胰蛋白酶和三种纳米材料相互作用的研究

Interaction of trypsin with nanomaterials

采用紫外可见、荧光、圆二色光谱法,研究了纳米SiO_2、纳米TiO_2、纳米石墨粉对胰蛋白酶的催化活性及结构的影响。实验表明,三种纳米材料的存在均减弱胰蛋白酶的活性;纳米TiO_2和纳米石墨粉分别通过氢键和范德华力和胰蛋白酶结合从而猝灭酶的内源荧光,纳米SiO_2通过疏水作用猝灭胰蛋白酶的荧光。圆二色光谱研究表明,纳米TiO_2、纳米石墨粉的存在改变了胰蛋白酶的二级结构,纳米SiO_2的存在不改变胰蛋白酶的结构。

The effects of nano-SiO2 ,nano-TiO2 and nano graphite powder on the catalytic activity and structures of trypsin were in-vestigated by ultraviolet visible（ UV-Vis） ,fluorescence and circular dichroism spectroscopies. Experiments indicated that the pres-ence of the three nanomaterials inhibited the activity of trypsin. Nano-Ti02 and nano graphite powder quenched the intrinsic fluores-cence of trypsin through binding with the enzyme via hydrogen bonding and van der Waals forces. Nano-SiO2 quenched the fluores-cence of trypsin via hydrophobic interaction. Circular dichroism spectroscopy showed that the presence of nano-TiO2 and nano graph-ite powder changed the secondary structures of trypsin. However,the presence of Nano-SiO2 did not change the secondary structures of trypsin.