Chromatography Forum

Dear chromatographers.

how many months Does a MS filament usually last?.
I think that my Dynatherm ACEM 900 thermal desorption or a Tekmar P&T are killing my Shimadzu´s filaments, I changed the last one only three months ago!!!
maybe There is a leak somewhere and the oxigen is consuming the hot filament.

thank you very much.

Life of a filament depends on instrument condition and samples being run.

If you have a leak in the sytem, you will shorten the filament life. But, you can have a tight system and have the filaments operating while the solvent peak or other large peaks are eluting from the column and still kill the filament.

I've had some methods an instruments where 3 monts was a good filament life and others where a year or so was typical.

Don is right about filament life being different from instrument to instrument. Especially on a P&T system with so much water getting into the system. We used to burn through filaments quicker than on the SVOC system we had. However, three months does seem a little quick. I would double check for leaks and check all your P&T parameters to make sure you are not letting excess water into the system.

On the other hand I know nothing about Shimadzu instruments so this may be typical for a Shimazu P&T system. I would call the vendor after exhausting all other in-house options.

pueblito,

Are you using the solvent delay to let the air peak or water peak go by? Can you get away with this in your analysis?

Best regards,

AICMM

Dear Don and Tlahren, thanks for your reply.
In fact there always are problems when I try to perform an autotuning when I load methods and use instruments like thermal desorption or P&T.
And I have another question: Do you have problems like air leak when using thermal desorption or P&T, is your autotuning result OK?.

Dear AICMM.
When I do SVOC in general the shortest time for solvent cut time is about 5 minutes ( standard 30m 0.25mm column) and for VOCs is about 4 minutes ( for a VOCOL 60m 0.53mm) injection port operated in "direct mode" in this case.

thanks.

It could also be a bad batch of filaments, check with the supplier. I experienced this with filaments for some years ago.
AB

Thanks Andersb, I will check it with de supplier.
Ironically It is supposed that there were improvements in the design of filaments.

thanks.