Structure of Amorphous Platinum Uridine Green Sulfate by AWAXS and EXAFS

Abstract

Amorphous platinum uridine green sulfate was studied using anomalous wide-angle X-ray scattering and X-ray absorption techniques. Experiments were made with synchrotron radiation in the vicinity of the Pt LIII absorption edge. The experimental results agree with a mixture model where the major components are mono- and dinuclear Pt complexes. The intramolecular Pt−Pt distance of 3 Å and the shortest intermolecular Pt−Pt distances of 5.1 and 7.3 Å were determined from the approximative regularized Pt−Pt partial radial distribution function. The shortest average Pt−O and Pt−N distance of 2.03 Å was obtained from the EXAFS data.

Copper and copper oxide nanoparticles in a cellulose support studied using anomalous small-angle X-ray scattering

“…The solved PSFs are affected by statistical errors of the intensities, errors in the normalization of the intensities onto the absolute intensity scale, and errors in f b or f b [27]. The effect of small errors may be huge: S ab (q) may become a negative mirror image of the dominating S bb (q), while S aa (q) may become a positive mirror image of S bb (q).…”

Structural study of amorphous platinum 5-fluorouridine green sulfate

“…The positions of the most pronounced maxima of ∆RDF and ∆DDF are given in Table 1 along with the selected results for platinum uridine green sulfate. 33 The precision of the positions of the maxima is about ±0.03 Å. It is noted that the true atomic distances may differ from these positions due to overlapping of the peaks and termination ripples in the Fourier transformation.…”

“…[17][18][19][20] The present knowledge about the correlation between the structure and the chemical nature of the amorphous platinum blues is largely based on the studies of crystalline platinum pyrimidine complexes, 17,21-23 the breakthrough being the crystal structure determination of tetranuclear platinum α-pyridone blue. 24 Studies on amorphous platinum nucleoside (modified nucleosides) complexes in the solid state have been carried out by extended X-ray absorption fine structure (EXAFS), 25, 26 wide angle X-ray scattering (WAXS), [27][28][29][30][31] anomalous wide angle X-ray scattering (AWAXS), 32, 33 small angle X-ray scattering (SAXS) 34 and in solution by SAXS, 3,30,31, 35 UV/VIS spectroscopy 36-38 and 195 Pt, 15 N and 13 C NMR spectroscopy. 37,39,40 Recently the structure of platinum uridine green sulfate was studied in the solid state by AWAXS and EXAFS methods.…”

“…The studies showed that it is a mixture of di-and mono-nuclear platinum complexes. 33 In this AWAXS study the research is continued by studying the effects of substitution of the ligand on the average platinum nuclearity in the solid state. 5-Fluorouridine 41 and its derivatives 42 are cytotoxic.…”

X-Ray Absorption Spectroscopy and Anomalous Wide Angle X-Ray Scattering: Two Basic Tools in the Analysis of Heterogeneous Catalysts

“…Various kinds of systems [148,149] such as supported metallic clusters [150][151][152], Pt-Mo [153,154], Pt-Re [155] catalysts or oxide compounds [156][157][158][159] have been investigated. For data analysis by direct comparison of calculated and experimental intensities, the first step is to set up a plausible model of the material and calculate the interatomic distances between all pairs of atoms [160].…”