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How do I interpret my mass spectrum EI?

Interpretation of Mass Spectra—EI-MS

  1. Must be the ion peak of the highest mass.
  2. Must be an ion peak with an odd charge.
  3. Reasonable fragments can be lost, and ion peaks with reasonable mass numbers appear, such as M-1, M-15, M-18, M-28, M-44, etc.
  4. The mass number must conform to the nitrogen rule.

What does ESI stand for in mass spectrometry?

Electrospray ionization (ESI) is a technique to generate ions for mass spectrometry using electrospray by applying a high voltage to a liquid to produce an aerosol.

How does TOF mass spec work?

A common form of mass spectrometry is time of flight (ToF) mass spectrometry. In this technique, particles of the substance are ionised to form 1+ ions which are accelerated so that they all have the same kinetic energy. The time taken to travel a fixed distance is then used to find the mass of each ion in the sample.

What is TOF in Maldi Tof?

In time of flight (TOF) mass spectrometry, ionized oligo molecules are accelerated by an electrostatic field in the mass analyzer to a common kinetic energy. With the same kinetic energy, lighter ions travel faster and heavier ions travel more slowly.

What is the base peak on mass spectrum?

Base peak: The most intense (tallest) peak in a mass spectrum, due to the ion with the greatest relative abundance (relative intensity; height of peak along the spectrum’s y-axis).

What is TOF in MALDI Tof?

What is ESI source?

Electrospray ionization (ESI) is a mainstay of LC/MS that can be used to analyze large and small analytes. The Agilent electrospray ion source uses patented orthogonal nebulization and a heated counterflow drying gas system to achieve excellent sensitivity and robust, reliable performance.

How are ions formed in a TOF?

Time of Flight (TOF) Mass Spectrometer Electrospray Ionisation: The sample is dissolved in a volatile solvent and injected through a fine hollow needle at high pressure. As the solvent evaporates it is subjected to a high voltage which forms positive ions (because it loses electrons).