An acetylcholinesterase biosensor based on a conducting polymer using multiwalled carbon nanotubes for amperometric detection of organophosphorous pesticides
By Kesik, Melis; Kanik, Fulya Ekiz; Turan, Janset; Kolb, Marit; Timur, Suna; Bahadir, Müfit & Toppare, Levent
Published in Sensors and Actuators B: Chemical
NULL
2014
Abstract
A novel amperometric biosensor based on a conducting polymer using multi walled carbon nanotube modified electrode was developed for detection of organophosphorus pesticides. Acetylcholinesterase (AChE) was successfully immobilized by covalent linkage on the modified graphite electrode. Carbon nanotubes were functionalized by electrochemical treatment. A conducting polymer; poly(4-(2,5-di(thiophen-2-yl)-1H-pyrrol-1-yl)benzenamine) (poly(SNS-NH2)) was synthesized via electropolymerization to examine its matrix properties for biomolecule immobilization. This strategy enhanced electron transfer rate at a lower potential (+100 mV vs. Ag reference) and catalyzed electrochemical oxidation of acetylthiocholine effectively. Scanning electron microscopy (SEM), X-ray photoelectron spectroscopy (XPS), contact angle measurements and electrochemical impedance spectroscopy (EIS), cyclic voltammetry (CV) techniques were used to monitor changes in surface morphologies and electrochemical characterizations. The proposed biosensor design offered a fast response time (6 s), a wide linear range (0.05 mM and 8.00 mM) and a low detection limit (0.09 mM) with a high sensitivity (24.16 μA mM-1 cm-2) for acetylthiocholine. The inhibition responses of paraoxon, parathion and chlorfenvinphos on the enzymatic activity of AChE were detected. The fabricated biosensor was tested for the detection of pesticides in fortified tap water samples. The results were found to be in good agreement with the ones determined by HPLC/DAD technique.
Microsoft is Ending Support for Windows 7
Microsoft will discontinue support for Windows 7 on January 14, 2020 which means Gamry will also be discontinuing support for Windows 7. If you are upgrading to Windows 10, like many companies and institutions, you need to be running Version 7 of our s oftware . Please note that only USB and Ethernet-based instruments can run in Version 7. Eligible users can download the latest version of our software through our online Client Portal .
If you haven't already registered your instrument, you can do so through the Client Portal .
Please email Technical Support if you have any questions regarding this transition. Please be sure to include your instrument model and serial number when contacting us.