I'm currently using the LUMOS II FTIR microscope to analyze the chemical composition of microplastic particles. But recently, I keep getting the same spectrum (see image), whether on different particles of my sample or on the nylon plate. Do you have any idea of the underlying problem?
It is hard to read. But does look like some form of background.
How are you measuring? Could this be related to some form of sample carrier (glass plate or anything like it?) Are you measuring in ambient air or aqueous enviroment? The peaks could be some water (vapor or liquid) peaks or similar molecules, which are present in the ambient air.
Can you flush your FTIR during measurements with some inert, dry gas? N2 or something?
I agree with Michael Rüsing, blow the measurement chamber with N2 if you have the opportunity. Such a double signal at about 2400 cm^(-1) usually comes from absorption of IR light by carbon dioxide.
Greetings,
Piotr Wieczorek
Looks like a purge problem - Have you tried collecting a 100% line?
I always used CO2 and H2O purged air (also used on my main spectrometer bench too). I've never used nylon plates, but I wonder if they are totally absorbing the IR light? Have you tried more traditional plate e.g. KBr or diamond?
- Badges
- Science topic