Construction of an acetylcholinesterase-choline oxidase biosensor for aldicarb determination

Kok, FN
Bozoglu, F
Hasırcı, Vasıf Nejat
In this study, acetylcholinesterase and choline oxidase were co-immobilized on poly(2-hydroxyethyl methacrylate) membranes and the change in oxygen consumption upon aldicarb introduction was measured. Immobilization of the enzymes was achieved either by entrapment or by surface attachment via a hybrid immobilization method including epichlorohydrin and Cibacron Blue F36A activation. Immobilized enzymes had a long-storage stability (only 15% activity decrease in 2 months in wet storage and no activity loss in dry storage). Aldicarb detection studies showed that a linear working range of 10-500 and 10-250 ppb aldicarb could be achieved by entrapped and surface immobilized enzymes, respectively. Enzymes immobilized on membrane surfaces responded to aldicarb presence more quickly than entrapped enzymes. Aldicarb concentrations as low as 23 and 12 ppb could be detected by entrapped and surface immobilized enzymes, respectively, in 25 min.


Determination of binary pesticide mixtures by an acetylcholinesterase-choline oxidase biosensor
Kok, FN; Hasırcı, Vasıf Nejat (2004-02-15)
In this study, acetylcholinesterase (AChE) and choline oxidase (ChO) were co-immobilized on poly (2-hydroxyethyl methacrylate) (pHEMA) membranes to construct a biosensor for the detection of anti-cholinesterase compounds. pHEMA membranes were prepared with the addition of SnCl4 to achieve the desired porosity. Immobilization of the enzymes was done by surface attachment via epichlorohydrin (Epi) and Cibacron Blue F3G-A (CB) activation. Enzyme immobilized membrane was used in the detection of anti-cholineste...
Synthesis of topoisomerase inhibitor type anticancer drugs linked gold nanoparticles
Pekçağlıyan, Gönül; Demir, Ayhan Sıtkı; Department of Chemistry (2008)
This study presents studies on camptothecin (CPT), a potent antitumor agent in order to improve its stability and solubility without reducing its activity. The work describes the modification of camptothecin at 20-OH position a new strategy to overcome the stability and solubility problems of the free drug. Camptothecin is conneted to linker that could be processed to a terminal thiol group and this thiol group was connected to gold surface, to obtain CPT-gold nanoparticles. In the first part of the study; ...
Application of silicalite-modified electrode for the development of sucrose biosensor with improved characteristics
Pyeshkova, Viktoriya M.; Dudchenko, Oleksandr Y.; Soldatkin, Oleksandr O.; Kasap, Berna Ozansoy; Lagarde, Florence; Akata Kurç, Burcu; Dzyadevych, Sergei V. (2015-03-27)
The application of silicalite for improvement of working characteristics of conductometric enzyme biosensors for determination of sucrose was studied in this research. Biosensors based on different types of silicalite-modified electrodes were studied and compared according to their analytical characteristics. Polyethylenimine/glutaraldehyde/silicalite-modified biosensors showed higher sensitivity compared with others type of biosensors. Moreover, the polyethylenimine/glutaraldehyde/silicalite sucrose biosen...
Investigation of the performance of colloidal LiFePO4 particles in suspension flow battery
Yıldız, Bayram; Aşkar, Yasemin; Coşkun, Elif; Maviş, Bora; Çınar, Simge (2021-06-12)
In this study, colloidal LiFePO4 particles were synthesized through solvothermal route. Effect of solvothermal method parameters on formation of colloidal LiFePO4 was investigated. Post-processing treatments were found effective to obtain non-aggregated colloidal particles. The rheological behavior of aqueous suspensions including electroactive material was examined in terms of salt, electroactive material concentration and carbon content. A three-electrode systems was used to analyze electrochemical perfor...
Investigation of adsorption of pesticides by organo-zeolite from wastewater
Lüle, Güzide Meltem; Atalay, M Ümit; Özbayoğlu, Gülhan; Department of Mining Engineering (2011)
The aim of this study was to determine the adsorption capacity of activated carbon and organo-zeolites for removal of pesticides in water. In order to prepare organo-zeolite, two kinds of cationic surfactants, namely, hexadecyltrimethyl ammonium bromide (HTAB) and dodecyltrimethyl ammonium bromide (DTAB) were used. Adsorption studies of cationic surfactant on zeolite were investigated in respect to initial concentration of cationic surfactant, time, and temperature. It has been found that the best fitted is...
Citation Formats
F. Kok, F. Bozoglu, and V. N. Hasırcı, “Construction of an acetylcholinesterase-choline oxidase biosensor for aldicarb determination,” BIOSENSORS & BIOELECTRONICS, pp. 531–539, 2002, Accessed: 00, 2020. [Online]. Available: