Abraxis: 520001: Diuron by Immunoassay, Microtiter Plate
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Official Method Name
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Abraxis Diuron Plate Assay Kit (96T) PN 520001 |
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Current Revision
| 2003 |
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Media
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WATER |
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Instrumentation
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Immunoassay |
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Method Subcategory
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Organic |
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Method Source
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Citation
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Brief Method Summary
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Diuron is detected using a colorimetric immunoassay (ELISA) procedure. A sample (0.05 mL) and an enzyme conjugate (enzyme-labeled Diuron) are added to a microtiter plate well pre-coated with Diuron-specific antibodies. Both the Diuron in the sample and the enzyme conjugate compete for antibody binding sites on the wells in proportion to their concentrations. At the end of an incubation period, the wells are washed and a substrate is then added which is catalyzed by the enzyme and converted from a colorless to a blue solution. The reaction is terminated with the addition of a dilute acid. The concentration of Diuron in the sample is determined by measuring its absorbance at a specific wavelength (450 nm) using a plate photometer and comparing its absorbance to the absorbance of the calibrators. |
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Scope and Application
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This method determines Diuron in water (groundwater, surface water, well water). |
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Applicable Concentration Range
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0.03 - 3.0 |
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Interferences
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Cross-reactivity: Neburon, Chlorbromuron, Linuron, and high concentrations of Chlortoluron and Propanil produce false positive responses for Diuron. |
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Quality Control Requirements
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(A) Calibration with 5 standards and 1 blank, all analyzed in duplicate. (B) Precision: All 40 samples are analyzed in duplicate. (C) Accuracy: 3 matrix samples spiked with the target analyte at 3 different levels in the range for quantitative analysis. (D) Validation: Analysis of 4 positive and 4 negative samples by an independent method for confirmation. |
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Sample Handling
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Samples are collected in glass containers with Teflon-lined caps; for compliance monitoring, samples should be held no longer than 14 days. If samples are held frozen, they can be held for longer periods of time. Immunoassay reagents are stored refrigerated until use. Samples containing gross particulate matter should be filtered using a 1 micron filter or centrifuged before use. Drinking water samples are typically dechlorinated with 0.008% sodium thiosulfate. |
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Maximum Holding Time
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14 days at 4oC, longer if held frozen |
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Relative Cost
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Less than $50 |
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Sample Preparation Methods
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