Senem Kiralp

Immobilization of polyphenol oxidase in conducting copolymers and determination of phenolic compounds in wines with enzyme electrodes

Polyphenol oxidase (PPO) was immobilized in copolymers of thiophene functionalized menthyl monomer (MM) with pyrrole. Immobilization of enzyme was performed via entrapment in conducting copolymers during electrochemical polymerization of pyrrole. Maximum reaction rates, Michaelis-Menten constants and temperature, pH and operational stabilities of enzyme electrodes were investigated. Total amount of phenolic compounds in red wines of Turkey were analyzed by using these electrodes.

Immobilization of invertase in copolymers of thiophene functionalized menthyl ester with pyrrole

Copolymers of thiophene functionalized menthyl monomer (MM) with pyrrole were used in immobilization of invertase. Michaelis-Menten constant and maximum reaction rates for immobilized invertase were investigated. Temperature optimization. operational stability and shelf-life of obtained enzyme electrodes were studied.

Determination of phenolic compounds in wines with enzyme electrodes fabricated by immobilization of polyphenol oxidase in conducting copolymers

A copolymer of pyrrole with a new monomer (MBTA) containing an ester group derived from 3-thiophene acetic acid and (S)-(-)-2-methylbutanol was used as the matrix for immobilization of polyphenol oxidase. Enzyme electrodes were constructed by entrapment of enzyme in the conducting copolymer during the electrochemical polymerization of pyrrole. The performance of enzyme electrodes was optimized by examining the effects of pH and temperature on enzyme activity. The changes in the maximum reaction rate (V max) and Michaelis-Menten constant (K m) upon immobilization were investigated in addition to shelf-life and operational stability. By using these enzyme electrodes the total amount of phenolic compounds in red wines of Turkey was also analyzed.

Synthesis and Characterization of Conducting Copolymers of Menthyl Ester of 3-Thiophene Acetic Acid with Pyrrole

A new thiophene derivative containing menthyl group (MM) was synthesized and polymerized via chemical and electrochemical (constant current) methods. Polymers obtained and MM itself were used to synthesize copolymers with pyrrole under conditions of constant potential electrolyses. Cyclic voltammetry (CV), thermal analysis (DSC, TGA) and scanning electron microscopy (SEM) analyses were performed for the characterization of samples.