 7.0. Baseline separation and detection of 0.1% and possibly less of the unwanted impurity (R-enantiomer) were achieved. Also, the detection limits were calculated for both enantiomers. The use of label-free intrinsic imaging has improved the sensitivity, enabling us to detect trace amounts of enantiomeric impurities.

Photometric accuracy is determined by the difference between the measured absorbance and the established standard value. Most quantitation applications using UV-Vis would involve the measurement of the standards and samples of comparable concentrations in rapid succession on the same instrument. Photometric accuracy is critical for measurement; it compares the extinction coefficients between different instruments, for any photometric inaccuracy will lead to errors in quantitation. In Circular Dichroism (CD) measurements it is important and often a requirement to also monitor the absorbance of the sample. However, it is common to make separate measurements to determine the absorbance which is less accurate and time consuming. This study shows that the simultaneous measurement of ordinary UV/vis absorbance spectra from the photomultiplier high voltage output during a circular dichroism measurement is accurate and reliable. The photometric accuracy and linearity of various spectrometers is determined using standard solutions of potassium dichromate. The mathematical treatment of the signal representing the high voltage applied to the detector is presented here. An ordinary UV-vis spectrophotometer was used to measure the direct UV absorbance for comparison and to assign a reference value (Z-Value) to each CD spectrometer. The results proved to be accurate and reliable.

Children especially infants are particularly sensitive to contaminant exposure, they are exposed to toxic substances including heavy metals via multiple pathways, i.e. food, air, water, soil and childcare products. To date, determination of metal bioaccessibility in teethers and feeding teats is missing in the literature; therefore, it is vitally important to assess their metal bioaccessibility and characterise the risk for children. The aim of this study is to determine the migration levels of toxic elements in teethers and feeding teats of different brands as a measure of metal bioaccessibility and characterise the risk for children exposed to these products. The migration limits of several heavy metals (Al, As, Ba, Cd, Co, Cu, Cr, Mn, Ni, Pb, Se, Sr, Zn) in different brands of teethers and feeding teats were determined simultaneously using inductively coupled plasma optical emission spectroscopy (ICP-OES) adopting a protocol in the European standards for safety of toys. With the exception of Pb, the migration limits of all elements in all brands of teethers and feeding teats were below the specified limits. However, in the case of Pb, the migration was above the specified limits in all samples except one brand of feeding teats. Risk assessment expressed as hazard index (HI) was calculated for detected elements and all samples. Although HI was below 1.0 for all samples except one sample, the high Pb concentration would pose a considerable risk to children. Therefore, we recommend a more thorough research and risk characterisation taking into consideration the factors that affect HI values. Graphical Abstract Determination of metal bioaccessibility and risk characterisation of teethers and feeding teats ensure children safety against metal toxicity.

The current situation presents a pressing need to reduce pharmacokinetic variations of drugs in cancer patients. Although most of the omics technologies are not entirely focussed on the study of pharmacokinetic variations and some studies are met with uncertainty, the use of pharmacometabolomics combined with other omics technology such as pharmacogenomics can provide clues to personalised cancer treatments by providing useful information about the cancer patient's response to medical interventions via identification of patients' dependent variables, understanding of correlations between individuals and population PKs, and therapy outcomes to achieve optimum therapeutic effects with minimum toxicity. We also propose an approach for PKs' evaluation using pharmacometabolomics.

Drug-induced hepatotoxicity (DIH) is an unpredictable and frequent event with the risk of a life threatening clinical course when it occurs. The detection of hepatotoxic effects is a continuous process covering all drug development phases. Various in vitro liver models have been developed in the past years. However, the high chemical diversity of biological samples and sample's characteristics make the prospect of detecting DIH a difficult and complicated process. Therefore, a good understanding of toxic effects of drugs on the liver and the viability of the experimental models as the main source of samples are essential platforms which are needed for any analytical technique. Major analytical techniques such as hyphenated systems, e.g. chromatography and mass spectrometry (MS) play a pivotal role in the detection of DIH. Nevertheless, these state of the art techniques are not without limitations. This review focuses on highlighting the main aspects of DIH; the applications of mass spectrometry based metabonomics, their applicability with regard to sample availability and comparison with standard clinical chemistry applications. We also propose an approach to study DIH in the early phase of drug discovery. The aim of this paper is foremost to provide an overview and guidance to study and facilitate further discussions on this topic.

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