title: Assessment of the enzymatic activity and inhibition using HPFA with a microreactor, trypsin, absorbed on immobilized artificial membrane.
abstract: The purpose of this study was to develop a new method to assess the activity and inhibition of the immobilized enzyme trypsin based on the frontal analysis of enzymatic reaction products. This novel technique was performed by on-line monitoring of the absorption at 253 nm of N-benzoyl-L-arginine (BA) from the hydrolysis of N-benzoyl-L-arginine ethyl ester (BAEE). A microreactor was constructed by immobilizing trypsin on an immobilized artificial membrane (IAM)-packed column. Trypsin was non-covalently and dynamically immobilized on-line in the hydrophobic interface of an IAM liquid chromatographic stationary phase. The trypsin-IAM stationary phase was bioactive. Due to the enzymatic reaction, the substrate of BAEE was completely hydrolyzed when the BAEE concentration was below 0.5 mmol/L and partly hydrolyzed when the BAEE concentration ranged from 0.75 to 1.0 mmol/L. By the addition of soybean trypsin inhibitor (STI), phenylmethane sulfonyl fluoride (PMSF), and benzamidine into the substrate solution, the results obtained from the frontal analysis showed that the activity of trypsin on IAM was strongly inhibited not only by STI but by both benzamidine and PMSF.
authors.affiliation: School of Life Science and Technology, Beijing Institute of Technology, Beijing 100081, China.
authors.forename: Yueying
authors.initials: Y
authors.lastname: Liu
authors.forename: Lili
authors.initials: L
authors.lastname: Li
authors.forename: Rongji
authors.initials: R
authors.lastname: Dai
authors.forename: Feng
authors.initials: F
authors.lastname: Qu
authors.forename: Lina
authors.initials: L
authors.lastname: Geng
authors.forename: Xin-Min
authors.initials: XM
authors.lastname: Li
authors.forename: Yulin
authors.initials: Y
authors.lastname: Deng
mesh_terms: D001120:Arginine / Q000031:analogs & derivatives / Q000737:chemistry; D001550:Benzamidines / Q000494:pharmacology; D002845:Chromatography / Q000379:methods*; D004800:Enzymes, Immobilized / Q000737:chemistry*; D008567:Membranes, Artificial; D014105:Tosyl Compounds / Q000494:pharmacology; D014357:Trypsin / Q000737:chemistry*; D014361:Trypsin Inhibitors / Q000494:pharmacology
chemical_list: D001550:Benzamidines; D004800:Enzymes, Immobilized; D008567:Membranes, Artificial; D014105:Tosyl Compounds; D014361:Trypsin Inhibitors; C003614:4-toluenesulfonyl fluoride; D001120:Arginine; C009727:benzoylarginine ethyl ester; D014357:Trypsin; C032157:benzamidine