Characterization and potential applications of immobilized glucose oxidase and polyphenol oxidase

Ekinci, Olcun
Boyukbayram, A. Elif
Kiralp, Senem
Toppare, Levent Kamil
Yagci, Yusuf
Pyrrole functionalized polystyrene (PStPy) was copolymerized with pyrrole to obtain a conducting copolymer, P(PStPy-co-Py) which is used as the immobilization matrix. Glucose oxidase and polyphenol oxidase enzymes were immobilized via the entrapment method by electrochemical polymerization. Enzyme electrodes were prepared by electrolysis at a constant potential using sodium dodecyl sulfate (SDS) as the supporting electrolyte during the copolymerization of PStPy with pyrrole. Maximum reaction rates (V-max) and enzyme affinities (Michaelis-Menten constants, K-m) were determined for the enzyme entrapped both in polypyrrole (PPy) and P(PStPy-co-Py) matrices. Optimizations of enzyme electrodes were done by examining the effects of temperature and pH on enzymes' activities along with the shelf life and operational stability investigations. Glucose oxidase enzyme electrodes were used for human serum analysis and glucose determination in two brands of orange juices. Polyphenol oxidase enzyme electrodes were used for the determination of phenolics in red wines of Turkey.


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Terephthalic acid bis-(thiophen-3-yl-methyl thioester) (TTMT) was synthesized via the reaction of thiophen-3-yl methanethiol with terephthaloyl dichloride. Nuclear magnetic resonance ( H-1-NMR) spectroscopy and Fourier transform infrared (FTIR) spectroscopy were utilized for the characterization of the monomer. Electrochemical copolymerization of TTMT with thiophene in acetonitrile/boron trifluoride diethyl etherate (AN/BFEE) (8:2, v/v) solvent mixture was realized by using tetrabutylammonium tetrafluorobor...
Comparison of Natural Halloysite With Synthetic Carbon Nanotubes in Poly(lactic acid) Based Composites
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The objective of this study is to compare the mechanical properties, structure and degradability of the nanocomposites prepared with tubular nanofillers, halloysite (HNT) and carbon nanotube (CNT) in poly(lactic acid) (PLA), and thermoplastic polyurethane (TPU) toughened PLA (T-PLA) matrices. In the PLA matrix, CNT increased, whereas HNT decreased the tensile strength with increasing filler content. Also, the elongation at break and impact strength decreased with increasing CNT content, but these properties...
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Citation Formats
O. Ekinci, A. E. Boyukbayram, S. Kiralp, L. K. Toppare, and Y. Yagci, “Characterization and potential applications of immobilized glucose oxidase and polyphenol oxidase,” JOURNAL OF MACROMOLECULAR SCIENCE PART A-PURE AND APPLIED CHEMISTRY, pp. 801–808, 2007, Accessed: 00, 2020. [Online]. Available: