Abstract. The creation of Cu2+ ions chelate complex with 1-(5-benzylthiazol-2-yl)azonaphthalen-2-ol has been investigated using spectrophotometric methods. The optimal conditions for the complexation reaction and for extraction into the organic phase were found. The extraction-photometric method of copper microquantities determination was developed.

The interaction of Pd(II) with 5-hydroxyimino-4-imino-1,3-thiazolidin-2-one (HITO) was investigated over the pH range of 1.0–10.0. Optimal conditions for the voltammetric determination of Pd(II) were established. A new voltammetric method of Pd(II) determination by the peak of complex using NaCl as a supporting electrolyte at pH 2.0 was developed with the limit of detection 2.0∙10-7 M. The study of the method’s selectivity was presented in the work. The correctness of the method was confirmed by the analysis of model solutions and the real sample (resistor SP5-35B).

5-Hydroxyimino-4-imino-1,3-thiazolidine-2-one has been suggested as a new organic reagent for the voltammetric determination of platinum. The optimal conditions of Pt(IV) voltammetric determination using 5-hydroxyimino-4- imino-1,3-thiazolidine-2-one on the peak of catalytic hydrogen currents have been determined: the background electrolyte is 0.3 M NaCl, pH of the solution is 2.0, 50-fold concentration excess of organic reagent. The sensitive method of Pt(IV) voltammetric determination was developed (LOD = 4.1·10-9 М). The range of determinable contents covers two concentration orders. The selectivity of the developed methods have been studied towards concomitant metals ions. The accuracy of the developed method has been tested on model solutions using “added-found” method. The method has been approved during the analysis of a real sample, viz. the catalyst for oxidation of exhaust gases of the car “Chevrolet”.

This work describes the application of a new, simple and rapid spectrophotometric method to the determination of palladium in the intermetallides Yb 40 Pd 38 Sn 22 and Yb 40 Pd 40 Ga 20. The method is based on the interaction of palladium(II) ions with 5-hydroxyimino-4-imino-1,3-thiazolidin-2-one at pH = 5.0, in a medium of acetate buffer and sodium chloride. The range of the determined concentrations of palladium is 6.0•10-6-6.0•10-5 M. Intermetallides / Palladium(II) / Spectrophotometry / 5-hydroxyimino-4-imino-1,3-thiazolidin-2-one

A rapid, simple and sensitive spectrophotometric method for the determination of amoxicillin (AM) is described. The method is based on the previous sulphanilamide (SA) and sulphathiazole (STZ) diazotization in the medium of 0.6-0.7 M hydrochloric acid and their subsequent interaction with amoxicillin at pH = 10.5 with formation of yellow-colored azo compouds. Effective molar absorptivities at the absorbance maxima at 445 nm (SA) and 448 nm (STZ) for azo compounds were (1.74 ± 0.06) • 10 4 L × mol-1 × cm-1 and (1.97 ± 0.05) • 10 4 L × mol-1 × cm-1 , respectively. Stoichiometric ratios of the components of azo compounds were determined using continuous variations method. Based on the optimum reaction conditions, new methods were developed. These methods allow to determine the amoxicillin in concentration range 1.3-32.9 mg × mL-1 with sulphanilamide and 0.7-27.4 mg × mL-1 with sulphathiazole. The methods were successfully validated for amoxicillin determination in tablets "Amoxil".