On-line synthesis utilizing immobilized enzyme reactors based upon immobilized dopamine beta-hydroxylase

The covalent immobilization of microsomal uridine diphospho-glucuronosyltransferase (UDPGT): Initial synthesis and characterization of an UDPGT immobilized enzyme reactor for the on-line study of glucuronidation

“…As observed with the K m values, the calculated differences were less than a three-fold difference and suggest that although there was a difference in the V max values, the immobilization did not significantly affect the activity of the UDPGT. This trend has been previously observed with other IMER systems [22][23][24]. The differences in the calculated V max values may be due to the experimental format.…”

Silica-Immobilized Enzyme Reactors

“…[80] The work of Markoglou and Wainer has demonstrated the application of IMER systems for the analysis of catecholamines in order to understand the physiological interaction with various adrenergic receptor proteins. [81][82][83][84][85] Dopamine β-hydroxylase (DBH) and phenylethanolamine N-methyltransferase (PNMT) are essential enzymes involved in the metabolism of catecholamines in vivo. These enzymes are essential to nervous signaling and implicated in neurological disorders such as Schizophrenia and Parkinson's disease.…”

“…The technology was extended to incorporate two different forms of DBH (soluble and membrane-bound) by utilizing two differing methods of IMER preparation; an immobilized artificial membrane for the membrane-bound protein and glutaraldehyde-functionalized silica for the soluble protein. [85] Screening for prodrug activation Berne et al describe an IMER containing a bacterial nitrobenzene nitroreductase enzyme that catalyzes the conversion of a nitro group to hydroxylamine resulting in a large electronic change which can be exploited for a variety of biotechnological applications; primarily the activation of prodrugs and proantibiotics for cancer treatments or antibiotic therapy, respectively. [87] Nitrobenzene nitroreductase was immobilized (>80% immobilization efficiency) in a silica matrix formed by polyethyleneimine (PEI) that catalyzes the formation of a matrix of interconnected silica particles of ~1 µm diameter.…”

Monolithic micro-immobilized-enzyme reactor with human recombinant acetylcholinesterase for on-line inhibition studies

“…Immobilization procedures have been found appropriate to covalently bind enzymes to modified silica matrices, with retention of enzymatic activity [1][2][3][4][5][6][7]. The inclusion of immobilized enzymes on a solid support in a chromatographic column has allowed preserving the enzymatic activity from inactivating processes, widely increasing the enzyme stability, with advantages in term of accuracy and reproducibility [8][9][10][11][12][13][14][15].…”