title: A biosensor for the detection of triazine and phenylurea herbicides designed using Photosystem II coupled to a screen-printed electrode.
abstract: A biosensor for the detection of triazine- and phenylurea-type herbicides was constructed using isolated Photosystem II (PS II) complexes as a biosensing element. PSII isolated from the thermophilic cyanobacterium Synechococcus elongatus was immobilized on the surface of a screen-printed sensor composed of a graphite working electrode and Ag/AgCl reference electrode deposited on a polymeric substrate. The biosensor was mounted in a flow microcell with illumination. The principle of the detection was based on the fact that herbicides selectively block PSII electron transport activity in a concentration-dependent manner. Changes of the activity were registered amperometrically as the rate of photoreduction of an artificial electron acceptor. The setup resulted in a reusable herbicide biosensor with a good stability (half-life of 24 h) and limit of detection of approximately 10(-9) M for diuron, atrazine and simazine.
authors.affiliation: Photosynthesis Research Center, Institute of Microbiology, 379 81 Trebon, Czech Republic. koblizek@alga.cz
authors.forename: Michal
authors.initials: M
authors.lastname: Koblízek
authors.forename: Jan
authors.initials: J
authors.lastname: Malý
authors.forename: Jirí
authors.initials: J
authors.lastname: Masojídek
authors.forename: Josef
authors.initials: J
authors.lastname: Komenda
authors.forename: Tomás
authors.initials: T
authors.lastname: Kucera
authors.forename: Maria T
authors.initials: MT
authors.lastname: Giardi
authors.forename: Autar K
authors.initials: AK
authors.lastname: Mattoo
authors.forename: Roberto
authors.initials: R
authors.lastname: Pilloton
mesh_terms: D015374:Biosensing Techniques / Q000295:instrumentation* / Q000379:methods*; D002853:Chromatography, Liquid / Q000295:instrumentation / Q000379:methods; D000458:Cyanobacteria / Q000737:chemistry / Q000502:physiology; D004566:Electrodes; D006540:Herbicides / Q000032:analysis*; D010671:Phenylurea Compounds / Q000032:analysis*; D045322:Photosynthetic Reaction Center Complex Proteins / Q000378:metabolism; D045332:Photosystem II Protein Complex; D014227:Triazines
chemical_list: D006540:Herbicides; D010671:Phenylurea Compounds; D045322:Photosynthetic Reaction Center Complex Proteins; D045332:Photosystem II Protein Complex; D014227:Triazines