massaspectrometrie: complexe analyse

The analysis of complex mixtures requires the combination of separation methods and mass spectrometry in sequence, termed hyphenated methods.

GC–MS is the most common hyphenated method, where a thermally stable volatile mixture is separated by gas chromatography, and the column output is continually sent to the mass spectrometer for ionization and analysis.

Similarly, LC–MS is liquid chromatography coupled with a mass spectrometer.

Typically, a mixture with nonvolatile polar or ionic compounds is separated by liquid chromatography, and the output is ionized by electrospray ionization before being sent to the mass analyzer.

However, mixtures with less-polar molecules often use other atmospheric-pressure ionization methods.

Tandem mass spectrometry is another hybrid method for analysis, where two mass analyzers are connected in series.

Unlike GC–MS and LC–MS, tandem mass spectrometry offers separation in milliseconds, and it is more sensitive and selective.

Interestingly, highly complex mixtures can be analyzed by coupling GC or LC with tandem mass spectrometry, forming GC–MS/MS and LC–MS/MS.