 
            
        This is an Application Brief and does not contain a detailed Experimental section.
This application brief highlights about analysis of endothall in drinking water and soil.
The compound analyzed in this study is endothall.
 
            
        | Column: | Symmetry Shield RP8, 2.1 x 100 mm, 3.5 μm | 
| Part number: | WAT058969 | 
| Mobile phase: | 5% Acetonitrile in 1% formic acid/water | 
| Flow rate: | 200 μL/min | 
| Injection volume: | 75 μL | 
| Detection: | Electrospray (negative ion), (SIR mode, m/z = 185) | 
| Instrument: | Waters Alliance LC-MS with Micromass Platform LC Mass Detector | 
| Column: | RTX 5 capillary, 30 meters, 0.25 mm ID, 0.25 μm film thickness | 
| Carrier gas: | Helium @ 30 cm/sec | 
| Temp program: | 40 °C initial, 8 °C/ min to 300 °C | 
| Injection volume: | 1 μL | 
| Detection: | HP 5972 MSD, (EI, SIM mode, m/z = 123) | 
A) For LC-MS: No derivatization required. The MTBE* in the eluent is removed by evaporation and the extract is adjusted to a final volume of 1.0 mL with 10% methanol in water.
B) For GC: The eluent is heated for 40 min @ 60° C to convert endothall to the dimethyl ester. The ester is then extracted with DCM**. After removal of water by treatment with Na2SO4, the DCM** extract is evaporated to a final volume of 0.5 mL.
Soil Samples: The sample (10 g) is extracted with 35 mL pH 10 carbonate buffer (0.1M) followed by 20 mL of water. The combined extracts are adjusted to pH 2 with phosphoric acid and centrifuged. SPE is then performed using the same protocol as water samples.
* methyl butyl ether 
** methylene chloride 
 
            
         
            
         
            
        WA31764.77, June 2003