Volume : 12, Issue : 10, October – 2025

Title:

A MINI-REVIEW OF MAJOR IONIZATION TECHNIQUES IN MASS SPECTROMETRY: MECHANISMS AND APPLICATIONS

Authors :

B.Akhila and B.Lakshman Kumar

Abstract :

Mass spectrometry (MS) has become a routine and vital analytical technique in the life sciences, with ion formation (ionization) serving as the critical first step. Various ionization methods have been developed, each suited to specific classes of analytes. Among them, Electrospray Ionization (ESI) and Matrix-Assisted Laser Desorption Ionization (MALDI) are the most widely used soft ionization methods. ESI generates ions from charged droplets through either the ion evaporation or charge residual model, making it ideal for polar and large biomolecules. MALDI, in contrast, utilizes laser energy and a matrix to facilitate ionization, effectively analyzing biomolecules such as peptides and proteins. For less polar or nonpolar compounds, Atmospheric Pressure Chemical Ionization (APCI) and Atmospheric Pressure Photoionization (APPI) are often more effective. A major advancement occurred in 2004 with the introduction of ambient mass spectrometry, which allows ionization directly from samples in their natural environment with minimal preparation. The most prominent techniques in this category are Desorption Electrospray Ionization (DESI) and Direct Analysis in Real Time (DART). This mini-review provides an educational overview of the major ionization techniques and their mechanisms, aimed at students and researchers new to the field of MS.
Key Words: Mass spectrometry (MS), Ionization, Electrospray ionization (ESI), Matrix-assisted laser desorption ionization (MALDI), Atmospheric pressure chemical ionization (APCI), Atmospheric pressure photoionization (APPI), Chemical ionization.

Cite This Article:

Please cite this article in press B.Lakshman Kumar et al A Mini-Review Of Major Ionization Techniques In Mass Spectrometry: Mechanisms And Applications, Indo Am. J. P. Sci, 2025; 12(10).

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