Mass Spectrometry Concepts and Applications

These flashcards cover key vocabulary terms and concepts related to mass spectrometry, its techniques, and applications.

Mass Spectrometry

An analytical tool used to determine the mass of a molecule by measuring the mass-to-charge ratio (m/z) of molecules in a sample.

MALDI-ToF-MS

Matrix Assisted Laser Desorption/Ionization Time-of-Flight Mass Spectrometry, a type of mass spectrometry that uses laser energy to ionize samples.

Electrospray Ionization (ESI)

A soft ionization technique used mainly for peptides and proteins to create ions by applying a voltage to a liquid sample.

Post-Translational Modifications

Chemical modifications that occur to a protein after its translation, impacting its function.

Charge Envelope

The range of ion charges observed from a single parent molecule, important for analyzing mass-to-charge ratios in mass spectrometry.

Isotope

Atoms of the same element that have the same number of protons but different numbers of neutrons, resulting in different masses.

Resolution

The ability of a mass spectrometer to distinguish between ions of different m/z values; higher resolution indicates better separation.

Average Molecular Weight (MW)

The weighted average of the molecular weights of an element's isotopes as they occur naturally.

De novo peptide sequencing

Determining the amino acid sequence of a peptide directly from mass spectrometry data without prior knowledge of the sequence.

Charge-to-Mass Ratio (m/z)

A measure used in mass spectrometry where 'm' is the mass of an ion and 'z' is the charge; important for identifying different ions.

Matrix-Assisted Laser Desorption Ionization (MALDI)

A technique that uses laser energy for the ionization of analytes, typically employed for large biological molecules.

Time-of-Flight (TOF)

An analyzer in mass spectrometry that measures the time it takes for ions to travel a set distance, used to determine their m/z.

Fragile Ionization

The tendency of certain ionization methods to cause fragmentation in larger molecules during the ionization process.