Effect of Unitary, Binary and Ternary Carboxylates on Crystallization Kinetics of Calcium Oxalate in Artificial Urine

Abstract

Urolithiasis is a chronic disease with an incidence increasing annually, may relapse after treatment 1. Calcium oxalate (CaC2O4) is the main component of urinary stones. Stone formation involves nucleation, growth, aggregation and adhesion process of urinary crystallites. The complexity of the internal environment in the human body, observing the formation processes of stones in situ is difficult. Therefore, we usually use the simulative method in vitro to study the nucleation, growth and aggregation of CaC2O4 and the influence of various inhibitors on these processes 1. These simulative systems contain water, urine, artificial urine, membrane mimetic system, surface of renal epithelial cells, etc 2-5. Nishio et al. 6 studied the inhibition effects of prothrombin fragment 1 and osteopontin on CaC2O4 crystallization in artificial urine, indicating that the inhibition effects of the two proteins on the growth rate of CaC2O4 were 27 and 32 %, respectively, when their concentration were 2 µg/mL. Wang et al. 7 studied the inhibition effect of phosphorylated osteopontin segment on nucleation and growth of calcium oxalate monohydrate (COM) crystals under near-physiological pH, temperature and ionic strength. When the concentration of phosphorylated OPN was 43.9 nm, the growth rate of CaC2O4•H2O