Crystallization Of Calcium Oxalate Crystals In Liposome Solutions And The Guidance On Medicine Selection For Urolithiasis

The nucleation and growth of calcium oxalate (CaOxa) crystals in liposome solutions was investigated using Laser Light Scattering Spectroscopy and Transmission Electron Microscopy (TEM). The mean diameter of liposomes was 111.2 nm and 168.9 nm, respectively, for the concentration of PC of 4.2 mmol/L and 6.7 mmol/L. The diameter of the CaOxa crystals grown in the liposomes was about 100 nm, it is much smaller than that in pure water, which has a size of about 1000 nm.The morphology of CaOxa crystal grown in PC liposome under different conditions was investigated using X-Ray diffraction (XRD). As the reaction time and standing time increase, the percentage of calcium oxalate trihydrate (COT) decreases and the percentage of the thermodynamic stable calcium oxalate monohydrate (COM) increases. The metastable calcium oxalate dihydrate (COD) is not observed.Under a reaction time of 10 minutes and a standing time of 2 hr, the morphology and phases CaOxa crystals become approximately constant. The effect of different additives, such as carboxylate and magnesium chlorate, etc., on the CaOxa crystal was investigated in liposomes. Multicarboxylate and MgCb were able to inhibit COM formation and favor COD and COT growth. However, monocarboxylates, regardless of their molecular amount or structure, have no this ability. At the same conditions, the ability to suppress the formation of COM and thereby to favor COD follows the order Citrate > Editate > Tartrate, and the ability to induce the COT formation follows the order Tartrate > Citrate > Editate.The relationship between the CaOxa stones growth and the morphology of CaOxa crystals was discussed. The reasons why multicarboxylate such as citrates and tartrates were used as stone inhibitors in clinic were also discussed. Our results supported that citrates are the best medicine in preventing and curing CaOxa stones.