An inner-filter-effect based ratiometric fluorescent sensor for the detection of uranyl ions in real samples

In this work, a ratiometric fluorescence system was designed for detection of trace UO22+ in water based on inner filter effect (IFE) between gold nanoparticles (AuNPs) and gold nanoclusters (AuNCs)....

Cloud point extraction associated with differential pulse voltammetry: preconcentration and determination of trace uranyl in natural water

A procedure for electroanalytical determination of the uranyl ions pre-concentrated from natural water by cloud point extraction (CPE) was developed in this work. The CPE parameters, such as surfactant concentration,...

Abnormal activity of functional groups during uranyl ions sorption by polymethacrylic acid-poly-4-vinylpyridine intergel system

Uranyl ions sorption by intergel system consisting of polymethacrylic acid hydrogel (hPMAA) and poly-4-vinylpyridine hydrogel (hP4VP) has been studied. First, reciprocal activation of PMAA and P4VP polymeric hydrogels in water environment was examined in order to predict intergel system sorption activity. Based on the obtained results, it was found that area of maximum hydrogel activation was within the ratios of 100 % hPMAA and 67 % hPMAA:33 % hP4VP. The maximum rate of uranyl ions extraction was also observed within these ratios. The highest uranyl ions sorption by intergel system occurred at 83 %hPMAA:17 % hP4VP ratio. Maximum uranyl ions extraction rate after 56 hours of hydrogels remote interaction was 82.5 %, when polymeric chain binding rate was 9.94 % and effective dynamic exchange capacity was 1.12 mmol/g. Significant increase of intergel system sorption activity within the ratios of 100 % hPMAA and 67 % hPMAA:33 % hP4VP in comparison with initial inactivated hydrogels 100 % hPMAA and 100 % hP4VP was confirmed by combined calculation data of extraction rates of inactivated PMAA and P4VP polymeric hydrogels. The obtained results illustrated changes of initial polymeric hydrogels’ electrochemical sorption properties in intergel system leading to functional groups obtaining higher reactive ability, which made it possible to use them for further development of highly efficient uranyl ions extraction sorption technology

Expression of Cytochrome c3 from Desulfovibrio vulgaris in Plant Leaves Enhances Uranium Uptake and Tolerance of Tobacco

Cytochrome c3 (uranyl reductase) from Desulfovibrio vulgaris can reduce uranium in bacterial cells and in cell-free systems. This gene was introduced in tobacco under control of the RbcS promoter, and the resulting transgenic plants accumulated uranium when grown on a uranyl ion containing medium. The uptaken uranium was detected by EM in chloroplasts. In the presence of uranyl ions in sublethal concentration, the transgenic plants grew phenotypically normal while the control plants’ development was impaired. The data on uranium oxidation state in the transgenic plants and the possible uses of uranium hyperaccumulation by plants for environmental cleanup are discussed.

Specific features of uranyl ions extraction by interpolymer system based on polyacrylic acid and polyethyleneimine hydrogels

Uranyl ions sorption of by interpolymer system consisting of polyacrylic acid hydrogel (hPAA) and polyethyleneimine hydrogel (hPEI) has been studied. Rate of uranyl ions extraction by the initial polymers and interpolymer system hPAA-hPEI, polymeric chain binding rate and dynamic exchange capacity of initial polymers and interpolymer system hPAA-hPEI were calculated. Based on obtained outcomes it was found that area of maximum rate of uranyl ions extraction is within the ratios of 67%hPAA:33%hPEI and 33%hPAA:67%hPEI. Maximum uranyl ions extraction rate after 48 hours of hydrogels remote interaction was 90.0 %, when polymeric chain binding rate was 9.1 % and dynamic exchange capacity was 1.14 mmol/g. Rate of uranyl ions extraction by the initial polymer hydrogels 100 % hPAA and 100 % hPEI was 68.0 % and 52.0%. Obtained outcomes showed changes of initial polymeric hydrogels sorption properties in intergel system leading to functional groups obtaining higher reactive ability, which makes it possible to use them for further development of highly efficient uranyl ions extraction sorption technology.