Semi-interpenetrating polymer networks (IPNs) for entrapment of glucose isomerase

Demirel, G
Ozcetin, G
Sahin, F
Tumturk, H
Aksoy, S
Hasırcı, Nesrin
Glucose isomerase (GI) was entrapped in three different hydrogels such as poly(acrylamide), semi-interpenctrating poly(acrylamide)/K-carrageenan, and poly(acrylamide)/alginate polymer networks. The values for pH optimum and temperature for free and immobilized glucose isomerase were found to be the same as 7.5 and 60 degrees C, respectively. The K-m values for free and immobilized enzyme in poly(acrylamide), poly(acrylamide)/K-carrageenan and poly(acrylamide)/alginate matrices were determined as 18.87, 1.22, 2.78, and 4.54 mg/mL, respectively, while the V-max values for the same systems calculated as 2.51, 0.63, 0.72, and 0.82 mg/mL min, respectively. The storage stability values of immobilized enzyme systems were observed as 81%. 33% and 32%, respectively, after 42 days. In addition to this, it was observed that, after 25th use in 5 days, the retained activities for immobilized enzyme in poly(acrylamide), and semi-interpenetrating polymer networks of poly(acrylamide)/K-carrageenan and poly(acrylamide)/alginate matrices were found as 98%, 71% and 72%, respectively.


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Böyükbayram, Ayşe Elif; Toppare, Levent Kamil; Department of Chemistry (2005)
Immobilization of invertase, polyphenol oxidase (PPO) and glucose oxidase (GOD) enzymes were performed in electrochemically synthesized two types of conducting copolymers. One end and two end thiophene-capped polytetrahydrofuran (TPTHF-1 and TPTHF-2) were copolymerized with pyrrole under conditions of constant potential electrolysis. The copolymers were characterized by thermal, spectroscopic and scanning electron microscopy analyses. Immobilization was carried out via entrapment of enzymes in two types of ...
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Angardi, Vahideh; Çalık, Pınar; Department of Chemical Engineering (2011)
In this study, process development for glucose isomerase (GI) was aimed. In this context, firstly, thermostable xyl genes, PCR amplified from Thermus thermophilus and Pyrococcus furiosus cells, were recombined to the E.coli BL21 (DE3) and P.pastoris strains, respectively. But significant increase in the term of GI activity compared with wild type cells only detected in recombinant E.coli strain so this strain was selected for further experiments. Then, the effect of different natural and artificial inducers...
Semi-interpenetrating polymer networks (semi-IPNs) for entrapment of laccase and their use in Acid Orange 52 decolorization
Yamak, Ozgur; KALKAN, NİGAR; AKSOY, SERPİL; ALTINOK, HAYDAR; Hasırcı, Nesrin (2009-04-01)
Laccase enzyme (L) from Trametes versicolor was entrapped in three hydrogel structures namely poly(acrylamide-N-isopropylacrylamide), P(AAm-NIPA), and semi-interpenetrating networks of poly(-acrylamide)/alginate, P(AAm)/Alg, and poly(acrylamide-N-isopropylacrylamide)/alginate, P(AAm-NIPA)/Alg. The optimum temperatures for free and all immobilized systems were found to be 40 degrees C. For free and immobilized laccase systems of P(AAm-NIPA)-L, P(AAm)/Alg-L and P(AAm-NIPA)/Alg-L, K-m values were found to be 6...
Immobilization of invertase and glucose oxidase in conducting H-type polysiloxane/polypyrrole block copolymers
Gursel, A; Alkan, S; Toppare, Levent Kamil; Yagci, Y (Elsevier BV, 2003-01-01)
In this study, immobilizations of enzymes, invertase and glucose oxidase, were achieved in conducting copolymers of N-pyrrolyl terminated polydimethylsiloxane/polypyrrole (PDMS/PPy) matrices via electrochemical polymerization. The kinetic parameters, v(max) (maximum reaction rate) and K-m (substrate affinity), of both free and immobilized enzymes were determined. The effect of supporting electrolytes, p-toluene sulfonic acid and sodium dodecyl sulfate, on enzyme activity and film morphologies was examined. ...
ARICA, MY; Hasırcı, Vasıf Nejat (1993-09-01)
Glucose oxidase was immobilized onto poly(2-hydroxyethyl methacrylate) membranes by covalent bonding through epichlorohydrin. The highest immobilization efficiency was found to be 17.4%. The K(m) values were 5.9 and 8.8 mm for free and bound enzymes, respectively, and the V(max) values were 0.071 and 0.067 mm/min for free and bound enzymes. When the medium was saturated with oxygen K(m) was not altered significantly but V(max) was. The optimum pHs for the free and bound enzyme were determined to be 5 and 6,...
Citation Formats
G. Demirel, G. Ozcetin, F. Sahin, H. Tumturk, S. Aksoy, and N. Hasırcı, “Semi-interpenetrating polymer networks (IPNs) for entrapment of glucose isomerase,” REACTIVE & FUNCTIONAL POLYMERS, pp. 389–394, 2006, Accessed: 00, 2020. [Online]. Available: