Detection of the mineral constituents in human renal calculi by vibrational spectroscopic analysis combined with allied techniques Powder XRD, TGA, SEM, IR imaging and TXRF.

Detection of the mineral constituents in a batch of 310 samples of human urinary calculi (kidney stones-235 and bladder stones-75) combined with a semi-quantitative analysis has been presented on the basis of Fourier Transform based IR and Raman spectral measurements. Some of the observed characteristic IR and Raman bands have been proposed as 'Marker Bands' for the most reliable identification of the constituents. A detailed vibrational spectral analysis combined with a DFT level calculation for the functional groups in Calcium Oxalate Monohydrate (COM), Magnesium Ammonium Phosphate Hexahydrate (MAPH), Calcium Hydrogen Phosphate Dihydrate (CHPD), Penta-Calcium Hydroxy-Triphosphate (PCHT) and Uric Acid (UA) has been proposed. It has been shown that the identified mineral constituents as major or minor components can be deduced from the application of Lambert-Beer law of radiation absorption and results are in agreement with quantitative Spectral Data base. This simple method has the potential to be integrated into the management of Urolithiasis, a process of forming renal calculi in the kidney, bladder and/or urethra. Employment of powder XRD, TGA, SEM, TXRF and IR Imaging techniques has provided additional support for the proposed foolproof identification of the mineral constituents. Among the mineral constituents, Calcium Oxalate Monohydrate, Calcium Oxalate Dihydrate or their mixture account for 85% of the total number of samples; the remaining 15% and 5% samples contain Phosphate and Uric acid stones respectively.

Effect of Nickel Doping on the Properties of Hydroxyapatite Nanoparticles.

Herein, we studied the effect of nickel (Ni) doping on the properties of hydroxyapatite (HAp) nanoparticles synthesized by facile ultrasonication assisted wet chemical synthesis process. Various doping concentrations of nickel, i.e., 0.01 M, 0.05 M and 0.10 M, were used to dope into hydroxyapatite nanoparticles. The synthesized nanoparticles were characterized by X-ray diffraction (XRD) pattern, scanning electron spectroscopy (SEM), Fourier transform infrared (FTIR) spectroscopy, UV-Visible spectroscopy and Raman-scattering spectroscopy. The detailed structural characterizations confirmed that the crystallite sizes of the Ni-doped hydroxyapatite nanoparticles were reduced up to 53% compared to pure hydroxyapatite upon the doping of different concentrations of Ni ions. The agglomeration in the nanoparticles was also reduced by increasing the doping concentration of Ni ions. The XRD studies revealed that the average crystallite size of the synthesized Ni-doped HAp was decreased with increasing the concentration of Ni2+ ion doping and this observation was well-consistent with the SEM results. The FTIR and Raman studies well-confirmed the formation of pure HAp and Ni-doped HAp. Further, doping with Ni creates a new level of energy between the conductive band and the valence band and hence with increasing the concentration of Ni2+, the intensity in the UV-vis spectra was enhanced.

Morphological and elemental mapping of gallstones using synchrotron microtomography and synchrotron X-ray fluorescence spectroscopy.

BACKGROUND AND AIM: Regional differences in gallstone (GS) composition are well documented in the Indian subcontinent. The reasons for the same are unknown. Etiopathogenesis of GS remains elusive despite advances in instrumentation. This was an in-depth analysis of the chemical, structural, and elemental composition of GS with special reference to synchroton studies. METHODS: We used high-end sensitive analytical complementary microscopic and spectroscopic methods techniques, such as X-ray diffraction, scanning electron microscopy, Fourier transform infrared, synchrotron X-ray fluorescence spectroscopy (SR-XRF), and 2D and 3D synchrotron microtomography (SR-µCT), to study the ultra structure and trace element composition of three major types of GS (cholesterol, mixed, and pigment). SR-XRF quantified the trace elements in GS. RESULTS: The cholesterol GS (monohydrate and anhydrate) were crystalline, with high calcium content. The pigment GS were amorphous, featureless, black, and fragile, with high calcium bilirubinate and carbonate salts. They had the highest concentration of iron (average 31.50 ppm) and copper (average 92.73 ppm), with bacterial inclusion. The mixed stones had features of both cholesterol and pigment GS with intermediate levels of copper (average 20.8 ppm) and iron (average 17.78 ppm). CONCLUSION: SR-µCT has, for the first time, provided cross-sectional computed imaging delineating the framework of GS and mineral distribution. It provided excellent mapping of cholesterol GS. SR-XRF confirmed that pigment GS had high concentrations of copper and iron with bacterial inclusions, the latter possibly serving as a nidus to the formation of these stones.

Chemical and structural analysis of gallstones from the Indian subcontinent.

Representative gallstones from north and southern parts of India were analyzed by a combination of physicochemical methods: X-ray diffraction (XRD), infrared spectroscopy (IR), scanning electron microscopy (SEM), energy-dispersive X-ray spectroscopy (EDX), CHNS analysis, thermal analysis and Nuclear Magnetic Resonance (NMR) spectroscopy (1H and 13C). The stones from north Indian were predominantly consisting of cholesterol monohydrate and anhydrous cholesterol which was confirmed by XRD analysis. FTIR spectroscopy confirmed the presence of cholesterol and calcium bilirubinate in the south Indian gallstones. EDX spectroscopy revealed the presence of carbon, nitrogen, oxygen, calcium, sulfur, sodium and magnesium and chloride in both south Indian and north Indian gallstones. FTIR and NMR spectroscopy confirmed the occurrence of cholesterol in north Indian gallstones. The respective colour of the north Indian and south Indian gallstones was yellowish and black. The morphology of the constituent crystals of the north Indian and south Indian gallstones were platy and globular respectively. The appreciable variation in colour, morphology and composition of south and north Indian gallstones may be due to different food habit and habitat.