Why do we use mass spectrometry technique to detect the unknown compounds?

 

Mass spectrometry is a dominant analytical technique used to specify known materials, to analyze unknown compounds within a sample, and to clarify the structure and chemical properties of different molecules.

Mass spectrometry is an analytical tool useful for calculating the mass-to-charge ratio (m/z) of one or more molecules present in a sample.  These analysis can often be used to measure the exact molecular weight of the sample components as well.

Typically, mass spectrometers can be used to analyze unknown compounds via molecular weight conviction, to evaluate known compounds, and to resolve the structure and chemical properties of molecules.

Mass spectrometry can be used to figure out the molecular structure of organic compounds such as 2-butanone. In this approach, the compound of concern is ionized in a void chamber, and the charges and masses of the ions that separate from the compound are detected.

The main principle of mass spectrometry (MS) is to obtain ions from either inorganic or organic compounds by any relevant method, to separate these ions by their mass-to-charge ratio (m/z) and to detect them qualitatively and quantitatively by their respective m/z and prosperity.

How does a mass spectrometer achieve such a feat?  Each and every  mass spectrometer consists of these three components:

Ionization Source

Mass Analyzer

Ion Detection System

1. The Ionization Source

Molecules are transformed to gas-phase ions so that they can be moved about and manipulated by foreign electric and magnetic fields. In the laboratory we use a technique called nanoelectrospray ionization, which is somewhat similar to how cars are industrially designed. This method allows for generate positively or negatively charged ions, depending on the experimental requirements.  Nanoelectrospray ionization can precisely couple the outlet of a small-scale chromatography column directly to the basin of a mass spectrometer.  The flow from the column is crossed through a needle that is 10-15 um at its tip.

2. The Mass Analyzer

Once ionized, the ions are separated and sorted according to mass-to-charge (m/z) ratios. There are a number of mass analyst currently available, each of which has trade-offs relating to speed of activity, resolution of separation, and other operational requirements.  The specific types in use at the Broad Institute are deliberate in the next section.  The mass analyst often works in concert with the ion detection system.

3. Ion Detection System

The separated ions are then measured and sent to a data system where the m/z ratios are gathered together along with their relative affluence.  A mass spectrum is simply the m/z ratios of the ions present in a sample conspire against their intensities.  Each peak in a mass spectrum shows a component of different m/z in the sample, and heights of the peaks connote the relative affluence of the various components in the sample.