Mass spectrometry (MS) is an analytical technique used to measure the mass-to-charge ratio (m/z) of ions. It helps identify the composition, structure, and quantity of molecules in a sample. Essentially, it tells us what molecules are present and in what amounts.
Here’s a simple breakdown of how it works:
- Ionization: The sample is converted into charged particles (ions) using techniques like Electron Ionization (EI) or Electrospray Ionization (ESI).
- Acceleration: These ions are accelerated in an electric field to give them kinetic energy.
- Deflection/Separation: The ions are passed through a magnetic or electric field that separates them based on their mass-to-charge ratio (lighter ions or higher charged ions are deflected more).
- Detection: The separated ions are detected, and a mass spectrum is produced, showing peaks corresponding to different m/z values.
Applications of Mass Spectrometry:
- Determining molecular weight of compounds
- Identifying chemical structures
- Detecting impurities or trace elements
- Studying proteins, metabolites, and pharmaceuticals
In short, mass spectrometry is like a molecular scale and fingerprint detector for molecules.