Design and Performance Evaluation of a Linear Ion Trap Mass Analyzer Featuring Half Round Rod Electrodes

Abstract

Abstract. A novel linear ion trap mass analyzer featuring half round rod electrodes (HreLIT) has been built. It is mainly composed of two pairs of stainless steel electrodes which have a cross-section of half round rod and a pair of end electrodes. The HreLIT has a simple structure and so it could be assembled by hand with relatively high mechanical accuracy. The external dimension of HreLIT is 50 mm×29.5 mm× 28 mm (length×width×height) and its internal volume is about 3.8 cm 3 . A home-made HreLIT mass spectrometer with three-stage vacuum system was built and the performance of HreLIT was characterized using reserpine solution and PPG standard solution. When the scan rate was 254 u/s, mass peak with FWHM of 0.14 u was achieved for ions with m/z 609, which corresponds to a mass resolution of 4350. The HreLIT was also operated at a low q value of 0.28 to extend its mass range. The experiment result showed a mass range of over 2800 u and the amplitude of radio frequency (rf) signal was only 1560 V (0-p). Three-stage tandem mass spectrometry was successfully performed in the HreLIT, and the collision-induced dissociation (CID) efficiencies of MS 2 (CID of ions with m/z 609) and MS 3 (CID of ions with m/z 448) were 78% and 59%, respectively.

Miniature and Fieldable Mass Spectrometers: Recent Advances

“…123 The latest reports of conventional machining are arc-shaped electrodes 60 mm in length 129 and half round rod electrodes 46 mm in length with 5.0 mm rod radii. 128 …”

Linear ion trap mass selectivity with impulse power supply and sinusoidal dipolar excitation

“…The linear ion trap with round rods and with transverse resonance injection of Gly‐Phe‐Leu ions ( m/z 336) used in this experiment has been described in detail elsewhere . In this experiment, a rectangular waveform power supply was used to drive the ion trap mass analyzer.…”

“…[27] EXPERIMENTAL The linear ion trap with round rods and with transverse resonance injection of Gly-Phe-Leu ions (m/z 336) used in this experiment has been described in detail elsewhere. [34][35][36][37] In this experiment, a rectangular waveform power supply was used to drive the ion trap mass analyzer. The period of the rectangular trapping waveform can be precisely controlled and adjusted at a resolution of 50 ps for both ion trapping and resonance Figure 7.…”

Linear ion trap with added octopole field component: the property and method

“…The halo IT, a simplified toroidal IT, employs two parallel planar electrode substrates on which numerous electrode rings are imprinted . There are also several simplified versions of the LIT, such as the rectilinear ion trap (RIT), the mesh‐electrode linear ion trap (MeLIT), the ion trap array (ITA), the printed circuit board ion trap (PCBIT), the triangular‐electrode linear ion trap (TeLIT), the two‐plate LIT and the linear ion trap featuring half round rod electrodes (HreLIT) …”

“…[15,16] There are also several simplified versions of the LIT, such as the rectilinear ion trap (RIT), [17] the meshelectrode linear ion trap (MeLIT), [18] the ion trap array (ITA), [19] the printed circuit board ion trap (PCBIT), [20] the triangular-electrode linear ion trap (TeLIT), [21] the two-plate LIT [22] and the linear ion trap featuring half round rod electrodes (HreLIT). [23] In all of the above LITs except the linear quadrupole IT, ions are mass-selectively ejected in the radial direction during mass analysis, and consequently, ejection slots need to be manufactured on electrodes for ejection. Because of the presence of ejection slots and the fact that the electrodes are truncated, even for the LIT with standard hyperbolic geometry, the internal electric field is not a pure quadrupole field, and field distortions described by the addition of some higher order field components are inevitable.…”