I am new to LC/MS analysis. I work for a small private agricultural laboratory doing pesticide residue analysis. We recently purchased a single quad instrument from Agilent. I am having trouble with carbamate pesticide analysis (EPA 8318 list) when looking for 1-naphthol (metabolite of carbaryl). I get very weak response using both electrospray and APCI. I have tried both ammoniumn acetate and ammonium formate buffers - varying strength and pH. I can get good response for all the other analytes and I know not everyone looks for 1-naphthol when doing carbamate analysis since it is just a metabolite. However, my boss would like it to be a part of our carbamate screen. Anyone else run into a problem with response for 1-naphthol or similar compound and have any solution? Thanks for the help.

Yes, I have analyzed for that compound. I also had poor sensitivity, in ESI and APCI. I was using a triple-quad, so that made up for it a little. I found that the negative modes (for ESI or APCI) were better than positive, although APCI positive also works.

1-Naphthol is heat snesitive, so it is usually lost in the clean-up of the extraction, prior to going on the LCMS. Make sure your sample doesn't get too hot. Barely bring it to dryness, then air the rest of the residue down. This might help improve your sensitivity.