This application note describes a method for the direct aqueous injection and automated on-line solid phase extraction (SPE) analysis of phenoxy herbicides in drinking water using the Varian 320-MS triple quadrupole LC/MS/MS. The method provides high sensitivity, selectivity, and analysis speed, meeting the requirements for trace-level quantitation of phenoxy herbicides in drinking water.
This document describes an analytical method for the trace-level quantitation of 17 phenoxy herbicides in drinking water. The method utilizes a fully automated, on-line Solid Phase Extraction (SPE) system coupled with the Varian (now Agilent) 320-MS Triple Quadrupole LC/MS/MS system. This approach allows for the analysis of the complete sample rather than an aliquot, improving detection capabilities while saving time and labor. The system prevents contamination and evaporation losses due to its closed nature.
The method achieves a limit of detection (LOD) of less than 20 ng/L for all studied compounds. Reproducibility over 10 injections at a routine surveillance level of 100 ng/L is less than 11% RSD. The analysis uses a 26-minute run time with linear calibration curves ranging from 20 to 500 ng/L.
| Limit of Detection (LOD) | less than 20 ng/L |
|---|---|
| Calibration Range | 20 to 500 ng/L |
| Reproducibility (RSD) | less than 11% |
| Run Time | 26 minutes |
| Injection Volume | 10 mL |
| Analytical Column | Polaris C18, 3 um, 100 x 2.0 mm |
The limit of detection is less than 20 ng/L for all compounds studied.
Ten replicate injections were performed at the routine surveillance level of 100 ng/L.