硅酸甘油二酯的水解及凝胶化行为

HYDROLYSIS AND GELATION BEHAVIOR OF DIGLYCEROL SILICATE

制备了硅溶胶前驱体硅酸甘油二酯(diglycerol silicate,DGS),利用动态光散射跟踪法考察了其水解和凝胶过程。结果表明:所制备的DGS纯度较高,水解后形成的硅溶胶粒子zeta电位为-12.56mV。离子强度、蛋白种类及浓度均对硅溶胶-凝胶体系的胶凝时间和凝胶状态有影响。在凝胶温度为30℃,DGS质量分数为10%,离子浓度为2mmol/L,蛋白质量分数为0.13%时,可获得均匀性较好的凝胶体系,该体系凝胶时间为30min。DGS水解产物的自相关函数变化和散射光强变化均为典型硅凝胶体系的变化。该体系可作为维持生物大分子活性的理想体系。

A precursor of the silica sol,diglycerol silicate（DGS）,was prepared,and its hydrolysis and gelation process were investigated by dynamic light scattering tracing method.The results show that the prepared DGS is highly pure,and the zeta potential of the silica particles formed by the hydrolysis of DGS is-12.56 mV.The ionic strength,the type and the concentration of proteins can affect the gelation time and the state of the silica sol-gel system.When the gelation temperature is 30 ℃,the mass fraction of DGS is 10%,the ionic concentration is 2 mmol/L,and the mass fraction of protein is 0.13%,a uniform gel system can be obtained,and the gelation time is 30 min.The autocorrelation function and the strength of the scattering light of the hydrolysis products from DGS exhibits typical changes as in most silica gel systems.The system is ideal for the preservation of biomacromolecules.