Effects of temperature and sodium carboxylate additives on mineralization of calcium oxalate in silica gel systems

作     者：Bernd Tieke 

作者机构：Institut fur Physikalische Chemie Universitt zu Kln Luxemburgerstr. 116 D-50939 Kln Germany 

出 版 物：《Science China Chemistry》 (中国科学（化学英文版）)

年 卷 期：2004年第47卷第4期

页      面：311-319页

核心收录：

学科分类：081704[工学-应用化学] 07[理学] 08[工学] 0817[工学-化学工程与技术] 0703[理学-化学] 070301[理学-无机化学] 

基　　金：This research work was supported by the National Natural Science Foundation of China(Grant No.20031010) the Key Project of Natural Science Foundation of Guangdong Province(Grant No.013202) the Key Project of Guangdong Province(Grant No.C31401) a Fellowship of Alexander yon Humboldt-Stiftung of Germany 

主　　题：calcium oxalate sodium carboxylate gel urinary calculi crystallization biomineralization 

摘      要：The effects of temperature and multifunctional sodium carboxylate additives on the phase composition and morphology of calcium oxalate (CaOxa) crystals grown in silica gel system were systematically investigated using scanning electron microscopy (SEM), powder X-ray diffraction (XRD), and Fourier-transform infrared spectra (FT-IR). The sodium carboxylates investigated include: monocarboxylate sodium acetate (NaAc), disodium tartrate (Na2tart), trisodium citrate (Na3cit), and the disodium salt of ethylenediaminetetraacetic acid (Na2edta). The temperature range was from 7°C to 67°C. The crystallization temperature affects the phase compositions, the growth rate, and the morphology of CaOxa. First, the logarithm of the percentage of calcium oxalate dihydrate (COD) formed at a certain temperature (T) is proportional to the reciprocal of temperature (1/T). Second, the weight of CaOxa crystals decreases as decreasing the temperature. At a given temperature, the ability of the sodium carboxylates to induce COD follows the order: Na2edta Na3cit Na2tart NaAc. Third, the multicarboxylates can decrease the surface area of calcium oxalate monohydrate (COM). It makes the edges and tips of COM crystals blunt and oval. All the three changes, an increase of the content of COD, a decrease of the weight of CaOxa crystals, and a decrease of the surface area of COM crystals, can inhibit the formation of CaOxa stones. These results support the clinical use of citrates and may be helpful in elucidating the mechanisms of the formation of CaOxa calculus. Keywords calcium oxalate - sodium carboxylate - gel - urinary calculi - crystallization - biomineralization