A biosensor for the detection of triazine and phenylurea herbicides designed using Photosystem II coupled to a screen-printed electrode.
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.
Koblízek
Michal
M
Photosynthesis Research Center, Institute of Microbiology, 379 81 Trebon, Czech Republic. koblizek@alga.cz
Malý
Jan
J
Masojídek
Jirí
J
Komenda
Josef
J
Kucera
Tomás
T
Giardi
Maria T
MT
Mattoo
Autar K
AK
Pilloton
Roberto
R
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
D006540:Herbicides; D010671:Phenylurea Compounds; D045322:Photosynthetic Reaction Center Complex Proteins; D045332:Photosystem II Protein Complex; D014227:Triazines