This article describes a liquid chromatography/mass spectrometry method that has been successfully applied to the sensitive and simultaneous determination of the pesticides Simazine, Thiobencarb, and Thiuram. The method is selective and sensitive, making it suitable for the determination of these pesticides in drinking water.
This document describes a liquid chromatography/mass spectrometry (LC/MS) method using electrospray ionization in positive ion mode for the simultaneous determination of the pesticides Simazine, Thiobencarb, and Thiuram. The method addresses the need for better selectivity and sensitivity compared to existing techniques, particularly for Thiuram.
| Instrument | Agilent 1100 Liquid Chromatograph/Mass Spectrometer |
|---|---|
| Ionization Mode | Electrospray ionization positive ion mode |
| Drying Gas Flow | 8 L/min |
| Nebulizer Pressure | 40 psi |
| Fragmentor Voltage (Thiuram) | 40 V |
| Mass Range | 100-500 amu |
| Mobile Phase A | CH3OH/30 mM CH3COONH4 (50/50) |
| Mobile Phase B | CH3CH3 |
| Gradient | 0 % to 100 % B in 20 min |
| Flow Rate | 0.2 mL/min |
| Oven Temperature | 40 °C |
| Injection Volume | 50 uL |
| Column | Inertsil ODS3, 3.1 mm id x 250 mm long x 5 um |
| Detection Limit (Simazine) | 0.02 ppb |
| Detection Limit (Thiuram) | 2.5 ppb |
| Detection Limit (Thiobencarb) | 1 ppb |
The method is suitable for the simultaneous determination of Simazine, Thiuram, and Thiobencarb.
The detection limits are 0.02 ppb for Simazine, 2.5 ppb for Thiuram, and 1 ppb for Thiobencarb.
The analysis uses an Agilent 1100 Liquid Chromatograph/Mass Spectrometer with electrospray ionization.