Artículo de publicación ISIPathological crystallization of calcium oxalate (CaOx) inside the urinary tract is called calculi or kidney stone (Urolithiasis). CaOx exhibits three crystalline types in nature: CaOx monohydrate COM, dihydrate COD and trihydrate COT. COD and COM are often found in urinary calculi, particularly COM. Electrocrystallization has been recently used to perform oriented crystallization of inorganic compounds such as Ca-salts. Although many mineralization methods exist, the mechanisms involved in the control of CaOx polymorphism still remain unclear. Herein, we induced selective electrocrystallization of COD by modifying the electrical current, time and electrochemical cell type. By combining above factors, we established an efficient method without the use of additives for stabilizing non-pathological CaOx crystals. We found notorious stabilization of CaOx polymorphisms with hierarchically complex shape with nano-organization assembly, size and aggregated crystalline particles. Our results demonstrated that, by using an optimized electrochemical approach, this technique could have great potential for studying the nucleation and crystal growth of CaOx through functionalized synthetic polymers, and to develop a novel pathway to evaluate new calculi preventing-compound inhibitors

The electrocrystallization (EC) of calcium oxalate (CaOx) crystals in the presence of multiwalled carbon nanotubes (MWCNTs) functionalized with itaconic acid (IA) and the monoester derivatives monomethylitaconate or mono-octadecylitaconate, which were used as new IA-ester templates supported on indium tin oxide glass substrate as working electrode, was performed by applying a 9 mA current at 37 and 60 °C for 5 min. Under the above EC reaction conditions, a broad variety of CaOx morphologies and crystal forms was found. The morphology control and coexistence of CaOx monohydrate (COM) and CaOx dihydrate was achieved through in vitro EC according to X-ray diffraction spectra. We found that all the functionalized MWCNTs were more efficient inhibitors of CaOx crystallization than the typical citrate model, where MWCNT-IA was the most effective stabilizing template of COM crystals, because carboxylic acid groups of IA moieties in MWCNT-IA would be better Ca 2+ ions binding sites than IA ester groups.