Chromatography Forum: GC Archives: Thiram(TMTD)
Top of pagePrevious messageNext messageBottom of pageLink to this message  By Ahn, Jongsung on Sunday, January 9, 2000 - 02:35 am:

I'm trying to develop multiresidue method for pesticide residue on soybeen sprout, as soybeen sprout is major source of public health concern in korea
Target compouds are captan, carboxine, thiram, cabendazim and thiabendazole but we employ single residue method respectively with different detector. especially thiram is derivatized with benzil chlorid and detected by ECD therefore the analysis is time and labor consuming
According to literature, thiram(dithiocarbamates) is rather unstable and many degration products can be formed. routine methods are based on the spectrophotometric determination of carbon disulfide released on hot acid digestion of sample. A sensitive determination of CS2 is also possible by means of headspace GC. Another sensitive and specific method is use of HPLC

Benzile chlorated thiram can be stabilized and easily detected by ECD. therefore I think original thiram may be determined with new technique.

Although I lowered injection port temperature(80). chormatogram was surged like hyperbolic curve as oven temperature arised

With powerful ion trap, It's easy to separate and detect captan, carboxin and thiabendazole simutaneously so far

Can anyone give me some information about thiram detection with ion trap


Top of pagePrevious messageNext messageBottom of pageLink to this message  By Scott Fredrickson on Tuesday, January 11, 2000 - 01:48 pm:

We've done the CS2 evolution analysis, and I have a trap, but no info on derivatized Thiram on the trap.

80 is very low--probably too low--for an injection temp for derivatized Thiram. The other pesticides mentioned certainly won't work at that temp for a typical splitless injection. Are you using the SPI injector?

I'm guessing you are missing the peak because it is eluting quickly, or is at too low a concentration for the detector.

I'd try the same conditions that work for the ECD, to begin with. If it works on the ECD, it should work on the trap, only at a different (higher) concentration. Could the compound be eluting before the detector is turned on? Be careful not to burn out the filaments! Try a slower oven ramp.

If you have a working, sensitive, specific LC method for Thiram, use it. GC will probably be nothing but trouble. If not now, later.

Top of pagePrevious messageNext messageBottom of pageLink to this message  By Anonymous on Wednesday, March 15, 2000 - 05:24 am:

The Art Of Chemistry

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