Vishnikin A. Modified forms of heteropoly anions in spectroscopic methods of analysis

The thesis is devoted to the search of modified analytical forms and analytical reagents for the application in spectroscopoic methods of the analysis based on the formation reactions of oxidized, reduced, mono- and mixed ligand, metalsubstituted heteropoly anions (HPA) of P(V), As(V), Si(IV), Ge(IV), Ga(III) or their ion associates (ІА) with basic dyes. Methods for the synthesis of molybdenum metalsubstituted HPAs XMeM11O40n-, where Ме = Ti(IV), Bi(III) і Sb(III), X = P(V), Ga(III), M = Mo(VI), W(VI), have been developed. Conditions for the sorption separation of ІА of HPAs with triphenylmethane dyes from the dye excess (selective protonation) and ІА with isopoly molybdate ions (masking with oxy acids) on polyurethane foams and paper were found. For the first time, IA of HPA with polymethine dyes were proposed for the fast, highly sensitive and selective spectrophotometric, luminescent, sequential injection determination of P(V) and As(V). To increase the sensitivity of atomic-absorption and X-ray fluorescent determination of P(V), separation of excess of metal ions from the metalsubstituted HPAs on the cation ion exchange resin in Na+-form or selective sorption and preconcentration of 11-molybdo-2-bismuthophosphate HPA on polyurethane foam have been proposed. 11-molybdobismuthophosphate and 18-molybdodiphosphate HPAs were proposed as new effective reagents for the determіnation of ascorbic acіd and other reducers. Metalsubstituted HPAs were used as analytical reagents for the determination of peroxo compounds and sulfide containing species.