title: Measuring hydrogen peroxide due to water radiolysis using a modified horseradish peroxidase based biosensor as an alternative dosimetry method.
abstract: H2O2 generated during water radiolysis was measured electrochemically as an alternative dosimetry method. A biosensor was fabricated by immobilising modified horseradish peroxidase (HRP) on a glassy carbon electrode (GCE) followed by evaluation of its analytical parameters. Anthraquinone 2-carboxylic acid was used to modify HRP. To assess sensor performance, phosphate buffer solutions were irradiated with 0.510 Gy of gamma ray emitted from (60)Co. The results showed that this sensor can detect low quantities of hydrogen peroxide in water radiolysis. Sensitivity, detection limit and linear range of the biosensor were 260 nA/Gy, 0.392 Gy and 0.5-5 Gy, respectively. Long term stability studies showed that sensor responses were stable for at least a month. The cathodic peak current, as biosensor response, subsequently decreased to 20% of its initial value.
authors.affiliation: Neuroscience Research Center, Baqiyatallah University of Medical Sciences, Tehran, Iran; Department of Physiology and Biophysics, Baqiyatallah University of Medical Sciences, Tehran, Iran. Electronic address: tavakoli@ibb.ut.ac.ir.
authors.forename: Hassan
authors.initials: H
authors.lastname: Tavakoli
authors.affiliation: Neuroscience Research Center, Baqiyatallah University of Medical Sciences, Tehran, Iran.
authors.forename: Amin Azam
authors.initials: AA
authors.lastname: Baghbanan
mesh_terms: D000880:Anthraquinones / Q000737:chemistry; D015374:Biosensing Techniques / Q000295:instrumentation / Q000379:methods*; D002244:Carbon / Q000737:chemistry; D002264:Carboxylic Acids / Q000737:chemistry; D004563:Electrochemistry; D004566:Electrodes; D004800:Enzymes, Immobilized / Q000737:chemistry / Q000378:metabolism; D005898:Glass / Q000737:chemistry; D006735:Horseradish Peroxidase / Q000737:chemistry* / Q000378:metabolism; D006861:Hydrogen Peroxide / Q000032:analysis* / Q000737:chemistry*; D057230:Limit of Detection; D011874:Radiometry / Q000295:instrumentation / Q000379:methods*; D014867:Water / Q000737:chemistry*
chemical_list: D000880:Anthraquinones; D002264:Carboxylic Acids; D004800:Enzymes, Immobilized; D014867:Water; D002244:Carbon; D006861:Hydrogen Peroxide; D006735:Horseradish Peroxidase
keywords: Dosimetry; Hydrogen peroxide; Ionising radiation; Modified horseradish peroxidase; Water radiolysis