Mass Spectrometry Report

MM 3320 : Report

Mass Spectrometry

Submitted by Velu K R NA12B033

Introduction

Mass Spectroscopy is an instrumental method for identifying the chemical constitution of a substance by means of the separation of gaseous ions according to their differing mass and charge. This method helps identify the amount and type of chemicals present

The Detector: The separated ions are then measured, and the results displayed on a chart.

Mass spectrometry has both qualitative and quantitative uses. These include determining the structure of a compound, quantifying the amount of a compound in a sample and determining the isotopic composition of elements in a molecule. This technique basically studies the effect of ionizing energy on molecules. It depends upon chemical reactions in the gas phase in which sample molecules are consumed during the formation of ionic and neutral species.

The ion source or the ionizer converts a portion of the sample into ions. There is a wide variety of ionization techniques depending on the state (solid, liquid, gas).

An extraction system removes ions from the sample, which are then targeted through the mass analyzer and onto the detector. The mass analyzer sorts the ions by their mass to charge ratio.

The detector measures the value of an indicator quantity and thus provides data for calculating the abundances of each ion.

Some detectors are capable of diving spatial information, for example a multichannel plate detector gives spatial information

Principle

Mass spectroscopy is performed using a mass spectrometer.

Mass

Ionization refers to the production of gas phase ions suitable for resolution in the mass analyser or mass filter. There are a many on sources available, each has advantages and disadvantages for particular applications. For example, Electron Ionization (EI) gives a high degree of fragmentation, yielding highly detailed mass spectra which when skilfully analyzed can provide important information about structural elucidation/characterization and facilitate identification of unknown compounds by comparison to mass spectral libraries. However, EI is not suitable for coupling to High-performance liquid chromatography, since at atmospheric pressure, the filaments used to generate electrons burn out rapidly. Thus EI is coupled predominantly with Gas Chromatography, where the entire system is under high