Ultraviolet Photodissociation Induced by Light‐Emitting Diodes in a Planar Ion Trap

Abstract

The first application of light-emitting diodes (LEDs) for ultraviolet photodissociation (UVPD) mass spectrometry is reported. LEDs provide ac ompact, low cost light source and have been incorporated directly into the trapping cell of an Orbitrap mass spectrometer.M S/MS efficiencies of over 50 % were obtained using an extended irradiation period, and UVPD was optimizedb ym odulating the ion trapping parameters to maximizet he overlap between the ion cloud and the irradiation volume.Supportinginformation and the ORCID identification number(s) for the author(s) of this article can be found under: http://dx.

Ultraviolet Photodissociation Mass Spectrometry for Analysis of Biological Molecules

“…For example, LEDs (emission wavelengths of 255, 265, and 275 nm) were inserted directly into a trapping cell to allow UVPD and mass analysis using an Orbitrap mass spectrometer, as illustrated in Figure 51. 58 Although the fragmentation efficiency was modest owing to the low photon flux of the LEDs, the strategy demonstrated the ability to use inexpensive light sources for photodissociation in a manner that required no external optics. 58 Even more recently, a low-cost helium-discharge lamp was interfaced to a commercial Q-TOF mass spectrometer, offering another means to activate ions and promote photodissociation using very high energy photons.…”

“…58 Although the fragmentation efficiency was modest owing to the low photon flux of the LEDs, the strategy demonstrated the ability to use inexpensive light sources for photodissociation in a manner that required no external optics. 58 Even more recently, a low-cost helium-discharge lamp was interfaced to a commercial Q-TOF mass spectrometer, offering another means to activate ions and promote photodissociation using very high energy photons. 22 In this case, UV irradiation of multicharged ions resulted in electron detachment and radical-directed fragmentation.…”

“…53−55 A variety of light sources have been used for UVPD, including excimer lasers (e.g., F 2 : 157 nm, 7.9 eV per photon; 42 ArF: 193 nm, 6.4 eV per photon; 47 and XeF: 351 nm, 3.5 eV per photon 56 ), solid state Nd:YAG lasers (213 nm, 5.8 eV per photon; 52 266 nm, 4.7 eV per photon; 44 or 355 nm, 3.5 eV per photon 43 ), gas-discharge lamps, 22 synchrotron radiation, 57 and even light-emitting diodes (LEDs) in one report. 58 More powerful lasers or ones with high repetition rates enable UVPD on a fast time scale and are particularly beneficial for higherthroughput LC-MS applications. Tunable lasers have also been employed, affording the ability to evaluate UVPD over a broader range of wavelengths to enable ion spectroscopy experiments.…”

Instrumentation at the Leading Edge of Proteomics

“…Beyond Q-Orbitraps and Q-TOFs, the versatility, sensitivity, speed, and stand-alone capabilities of ion traps drove their adoption into diverse instrument architectures, most notably in combination with high-resolution Orbitrap and FTICR mass analyzers. In the first-generation Orbitrap systems, like the LTQ Orbitrap XL, LTQ Orbitrap Velos, and Orbitrap Elite hybrid systems, the LIT functions as both the m/z isolation device and the reaction cell for ion activation, although a dedicated collision cell was introduced behind the C-trap in later models , and multipurpose dissociation cell options were explored. , In 2013, the LIT-Orbitrap coupling was reimagined as a Tribrid MS system that integrates the Q-Orbitrap-LIT architecture to enable faster scan speeds (∼20 Hz) and more versatility through parallelization of various mass analyzer functions . In these instruments, an rf-only storage cell called the ion routing multiple (IRM) exists between the C-trap and the LIT, and the IRM functions as the central routing hub for ions during scan functions in addition to being the bCID collision cell.…”

Lipid Analysis by Mass Spectrometry coupled with Laser Light

“…Light sources : For UVPD, several alternative light sources including 255, 265, and 275 nm light emitting diodes (LEDs), [152] extreme‐UV (40–80 nm) gas‐discharge lamps [153] and vacuum‐UV (115–160 nm) deuterium lamps [154] have been investigated. Such lower‐cost and user‐friendly light sources can replace lasers in some applications and are expected to boost the widespread use of UVPD [6c] …”