High definition sinchrotron X-ray powder diffraction used to investigate phase diagram of kidney calculi stones

Abstract

The high definition sinchrotron X-ray powder diffraction (XRPD) technique was used to study the crystalline phase structural stability of human renal calculi under thermal treatment. The stones were colleted from 85 donors of Vit´oria City, Esp´ ırito Santo State- southeast- Brazil. A high definition sinchrotron X-ray powder diffraction was performed on one monophasic sample classified by a normal X-ray diffraction technique , which reveals that 61nucleation process developed in closed kidney cavities. A study of in situ the phase transformation of monohydrate calcium oxalate into calcium carbonate (CaCO3) was carried out by annealing of a monophasic monohydrate calcium oxalate calculi at 100o C, 150oC, 300o C, 350oC, 400o C and 500oC temperatures. A high definition sinchrotron X-ray powder diffraction data carried out from the in situ experiment indicated that there is a no structural water which occupied a interstitial grain boundary among the grains. We concluded that high definition sinchrotron X-ray powder diffraction is a important tool which can be used as suitable technique to study the phase diagram of renal calculi.