title: A simple colorimetric enzymatic-assay for okadaic acid detection based on the immobilization of protein phosphatase 2A in sol-gel.
abstract: Okadaic acid (OA), a lipophilic toxin, is produced by Dinophysis and Prorocentrum, and causes diarrheic shellfish poisoning to humans. The mechanism of OA action is based on the reversible inhibition of protein phosphatase type 2A (PP2A) by the toxin. Therefore, this inhibition could be used to develop assay for OA detection. In this work, a colorimetric test based on the PP2A inhibition was developed for OA detection. PP2A from GTP and Millipore was immobilized on silica sol-gel, and the detection was performed. A limit of detection of 0.29 and 1.14 μg/L was respectively observed for enzyme from GTP and Millipore. The immobilization technique provided a tool to preserve the enzymatic activity, which is very unstable in solution. The PP2A immobilized sol-gel exhibited a storage stability of near 5 months, when microtiter plate with enzyme-immobilized polymer was kept at -18C°. The combination of the simplicity of the colorimetric method, along with long storage stability achieved by sol-gel immobilization, demonstrated the potentiality of this technique to be used for commercial purpose.
authors: IMAGES EA 4218, Batiment S, University of Perpignan, 52 Avenue Paul Alduy, Perpignan Cedex, France.
authors: Akhtar
authors: A
authors: Hayat
authors: Lise
authors: L
authors: Barthelmebs
authors: Jean-Louis
authors: JL
authors: Marty
mesh_terms: D056893:Alveolata / Q000737:chemistry*; D003124:Colorimetry; D004795:Enzyme Stability; D004800:Enzymes, Immobilized / Q000737:chemistry*; D019319:Okadaic Acid / Q000737:chemistry / Q000302:isolation & purification*; D044367:Phase Transition; D054648:Protein Phosphatase 2 / Q000737:chemistry*
chemical_list: D004800:Enzymes, Immobilized; D019319:Okadaic Acid; D054648:Protein Phosphatase 2