Chromatography Forum

525.2 or 505 or....?
I'm calibrating alpha, gamma, and trans Nonachlor to 0.1 ppb on my gc/ms via the 525.2 reg mix from Accustandard... when i tried a 100 ppb chlordane std i got barely any ion abundances... they were there but not in the abundances i would need to quantify.
i would like to do a simple 505 liq.-liq. extraction for the chlordane but when i do the extraction and run it on my gc/ms my recoveries are horrible...
istd's and smc's are great, alpha,gamma, and trans are in the weeds....maybe i'm not spiking enough into the sample.
help....i may give myself a concussion soon...or severly damage the cinderblock wall in the lab...

Been there done that won't work. I do 525, and run my extracts scan for most all compounds and run them again on a sim method for toxaphene and chlordane.
What you need do is setup a sim version of your method. I use 5 peaks with the following quant ions for chlordane:
339
373 ( 2 peaks about 0.1 min apart)
375
409
The EPA set the limits on Tech chlordane so you MUST calibrate with tech grade.

I was just searching toxaphene by gc-ms and came across your post. I run svoc's using SBSE (twister) and would like to run toxaphene as well. I run all my compounds using SIM, but tried one time before and was unable to get any increase in abundance. Can you send me the ions you use and let me know what kind of RL you are able to see down to? I need to see 0.1ppb.

https://nepis.epa.gov/Exe/ZyNET.exe/P10 ... e=x&ZyPURL

Really long url but it will take you to EPA Method 525.3 which has instructions on how to do technical gradeToxaphene and Chlordane by gc/ms. It should help you get down to the level you need. If you need more sensitivity then you can look into EPA Method 508 using gc/ecd.

We analyze the 525.2 extract by 508.1 to get the sensitivity for some pesticides, toxaphene and chlordane. Just have to make sure the DCM is exchanged.

We also see very erratic aldrin recoveries by this procedure as you note in another post. We also had erratic aldrin recoveries when we used EPA 508 with mtbe final solvent. I never remember this problem with hexane exchanges in 608,8080,8081 methods.