Covalent immobilization of glucose isomerase on poly(methyl metachrylate-2-hydroxyethyl metachrylate) microbeads

ivCOVALENT IMMOBILIZATION OF GLUCOSE ISOMERASE ONPOLY(METHYL METACHRYLATE- 2-HYDROXYETHYLMETACHRYLATE) MICROBEADS(M.Sc. Thesis)Ersoy ŞAH NGAZ UNIVERSITYINSTITUTE OF SCIENCE AND TECHNOLOGYJanuary 2007ABSTRACTIn this study, glucose isomerase enzyme (GI) was covalentlyimmobilized on poly(methymetacrylate-2-hydroxyethylmethacrylate),P(MMA-HEMA) microbeads, which were activated by using cyanuricchloride (C3N3Cl3) and epichlorohydrin (C3H5ClO). Optimum pH wasdetermined as 7.5 and 8.0, for free GI, cyanuric chloride immobilizedglucose isomerase (CC-IGI), epichlorohydrin immobilized glucoseisomerase (ECH-IGI) respectively. Optimum temperature waso odetermined as 60 C and 65 C for free GI, cyanuric chlorideimmobilized glucose isomerase (CC-IGI), epichlorohydrin immobilizedglucose isomerase (ECH-IGI) respectively. Km values were found to be6.50x10-5 mol/L, 1.26x10-4 mol/L, 2.55x10-4 mol/L, Vmak values 2.42x10-5mol/L.dak, 4.18x10-5 mol/L.dak, 3.46x10-5 mol/L.dak for free GI, CC-IGIand ECH-IGI, respectively. After 56 days of storage at 4 oC, free GI, CC-IGI and ECH-IGI retained %48.3, %57.1 and %59.4 of their originalactivities, respectively. CC-IGI and ECH-IGI were retained %73.6 and%78.8 of their initial activities under continuous flow column after 110min, respectively.vInactivation rate constans (ki) of free, CC-IGI and ECH-IGI werecalculated as 8,0x10-3 min-1, 5,5x10-3 min-1, 6,0x10-3 min-1 at 70° theyC,were also calculated as 1,0x10-2 min-1, 8,0x10-3 min-1, 7,0x10-3 min-1respectively at 80ºC.Science Code : 201.1.117Key Words : poly(methyl metachrylate-2-hydroxyethyl metachrylate)covalent binding, immobilization, glucose isomerasePage Number : 95Adviser : Prof. Dr. Serpil AKSOY