L-Dopa Synthesis on Conducting Polymers

Erdogan, Huriye
Tuncagil, Sevinc
Toppare, Levent Kamil
With regards to the synthesis of L-Dopa (l-3,4-dihydroxy phenylalanine) two types of biosensors were designed by immobilizing tyrosinase on conducting polymers; polypyrrole (PPy) and poly(3,4-ethylenedioxythiophene) (PEDOT). PPy and PEDOT were synthesized electrochemically and tyrosinase immobilized by entrapment during electropolymerization. The kinetic parameters of the designed biosensors, maximum reaction rate of the enzyme (Vmax) and Michaelis Menten constant (Km) were determined. Vmax were found as 0.013 for PPy matrix and 0.041 mol/min.electrode for PEDOT matrix. Km values were determined as 3.7 and 5.2mM for PPy and PEDOT matrices respectively. Calibration curves for enzyme activity vs. substrate concentration were drawn for the range of 0.8 to 2.5 mM L-Tyrosine. Optimum temperature and pH, operational and shelf life stabilities of immobilized enzyme were also examined.


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In this study, a novel donor-acceptor type monomer was designed based on selenophene and benzotriazole with a bulky pendant group and synthesized through Stille coupling reaction. The monomer was polymerized electrochemically by using cyclic voltammetry and also chemically by oxidation in the presence of FeCl3. Both polymers were then compared in terms of their optical properties, electrochemical and spectroelectrochemical behaviors, kinetic and colorimetric properties and surface morphologies. Independent ...
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Karatas, Y; Toppare, Levent Kamil; Tincer, T (Informa UK Limited, 2003-01-01)
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Camurlu, P; Toppare, Levent Kamil (Informa UK Limited, 2006-03-01)
In this study, dual type polymer electrochromic devices (ECDs) based on homopolymer and copolymer of hexanedioic acid bis-(2-thiophen-3-yl-ethyl ester) with 3,4-ethylene dioxythiophene (EDOT) were constructed, where PEDOT functioned as the cathodically coloring layer. Spectroelectrochemistry, switching ability, stability, open circuit memory and color of the devices were investigated. Results of the kinetic studies showed these devices exhibit switching times around 1.8 s with an optical contrast of 24-25.3...
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Synthesis and Characterization of 2-Hydroxyethyl Methacrylate (HEMA) and Methyl Methacrylate (MMA) Copolymer Used as Biomaterial
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A series of poly(methyl methacrylate-co-hydroxyethyl methacrylate) (PMMA-co-PHEMA), copolymers were synthesized by an emulsion polymerization technique. Copolymer compositions were determined by FT-IR and 1H-NMR spectroscopy. It was found that comonomer ratios used in the recipes were comparable within the actual copolymers. Glass transition temperatures (Tg) of PMMA-co-PHEMA copolymers were varied from 119 degrees C to 100 degrees C by increasing HEMA content. Thermogravimetric analysis showed that the cop...
Citation Formats
H. Erdogan, S. Tuncagil, and L. K. Toppare, “L-Dopa Synthesis on Conducting Polymers,” JOURNAL OF MACROMOLECULAR SCIENCE PART A-PURE AND APPLIED CHEMISTRY, pp. 209–214, 2010, Accessed: 00, 2020. [Online]. Available: https://hdl.handle.net/11511/36674.