Mass Spectroscopy

Abstract

Mass spectroscopy is an analytical technique used to measure m/z ratio of the charged particles (ions). Mass spectrometry can be used to determine the exact mass of the molecules ranging from large molecules like proteins to small molecules in the natural substances. In this chapter, the basic principle and steps involved in mass spectroscopy have been covered. The principle and working of ionization methods like matrix assisted laser desorption ionization (MALDI), electrospray ionization, atmospheric pressure chemical ionization, atmospheric pressure photoionization and mass analyzers like magnetic sector, time of flight (TOF) mass analyzer, triple quadrupole mass analyzer, and ion trap mass analyzer have been explained in detail. Various parameters used in acquisition like ion spray voltage, declustering potential (DP), curtain gas, CAD (collisionally activated dissociation) gas, collision energy (CE), collision cell exit potential, dwell time (DT), and cycle time have been discussed. The concept of tandem MS has also been touched upon. Advantages of mass spectrophotometer over other detectors have also been emphasized.