A palladium complex mediated laccase biosensor and sensitive voltammetric analysis of catechol
Makaleler > Tam Makale · 2014
Yazarlar: Erol Akyilmaz, Başak Şahin, Hayati TÜRKMEN
Sensor Letters, SCI Expanded İndekslerine Giren Dergi, Uluslararası, 2014, cilt 12, ss 1519-1525
DOI: 10.1166/sl.2014.3346
Özet
In this study, an amperometric laccase biosensor which detects catechol was developed in order to investigate the usage of water soluble palladium(II) complexes bearing (NHC/TPPTS) ligands (NHC: benzimidazol-2-ylidene; TPPTS: triphenylphosphine-3,3',3"-trisulfonic acid trisodium salt) "RC-72" as a mediator. In the construction of the biosensor laccase was immobilized by formation of selfassembled monolayer (SAM) by using cysteamine and cross-linking agent glutaraldehyde on a gold working electrode. The phosphate buffer (50 mM, pH 7.0) and 30 °C were established as providing the optimum working conditions. Some optimization and characterization studies such as enzyme amount, duration of SAM formation, glutaraldehyde percentage for cross-linking procedure, buffer solution, repetability of the biosensor were carried out. Using both amperometric and differential pulse (DP) methods, the biosensor shows a linear response related to the concentration of catechol in the range from 10 to 100 μM with a response time of 2 sec. The corresponding detection limit is 4.76 μM for amperometric and 5.08 μM for DP method based on signal to noise ratios (S/N) ≥3 under the optimized working conditions.