massspektrometrian

Mass spectrometry is an analytical technique used to measure the mass-to-charge ratio of ions. It is widely employed in chemistry, physics, biology, and medicine for identifying and quantifying unknown compounds, determining the isotopic composition of elements, and elucidating the structure of molecules. The process typically involves three main stages: ionization of the sample, separation of the ions based on their mass-to-charge ratio, and detection of the separated ions.

Various ionization methods exist, depending on the nature of the sample and the desired information. Electron ionization (EI) and chemical ionization (CI) are common for volatile organic compounds, while electrospray ionization (ESI) and matrix-assisted laser desorption/ionization (MALDI) are preferred for larger biomolecules like proteins and peptides. Once ionized, the ions are accelerated into a mass analyzer, where they are separated. Common mass analyzers include the quadrupole, time-of-flight (TOF), and magnetic sector. The detector then records the abundance of ions at each mass-to-charge ratio, generating a mass spectrum.

The resulting mass spectrum is a plot of ion abundance versus mass-to-charge ratio. This spectrum provides a unique fingerprint for a given compound, allowing for its identification by comparison to spectral databases. Mass spectrometry is a powerful tool for determining molecular weight, identifying fragments of a molecule (which aids in structural elucidation), and quantifying the amount of a substance present in a sample. Its sensitivity and specificity make it indispensable in fields ranging from environmental monitoring and drug discovery to forensic science and proteomics.