Sciencemadness Discussion Board

Advice on which analytical instrument to buy: FTIR, NMR, GCMS, GS, MS, NIR, etc

beerwiz - 30-8-2016 at 19:08

It's very frustrating to do experiments and not know the final outcome of the reactions. I'm now thinking about buying an analytical instrument to identify the compounds that have been formed after the reaction. Looking for an instrument that's $20,000 or less.

It must be able to separate the compounds in a mixture, analyze them, and then automatically match it with potential compounds in a database. The instrument must come with a database(s) of most compounds.

Which instrument do you recommend?

[Edited on 31-8-2016 by beerwiz]

Dr.Bob - 30-8-2016 at 19:26

Depends on what you are doing, but hard to buy an NMR for $20,000, the liquid helium alone costs that much every year. The best choices are a used GC-MS or a LC-MS, if you can find one and maintain it. There are a lot of used ones out there, some might be close to that price, but not trivial to set up, operate or use.

For pure compounds, IR, FTIR, or NIR can be helpful, and libraries are available, but not much help on mixtures. Cheaper still is MP, BP, optical refraction, density, and other simple tests.

Better bet is to find someone, a company, university, or small company with this equipment and work there, even if part time. A friend works for an analytical company part time and has access to some incredible instrumentation.

beerwiz - 30-8-2016 at 19:34

I guess I can run a TLC plate to separate the compounds and run it on IR, FTIR, or NIR to identify each compound. With TLC the sample size is very small unless a prep-TLC is done, in which case 10-100mg can be collected.

IR looks the most promising since it is the cheapest. Any recommendations for a good IR unit with database(s) for automatching compounds?

[Edited on 31-8-2016 by beerwiz]