GC-ECD Detector

[jijualex]

Can anybody please clear doubt about the make up gas usage in GC- ECD detector. Can i use Helium as Carrier and Make up gas? i dont want to use Nitrogen as make up gas. Any other combination of Carrier and makeup gases?

[dblux_]

Can anybody please clear doubt about the make up gas usage in GC- ECD detector. Can i use Helium as Carrier and Make up gas? i dont want to use Nitrogen as make up gas. Any other combination of Carrier and makeup gases?

Yes you may use He as makeup gas. But why not nitrogen, it's much cheaper.

[sry]

ECD works based on ionization of a proper gas by beta emission of Ni-63 radiactive element. Helium could not be ionized by this radaition and so no ions are produced. Nitrogen or argon/methan mixture could be readily ionized in ECD detecctors and usually are used as make-up gas in capillary columns selection.

[thohry]

Carrier gas can be N2 or He, but makeup gas must be N2 (or mix of CH4 and Ar). ECD needs electrons and those gas can be ionized by radiation of 63 Ni can be use as ECD make up.

[Stunt]

I've been using argon/methane (P5) mixture for 20 + years. Go with that. The nitrogen is cheaper, but less effective.

[CE Instruments]

I've been using argon/methane (P5) mixture for 20 + years. Go with that. The nitrogen is cheaper, but less effective.

Whose detector ? From my experience with the Carlo Erba/Thermo detector Nitrogen was often better due to a higher background noise with Ar/ME