Amperometric cholesterol and alcohol biosensors based on conducting polymers

Türkarslan, Özlem
Cholesterol and ethanol biosensors based on conducting polypyrrole (PPy), poly(3,4-ethylenedioxythiophene) (PEDOT) and poly(3,4-ethylenedioxypyrrole) (PEDOP) were constructed. Cholesterol oxidase (ChOx, from Pseudomonas fluorescens) and alcohol oxidase (AlcOx, from Pichia pastoris) were physically entrapped during electropolymerization of the monomers (Py, EDOT, EDOP) in phosphate buffer containing sodium dodecylsulfate (SDS) as the supporting electrolyte. The amperometric responses of the enzyme electrodes were measured monitoring oxidation current of H2O2 at +0.7 V in the absence of a mediator. Kinetic parameters, such as Km and Imax, operational and storage stabilities, effects of pH and temperature were determined for all entrapment supports. Based on Michaelis-Menten (Km) constants, it can be interpreted that both enzymes immobilized in PEDOT showed the highest affinities towards their substrates. Before testing the alcohol biosensors on alcoholic beverages, effects of interferents (glucose, acetic acid, citric acid, L-ascorbic acid) which might be present in beverages were determined. The alcohol content of the distilled beverages (vodka, dry cin, whisky, rakı) was measured with these biosensors. A good match with the chromatography results (done by the companies) was observed.


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In this research, diazophenylene and diazodiphenylene bridged metal-phthalocyanine polymers were produced from diazonium salt of diaminophenylene/bensidin and pre-synthesized tetraamino metal phthalocyanines. Tetraamino metal phthalocyanine complexes of Co, Ni, Cu, Ce, and Er were obtained by reducing tetranitro metal phthalocyanine complexes synthesized from 3-nitrophthalic anhydride, urea, metal salt, and ammonium molybdate catalyst. Complexes and polymers were characterized by Fourier Transform Infrared ...
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Çelik, Güler Bayraklı; Kısakürek, Duygu; Department of Chemistry (2007)
Microwave-assisted novel synthesis of poly(dibromophenylene oxide) or poly(diiodophenylene oxide) (P), conducting polymer (CP) and/or crosslinked polymer (CLP) and/or radical ion polymer (RIP) were achieved simultaneously from lithium, sodium or potassium 2,4,6-bromophenolate or sodium 2,4,6-iodophenolate in a very short time interval. Polymerizations were carried out by constant microwave energy with different time intervals varying from 1 to 20 min; or at constant time intervals with variation of microwav...
Citation Formats
Ö. Türkarslan, “Amperometric cholesterol and alcohol biosensors based on conducting polymers,” Ph.D. - Doctoral Program, Middle East Technical University, 2010.