Simple and crude, understand differences and correlations of GC, GCMS and ICP-MS in seconds---Nanjing Binglab

Puzzle from a newbie:

MS can be used for quantitative and qualitative analysis. Why do we need GC? What are the differences, connections, advantages and disadvantages of GC, GCMS, and ICP-MS?

Although many experimenters are using it, they may not be able to speak clearly.

How to simply and rudely clear up this confusion?

Breakdown one by one version

The gas phase separates mixtures using different partition coefficients. Qualitative and quantitative peak height (peak area) by retention time of different substances (peak height and peak area need to be obtained by various detectors, mass spectrometry is a kind of detector). Disadvantages: Qualitative is not accurate enough.

A mass spectrometer is a mass detector. Molecular masses of atoms or ions can be identified. Cooperating with various ion sources can break atoms into fragments. Qualitative by analyzing characteristic fragments and quantitative by response values. The disadvantage is that only the pure substance can be qualitative, and the mixture cannot be qualitative or quantitative.

ICP is a kind of atomic emission spectrum, please refer to a certain degree for the specific principle. ICP is an elemental analysis device. There is no comparison with GC.

Any combined technique is a means to use the advantages of the two devices and complement each other’s shortcomings in order to obtain more accurate results.

Mischievous version

MSD (MS) can be regarded as a kind of detector, such as FID, ECD, etc., but it is larger, and it is called GCMS with enough respect when naming it. GCMS is equivalent to adding an MSD detector to the GC.

Detailed version

MS can be quantitatively and qualitatively analyzed, but MS must be separated by GC and then detected by MS, and combined with GCMS. The prices of GC and GCMS are generally quite different. There are places where GC alone can solve the problem.

Experienced person version

It should be difficult to use the spectrum obtained from the mixture into MS, right?

After GC separation, the MS is relatively pure, and the mass spectrum of this pure substance is obtained, which can be used for qualitative and quantitative purposes.

GCMS generally measures compounds, and ICPMS measures elements.