化工学报2019，Vol.70Issue(5)：1887-1893,7.DOI:10.11949/j.issn.0438-1157.20181423
聚乙烯亚胺/多巴胺改性氧化硅固定碳酸酐酶
Immobilization of carbonic anhydrase on polyethylenimine/dopamine co-deposited SiO2
摘要
Abstract
Silica was modified by a polyethyleneimine (PEI)/dopamine (DA) co-deposition method, and then carbonic anhydrase (CA) was covalently immobilized via glutaraldehyde (GA). First, the effects of the mass ratio of PEI and DA, deposition time on the deposition rate were investigated, and silica microspheres before and after modification were characterized by Fourier transform infrared spectroscopy (FTIR) and scanning electron microscope (SEM). Then, the influences of the immobilization conditions including the deposition rate, the addition amount of PEI/PDA-SiO2, CA and GA concentration on the activity recovery of immobilized enzyme were studied. At last, the storage stability and reusability of immobilized enzyme were also examined. The results show that the deposition rate increased firstly and then decreased with the mass ratio of PEI and DA increased, and reached the maximum at a mass ratio of 1∶1. The deposition rate increased linearly with the time prolonged, which respectively reached 1.33% and 0.5% after 10 h for PEI/DA co-deposited system and pure DA-deposited that. The deposition rate had no obvious effect on the content of N element and activity recovery of immobilized CA. For enzyme immobilization, there was a saturated addition amount of the carrier which was 0.25 g PEI/PDA-SiO2/mg CA, and the optimal concentration of CA and GA was 0.8 mg/ml and 0.1%(mass), respectively. Under these conditions, the activity recovery of CA-PEI/PDA-SiO2 was about 78.8%. After 30 days of storage at 25℃, the remaining activity of immobilized CA was 77.2% while that of free CA was only 12%. The relative activity of immobilized CA was 88.3% after undergoing 10 cycles.关键词
聚乙烯亚胺/多巴胺/二氧化硅/酶/固定化/生物技术Key words
polyethylenimine/dopamine/silica/enzyme/immobilization/biotechnology分类
化学化工引用本文复制引用
王彩红,孙婧,季书馨,王燕子,刘文芳..聚乙烯亚胺/多巴胺改性氧化硅固定碳酸酐酶[J].化工学报,2019,70(5):1887-1893,7.基金项目
北京市自然科学基金项目(2172050) （2172050）
