Internal standard for organochlorinated pesticides

[thohry]

Hi all,

We are analyzing organochlorinated pesticides by GC-ECD with HP5-MS column . Now I want to use some internal standards to improve the quality. What compounds would you recommend to be the istd ?

Thanks

[tlahren]

Are you using single or dual column? Which pesticides? I'm fairly certain you will find some answers on page 10 of this U.S. EPA method 8081. http://www.accustandard.com/asi/pdfs/ep ... /8081B.pdf

Hope this helps,
Ty

[thohry]

Thank you very much. I use single column.

[tlahren]

I always say 'The more, the merrier' with internal standards. I would use both of them if you can resolve them from other analytes and the two recommended surrogates are almost a necessity for GC/ECD. Many times in my past they have helped solve chromatographic issues as well as ensuring the integrity of the results.