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

2006-04-01
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.
REACTIVE & FUNCTIONAL POLYMERS

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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: https://hdl.handle.net/11511/29885.