Mass spectrometer device

Mass spectrometer: device measuring mass-to-charge ratio of ions, essential in analytical chemistry and biochemistry.

About this subject

A mass spectrometer is an analytical instrument that determines the composition of a sample by ionizing its components and separating the ions based on mass-to-charge ratio. The process involves three key steps: ionization (e.g., by electron impact or electrospray), acceleration and deflection by electric and magnetic fields, and detection. The result is a mass spectrum showing the relative abundance of each ion.

The technique originated in early 20th century with pioneering work by J.J. Thomson and Francis Aston, who built the first mass spectrograph and identified stable isotopes. Today, mass spectrometers are essential in chemistry, molecular biology, and medicine, used to identify proteins, metabolites, drugs, contaminants, and even carbon-14 dating.

Various types exist: quadrupole, time-of-flight (TOF), magnetic sector, and Fourier-transform ion cyclotron resonance (FT-ICR). Each offers advantages in resolution, sensitivity, and mass range. Mass spectrometry is often coupled with liquid or gas chromatography for complex mixture analysis.

In everyday life, it is used in doping tests, clinical diagnostics (newborn screening), food and beverage quality control, and pharmaceutical purity testing. Advances are leading to portable spectrometers for field analyses.

Frequently Asked Questions

How does a mass spectrometer work?

It ionizes sample molecules, separates ions by mass-to-charge ratio using electric and magnetic fields, and detects each ion, producing a mass spectrum.

What is mass spectrometry used for in medicine?

It is used in diagnostics, such as newborn screening for metabolic disorders, protein identification in cancer, and monitoring of therapeutic drugs.

What is the difference between a quadrupole and a TOF mass spectrometer?

A quadrupole uses four rods to filter ions, while TOF measures the time ions take to travel a tube, determining mass. TOF offers higher resolution and mass range.