Selective online solid-phase extraction of copper using p-morpholino-methylcalix[4]arene appended silica-based column

A Review on the Analysis of Chiral Molecules as Disease Biomarkers by LC/MS

The chiral compounds may be biomarker candidates in human metabolism, which indicates the health status of humans. There are many applications in LC/MS that show that chiral small molecules are promising biomarkers for human diseases. Both clinical and commercial analyses of chiral metabolites are necessary due to the enantiomeric ratios of chiral molecules in biological samples may show both human health status and diseases. This review provides current and advanced LC/MS techniques for the separation and analysis of chiral molecules as disease biomarkers. In particular, sample preparation and chromatographic analysis of potential chiral biomarkers in biological samples are presented. The preparation and applications of several chiral columns used in enantiomeric separation of chiral metabolites/biomarkers by advanced LC/MS techniques are discussed. The improvement of these analyses will enable both the discovery of new chiral biomarkers and the prognosis of human diseases.

Simultaneous Spectrometric Determination of Cu(II), Co(II), and Ni(II) in Pharmaceutical and Environmental Samples with XAD-4/DMMDTC Solid-Phase Extraction System

A method for the preconcentration of Cu(II), Co(II), and Ni(II) based on their complex formation with the potassium salt of 2.6-dimethyl-morpholinedithiocarbamate (DMMDTC) and the Amberlite XAD-4 resin as a solid support in a column was suggested. Cu(II), Co(II), and Ni(II) were detected by using the suggested spectrophotometric method in Triton X-100 media. The analytes were adsorbed as DMMDTC complexes on Amberlite XAD-4 column at the pH range of 4-6 and eluted with 0.5 M HNO₃ in acetone. The best possible enrichment factors for trace metal ions were achieved by optimizing the experimental conditions including reagent amount, eluent type, sample and eluent flow rates, sample volume, and the effects of matrix ions. The detection limits of Cu(II), Co(II), and Ni(II) were found to be 11.2, 26.1, and 1.37 μg L^-1, respectively. The accuracy of the proposed method was confirmed by determining the analytes in two Certified Reference Materials (TMDA-70.2 Ontario Lake Water and BCR-715 Waste Water) with the recoveries of more than 90%. The proposed method was successfully applied to the environmental and pharmaceutical samples.