The BioPharma Finder application supports the following fragmentation methods for mass spectral (MS) data:

Table Fragmentation methods supported in BioPharma Finder

Acronym

Name

Description

CID

collision-induced dissociation

Molecular ions are accelerated to high kinetic energy in the vacuum of a mass spectrometer and then allowed to collide with neutral gas molecules such as helium, nitrogen, or argon. The collision breaks the bonds and fragments the molecular ions into smaller pieces.

ETciD

electron transfer collision-induced dissociation

Hybrid ETD and CID fragmentation method, which involves an initial electron-transfer dissociation step and produces additional b and y ions.

IR-ETciD

infrared-activated electron transfer collision-induced dissociation

Infrared-induced activation and desolvation coupled with the standard ETciD method.

HCD

higher-energy collision-induced dissociation

Ion optics accelerate the precursor ions into a high-pressure cell, where they collide with nitrogen gas. The projectile ion has laboratory-frame translation energy higher than 1 keV.

EThcD

electron transfer higher-energy collision dissociation

Hybrid ETD and HCD fragmentation method, which involves an initial electron-transfer dissociation step and produces additional b and y ions.

IR-EThcD

infrared-activated electron transfer higher-energy collision dissociation

Infrared-induced activation and desolvation coupled with the standard EThcD method.

ETD

electron transfer dissociation

Singly charged reagent anions transfer electrons to protonated peptides within an ion trap mass analyzer to induce fragmentation. ETD cleaves randomly along the peptide backbone, while side chains and modifications (such as phosphorylation), are left intact. This method is used to fragment peptides and proteins.

IR-ETD

infrared-activated electron transfer dissociation

Infrared-induced activation and desolvation coupled with the standard ETD method.

SID

surface-induced dissociation

Molecular ions collide with a target surface composed of a relatively rigid material to maximize fragmentation.

ECD

electron capture dissociation

Protonated molecules are introduced to low-energy free electrons. Capture of the electrons releases electric potential energy and reduces the charge state of the ions by producing odd-electron ions, which easily fragment.

IRMPD

infrared multi-photon dissociation

An infrared laser is directed at the ions in an ion trap mass analyzer. The precursor ions absorb multiple infrared photons until they reach more energetic states and begin to break bonds, resulting in b and y fragment ions.

UVPD

ultraviolet photodissociation

Ultraviolet photons activate the proteins for fragmentation, providing ultra-high resolution for improved structural elucidation and quantitation of isobaric compounds.

PTCR

proton transfer charge reduction

Multiply-charged ions transfer protons to a neutral, basic carrier gas, gently reducing the charge states and simplifying mass spectra without fragmenting the molecule, which is especially useful for top-down analysis of proteins.