title: Validation of pyrithiobac sodium (Staple herbicide) ELISA for Australian cotton soils.
abstract: An enzyme-linked immunosorbent assay (ELISA) for pyrithiobac-sodium (Staple) produced by DuPont was validated in Australian soils. This pyrithiobac-sodium ELISA was shown to be highly sensitive with the limit of detection of 4-5 ppt. Soil samples were extracted either in PBS buffer by shaking or by accelerated solvent extraction (ASE). While pyrithiobac sodium can be analyzed directly by ELISA after ASE extraction with 1/10 or more dilutions, the analysis of PBS extract required filtration and dilution 1/20 or more depending on the concentration. Immunoassay results compared favorably with GC-MS results for both ASE and PBS extract of incurred residue of pyrithiobac sodium in soil samples, indicating that this ELISA can be an inexpensive and reliable alternative to conventional residue analysis methods for quantification of pyrithiobac-sodium. This validation provided the basis for applying the ELISA to a field study of pyrithiobac-sodium.
authors.affiliation: School of Land, Water and Crop Sciences, The University of Sydney, Sydney, NSW, Australia. s.wang@agec.usyd.edu.au
authors.forename: Shuo
authors.initials: S
authors.lastname: Wang
authors.forename: Helen L
authors.initials: HL
authors.lastname: Beasley
authors.forename: Sheldon R
authors.initials: SR
authors.lastname: Sumpter
authors.forename: Ivan R
authors.initials: IR
authors.lastname: Kennedy
mesh_terms: D001565:Benzoates / Q000032:analysis*; D004797:Enzyme-Linked Immunosorbent Assay / Q000379:methods*; D008401:Gas Chromatography-Mass Spectrometry; D006540:Herbicides / Q000032:analysis*; D010573:Pesticide Residues / Q000032:analysis*; D012680:Sensitivity and Specificity; D012989:Soil Pollutants / Q000032:analysis*
chemical_list: D001565:Benzoates; D006540:Herbicides; D010573:Pesticide Residues; D012989:Soil Pollutants; C401888:pyrithiobac sodium