SBA-15/酶纳米反应器的扩散和动力学

将猪胰脂肪酶固定于不同孔径SBA-15载体的孔道内,将已固定酶的尺寸分布均一的一维孔道看作纳米反应器,研究了酶催化水解反应的内扩散和动力学特征。蒂勒模数和有效扩散系数随孔径尺寸的变化以及动力学参数和内扩散之间的关系说明:当孔径小于9.4nm时,内扩散限制明显;孔径大于10.9nm时,内扩散对酶催化水解过程的影响减小。

Diffusion and kinetics of nanoreactors based on SBA-15 and enzyme

Porcine pancreatic lipase (PPL) has been immobilized in the mesoporous channels of SBA-15 possessing different pore diameters. The nano-sized channels entrapping enzymes could be considered as nanoreactors due to the narrow pore-size distribution and one-dimensional channels of the host, and the internal diffusion and kinetics in the enzymatic hydrolysis have been investigated. The dependence of the Thiele modulus and the internal effectiveness factors on the pore size, as well as the correlation of kinetic parameters with the internal diffusion, indicate that, in the range of pore size <9.4 nm, the internal diffusion limitation significantly occurred, when pore size was larger than 10.9 nm, the internal diffusion limitation made less impact on the enzymatic reaction.