Various applications of immobilized glucose oxidase and polyphenol oxidase in a conducting polymer matrix

Cil, M.
Boyukbayram, A. E.
Kiralp, S.
Toppare, Levent Kamil
Yagci, Y.
In this study, glucose oxidase and polyphenol oxidase were immobilized in conducting polymer matrices; polypyrrole and poly(N-(4-(3-thienyl methylene)-oxycarbonyl phenyl) maleimide-co-pyrrole) via electrochemical method. Fourier transform infrared and scanning electron microscope were employed to characterize the copolymer of (N-(4-(3-thienyl methylene)-oxycarbonyl phenyl) maleimide) with pyrrole. Kinetic parameters, maximum reaction rate and Michealis-Menten constant, were determined. Effects of temperature and pH were examined for immobilized enzymes. Also, storage and operational stabilities of enzyme electrodes were investigated. Glucose and polyphenol oxidase enzyme electrodes were used for determination of the glucose amount in orange juices and human serum and phenolic amount in red wines, respectively.


An alternative supporting electrolyte for enzyme immobilization in conducting polymers
Kiralp, Senem; Balik, Balam; KARATAŞ, SEVİM; Toppare, Levent Kamil; Gungorb, Atilla (Elsevier BV, 2008-03-01)
In this study an alternative supporting electrolyte was used in enzyme immobilization. Invertase was studied to observe the effect of the supporting electrolyte. Sulfonated poly(arylene ether sulfone) was used as the supporting electrolyte during the electrolysis of pyrrole. The results show that the polymeric supporting electrolyte can be used instead of sodium dodecyl sulfate.
Structural properties of an engineered outer membrane protein G mutant, OmpG-16SL, investigated with infrared spectroscopy
Yilmaz, Irem; Yildiz, Ozkan; KORKMAZ ÖZKAN, FİLİZ (Informa UK Limited, 2019-05-31)
The structural and functional differences between wild type (WT) outer membrane protein G and its two mutants are investigated with Fourier transform infrared spectroscopy. Both mutants have a long extension to the primary sequence to increase the number of beta-strands from 14 (wild type) to 16 in an attempt to enlarge the pore diameter. The comparison among proteins is made in terms of pH-dependent conformational changes and thermal stability. Results show that all proteins respond to pH change but at dif...
Immobilization of glucose oxidase in conducting graft copolymers and determination of glucose amount in orange juices with enzyme electrodes
Yildiz, HB; Kiralp, S; Toppare, Levent Kamil; Yagci, Y (Elsevier BV, 2005-12-15)
Glucose oxidase was immobilized in conducting copolymers of three different types of poly(methyl methacrylate-co-thienyl methacrylate). Immobilization of enzyme was carried out by the entrapment in conducting polymers during electrochemical polymerization of pyrrole on the copolymer electrodes. Maximum reaction rate, Michaelis-Menten constants, temperature, pH and operational stabilities were determined for immobilized enzyme. The amount of glucose in orange juices of Turkey was investigated by using enzyme...
The effect of cysteine-43 mutation on thermostability and kinetic properties of citrate synthase from Thermoplasma acidophilum
Kocabıyık, Semra; Russel, RJM; Danson, MJ; Hough, DW (Elsevier BV, 1996-07-05)
In this study, we have substituted serine-43 by cysteine in the recombinant citrate synthase from a moderately thermophilic Archaeon Thermoplasma acidophilum, for site-specific attachment of labels and have investigated the effects of this mutation on the biochemical properties and thermal stability of the enzyme. Both wild-type and the mutant enzymes were purified to homogenity using affinity chromatography on Matrex Gel Red A. The mutant Thermoplasma citrate synthase is very similar to wild-type citrate s...
An amperometric acetylcholine biosensor based on a conducting polymer
Kanik, Fulya Ekiz; Kolb, Marit; TİMUR, SUNA; Bahadir, Muefit; Toppare, Levent Kamil (Elsevier BV, 2013-08-01)
An amperometric acetylcholine biosensor was prepared by the generation of the conducting polymer poly(4-(2,5-di(thiophen-2-yl)-1H-pyrrol-1-yl)benzenamine) (poly(SNS-NH2)) on graphite electrodes. For pesticide detection, the enzymes acetylcholinesterase (AChE) and choline oxidase (ChO) were co-immobilized onto the conducting polymer poly(SNS-NH2) films using covalent binding technique. Electrochemical polymerization was carried out using a three-electrode cell configuration via cyclic voltammetry. Characteri...
Citation Formats
M. Cil, A. E. Boyukbayram, S. Kiralp, L. K. Toppare, and Y. Yagci, “Various applications of immobilized glucose oxidase and polyphenol oxidase in a conducting polymer matrix,” INTERNATIONAL JOURNAL OF BIOLOGICAL MACROMOLECULES, pp. 49–55, 2007, Accessed: 00, 2020. [Online]. Available: