Selection of technique

[anandaraohs]

Hi

In a reaction monitoring system Starting material A is UV active and Starting material B is non UV active and the end product is UV active and decomposing on GC

In a matrix like this how to go ahead with the analysis which one to be selected which technique can be used
(Apart from universal detectors like ELSD or RID)

Thanks and regards

Anand

[chromatographer1]

I think the answer depends upon why you are monitoring? and if either analyte is in excess or not.

While this is not a GC question per se, I could see using TLC to monitor both beginning materials and the final product as well.

best wishes,

Rod

[Don_Hilton]

Depending on what you are doing, there are other options. Process monitoring offers different opportunities and constraints from monitoring a reaction in the lab that is to be run only a few times.

Ideas would include NMR, near infrared spectrometry, IR, LC. Does the nature of the chromophore change so that multiple wavelenghts can be used to measure the mixture and mathematically determine starting and final product concentrations (Chemometric solution)?

With GC, the product may decompose in the GC inlet - but perhaps it can be derivitized, a PTV type inlet can be used or on column injection can be used to avoid thermal degredation?

And the question is do you wish to monitor the depletion of one or more starting materials? The concentration of the desired product? The conentration of side products? All or some of the above?

More details might lead to a more specific answer. There are many options.