Peru’s most advanced mass spectrometer at PUCP


Dr. Alfredo Ibáñez, director of the Instituto de Ciencias Ómicas y Biotecnología Aplicada at PUCP (ICOBA for its acronym in Spanish), commented on the acquisition of the most advanced mass spectrometer in Peru: Q-Exactive Orbitrap HF, from ThermoFisher Scientific installed in the Microanalysis area, of the first floor of Building O, in our University.

In general terms, what is a mass spectrometer?

A mass spectrometer is an analytical instrument that ionizes chemical species. The ions, produced within the mass spectrometer, are separated and detected on the basis of their electrical mass-charge relationship. In simpler terms, it is a balance-like instrument that can measure, in a very accurate way, the weight of an ionized molecule. What differentiates this acquisition from previous ones is that the Q-Exactive Orbitrap is the first high-resolution mass spectrometer installed in Peru.

What are its functions?

Mass spectrometry has several uses, which can be described in terms of qualitative as well as quantitative analyses. Some of the functions of a mass spectrometer include, but are not limited to: identification of unknown compounds based on their elemental composition (molecular weight), determining the origin of a sample on the basis of the compounds composing it, determining the structure of a compound by observing its fragmentation (and / or complementing the structural information from nuclear magnetic resonance equipment) and quantifying the amount of a particular compound in a sample, etc.

What are its technical specifications?

  • Resolution 240,000 for a molecule with a m / z of 200
  • Mass range of 50 to 6000 m/z.
  • Mass accuracy (with an internal standard): <1 ppm RMS.
  • Mass accuracy (with an external standard): <3 ppm RMS.
  • Full MS sensitivity: 500 fg (0.000 000 000 000 5 grams) of buspirone.
  • Dynamic range > 5000: 1

The instrument is composed of an ionization source, a mass analyzer, and a detector.

The ionization sources that PUCP has are: source of electrospray ionization (ESI), source of secondary electrospray ionization source (SESI), source of atmospheric pressure photoionization (APPI), source of atmospheric pressure chemical ionization (APCI), source of direct analysis in real-time (DART), and source of matrix-assisted laser desorption/ionization (MALDI). The analyzer and mass detector consist of the Q-Exactive Orbitrap.

In this case the mass spectrometer of PUCP can be connected to a liquid chromatography system or to a gas chromatography system.

What needs does it satisfy for researchers?

The Q-Exactive Orbitrap HF allows to identify and quantify more proteins, peptides, lipids, glycans and small molecules with greater precision and in less time than with a traditional mass spectrometer. The Q-Exactive HF combines a quadrupole for the selection of precursor ions with the mass analyzer called “high resolution Orbitrap.” This combination can offer the user a superior speed of analysis and a greater power in the resolution of the signals obtained by the instrument. In addition, it offers better accuracy in mass (units after the decimal point). All this is reflected in a better spectral quality and sensitivity; allowing better identification and quantification within a single analysis.

What kind of research works can be conducted?

Depending on the field of interest, this instrument can conduct (but is not limited to) the following types of research:

Applications in different industries: food safety, quality control in industrial processes as in production of materials (polymers), clinical analysis, monitoring of environmental pollution, etc. Research in different fields, such as proteomics: identification of proteins and post-transnational modifications, quantification of specific proteins, study of interaction between proteins and other molecules, etc.; and the field of metabolomics: metabolic identification, variations between different cohorts of people (patients / controls), etc.