The evaluation and implementation of a commercially available, off the shelf, analytical SFC=MS and a mass directed, semi-preparative SFC-MS system for use in a high throughput purification laboratory is described. The advantages of the use of SFC to support high throughput purification includes rapid evaporation of the chromatographic mobile phase in isolated fractions, resulting in faster sample turnaround time. In addition, SFC provides a complimentary separation technique based on normal phase, adsorption chromatography mechanisms. The screening scheme employed on the associated analytical SFC-MS and the methodology developed for the mass directed, semi-prep SFC-MS are presented in detail. The utilization of standard FractionLynx=AutoPurify functionalities to enable rapid incorporation into high throughput environments is also emphasized.

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A new colorimetric optode has been developed for preconcentration and visual determination of mercury ions in fish products. This optode is based on the color reaction of copper diethyldithiocarbamate with Hg2+ in the body of polymethylmethacrylate matrix. The optode exhibited sensitivity through the change of color from brown to colorless, which could be easily detected by naked-eye or spectrophotometric method. The influence of acidity, contact time and interference of foreign metal ions has been studied. The optode revealed good linearity in the range of 20-360 μg·L-1, with a limit of detection of 8 μg·L-1 Hg2+ at pH 5.2 and response time of 10 min.

Tartrazine E102, Yellow "Sunset" E110, Ponso 4R E124 and the Patented Blue E131 food synthetic dyes solid-phase extraction from yoghurts and biokefirs in a transparent polymethylmethacrylate matrix as a solid extractant was studied. The analytical signal was formed due to the accumulation of the dye in the volume of the polymer matrix without violating the transparency, and this corresponded to the wavelength of the maximum absorption of the corresponding dye. The sorption mechanism was based on the protonization of the carbonyl groups of PMM in the acidic media, and, as a result, the optode surface became positively charged. Therefore, the sorption of the R ± form of the E131 dye and the azo dye anions occurred by the positively charged PMM surface. The effectiveness of the proposed approach was shown for the identification and determination of the 2 food-grade synthetic dyes content using the visual and spectrophotometric methods. The optimal conditions for the analysis corresponded to pH <3, the duration of dye extraction into the polymer matrix was 20 min, the range of the detected concentrations was 0.2-40.0 mg / kg with the detection limit of 0.05 mg/kg, and an excess of sweeteners and preservatives did not significantly affect the results of the analysis. The results of the determination of the listed dyes were demonstrated in the current work for the case of individual and group presence of dyes in biokefirs and yogurts. The proposed technique is simple in execution and could be carried out using the standard spectrophotometric equipment. The advantage of the developed method for the determination of artificial dyes in comparison with the method of spectrophotometric determination with liquid extraction is a significant increase in the sensitivity of determination due to the accumulation of analyte, the exclusion of turbidity of an aliquot and the absence of dye loss due to its transition into the supernatant, and then into the solid phase of the matrix.