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Chemistry Forums for Students => Analytical Chemistry Forum => Topic started by: SYG on October 23, 2007, 11:37:34 AM

Title: GC-MSMS Problem
Post by: SYG on October 23, 2007, 11:37:34 AM
Hello,

I am studying on pesticide analysis with GC-MSMS system. After the first injection of the standards to the system, the peaks are getting worse and worse and the sensitivity decreases. I changed the liner (we use Agilent  5181-3316 Liner 4 mm ID tap), O-ring, gold plated seal, cut 50 cm. off the column, changed the Helium cylinder but the problem remains unsolved. The Mass Spectroscope is working good because it shows good peaks when we inject Heptacosa from the Mass part. I think the problem lies within the GC part. Can you propose a solution? I can't find a way out..Thank you in advance...
Title: Re: GC-MSMS Problem
Post by: enahs on October 23, 2007, 09:19:28 PM
How old is your GC-MS?

I ask because you might find you will get better support by calling or emailing the manufacture. They usually have people to help with questions like this. Sometimes it does require you paid extra for a support contract....

The thing about it here is you are going to find people will be very timid about offering advice, cause well, we do not want to damage a expensive piece of equipment because of lack of information or miss-communication! Which is very easy to do in a situation like this.



Title: Re: GC-MSMS Problem
Post by: SYG on October 24, 2007, 03:45:37 AM
It is 1 year old, the technical support team is also trying to figure out the source of the problem, but I haven't got any solutions yet.
Title: Re: GC-MSMS Problem
Post by: vtnhuy on April 28, 2008, 09:59:57 PM
How about checking the contamination in detector or column ? You can read how to bake out the detector in the trouble shooting in GC book .