title: Amperometric sulfide detection using Coprinus cinereus peroxidase immobilized on screen printed electrode in an enzyme inhibition based biosensor.
abstract: In the present work, an amperometric inhibition biosensor for the determination of sulfide has been fabricated by immobilizing Coprinus cinereus peroxidase (CIP) on the surface of screen printed electrode (SPE). Chitosan/acrylamide was applied for immobilization of peroxidase on the working electrode. The amperometric measurement was performed at an applied potential of -150 mV versus Ag/AgCl with a scan rate of 100 mV in the presence of hydroquinone as electron mediator and 0.1M phosphate buffer solution of pH 6.5. The variables influencing the performance of sensor including the amount of substrate, mediator concentration and electrolyte pH were optimized. The determination of sulfide can be achieved in a linear range of 1.09-16.3 μM with a detection limit of 0.3 μM. Developed sensor showed quicker response to sulfide compared to the previous developed sulfide biosensors. Common anions and cations in environmental water did not interfere with sulfide detection by the developed biosensor. Cyanide interference on the enzyme inhibition caused 43.25% error in the calibration assay which is less than the amounts reported by previous studies. Because of high sensitivity and the low-cost of SPE, this inhibition biosensor can be successfully used for analysis of environmental water samples.
authors.affiliation: Department of Chemical and Petroleum Engineering, Sharif University of Technology, P.O. Box 11155-9465, Azadi Ave., Tehran, Iran.
authors.forename: Iman Shahidi Pour
authors.initials: ISP
authors.lastname: Savizi
authors.affiliation: Department of Chemical and Petroleum Engineering, Sharif University of Technology, P.O. Box 11155-9465, Azadi Ave., Tehran, Iran. Electronic address: kariminia@sharif.ir.
authors.forename: Hamid-Reza
authors.initials: HR
authors.lastname: Kariminia
authors.affiliation: Department of Chemical and Petroleum Engineering, Sharif University of Technology, P.O. Box 11155-9465, Azadi Ave., Tehran, Iran.
authors.forename: Mohammad
authors.initials: M
authors.lastname: Ghadiri
authors.affiliation: Department of Chemical and Petroleum Engineering, Sharif University of Technology, P.O. Box 11155-9465, Azadi Ave., Tehran, Iran.
authors.forename: Reza
authors.initials: R
authors.lastname: Roosta-Azad
mesh_terms: D015374:Biosensing Techniques / Q000379:methods* / Q000706:statistics & numerical data; D003302:Coprinus / Q000201:enzymology; D055664:Electrochemical Techniques; D004566:Electrodes; D004800:Enzymes, Immobilized; D005656:Fungal Proteins; D006861:Hydrogen Peroxide; D006863:Hydrogen-Ion Concentration; D006873:Hydroquinones; D010544:Peroxidases; D015203:Reproducibility of Results; D013440:Sulfides / Q000032:analysis*; D014874:Water Pollutants, Chemical / Q000032:analysis*
chemical_list: D004800:Enzymes, Immobilized; D005656:Fungal Proteins; D006873:Hydroquinones; D013440:Sulfides; D014874:Water Pollutants, Chemical; D006861:Hydrogen Peroxide; D010544:Peroxidases; C031927:hydroquinone