EPA Method 552.3 uses a liquid-liquid micro-extraction and runs the extracts through a GC-ECD in order to quantify haloacetic acids in drinking water. I have been the primary analyst on this method for about 6 months. While I have an operating procedure that works well, I am always looking to optimize and fine-tune certain aspects.
In every chromatography forum I have ever seen, a constant problem with Method 552.3 is the co-elution of monochloroacetic acid with other contamination peaks. I was thinking about attaching a liquid nitrogen dewar to the oven in order to change the start temperature of the temperature program from 30 degrees Celsius to 0 degrees Celsius. Does anyone have any experience with this? Is this worth my time and effort?
Also, I use two different Restek columns. Stx-CLPesticides 30 meter x 0.32 mmID x 0.32 um df, and Stx-CLPesticides2 30 meter x 0.32 mmID x 0.25 um df. My predecessor favored these columns, but said Agilent columns were very similar. Does anyone have any experience with the Agilent columns, and how much success do you have using them?
Any insight would be great! Even if it does not pertain to these two questions, any good tips anyone can think of would be helpful.