Low-Cost, Compact Quadrupole Mass Filters with Unity Mass Resolution via Ceramic Resin Vat Photopolymerization.

This study reports novel, compact, and additively manufactured quadrupole mass filters (QMFs) with adequate filtering performance for practical mass spectrometry applications. The QMFs are monolithically fabricated via vat photopolymerization of glass-ceramic resin using 57 µm × 57 µm × 100 µm voxels, and selective electroless plating of nickel-boron. Experimental characterization of QMF prototypes at 1.

Accurate Sizing of Nanoparticles Using a High-Throughput Charge Detection Mass Spectrometer without Energy Selection.

The sizes and shapes of nanoparticles play a critical role in their chemical and material properties. Common sizing methods based on light scattering or mobility lack individual particle specificity, and microscopy-based methods often require cumbersome sample preparation and image analysis. A promising alternative method for the rapid and accurate characterization of nanoparticle size is charge detection mass spectrometry (CDMS), an emerging technique that measures the masses of individual ions.

Systematic Ligand Effects in the Reactions of Fe(D) and FeX(Δ) with CFX (X = Cl, Br, I). Ion Mobility Measurements of FeX(Δ) (X = F, Cl, Br, I) in He.

The gas phase reactions of Fe(D) and FeX(Δ) with CFX (X = Cl, Br, I) were examined using a selected-ion drift cell reactor under near-thermal energetic conditions. All reactions were carried out in a uniform electric field at a total pressure of 3.5 Torr at room temperature.

Surface-Induced Dissociation of Protein Complexes in a Hybrid Fourier Transform Ion Cyclotron Resonance Mass Spectrometer.

Mass spectrometry continues to develop as a valuable tool in the analysis of proteins and protein complexes. In protein complex mass spectrometry studies, surface-induced dissociation (SID) has been successfully applied in quadrupole time-of-flight (Q-TOF) instruments. SID provides structural information on noncovalent protein complexes that is complementary to other techniques.

Coupling an electrospray source and a solids probe/chemical ionization source to a selected ion flow tube apparatus.

A new ion source region has been constructed and attached to a variable temperature selected ion flow tube. The source features the capabilities of electron impact, chemical ionization, a solids probe, and electrospray ionization. The performance of the instrument is demonstrated through a series of reactions from ions created in each of the new source regions.

Performance evaluation of a Loeb-Eiber mass filter at 1 Torr.

The Loeb-Eiber mass filter is best operated at relatively high pressures-such as 1 Torr-where collisional dampening of ions up to the mass filter thermalizes the ions' kinetic energy, which is a requirement for effective filtering. The inter-electrode gaps of ~8 μm require rf amplitudes on the order of 0-5 V p-p at approximately 50 MHz to achieve mass filtering up to m/z 40. Mass filtering between the 25-μm diameter wires, therefore, takes place on time frames less than the collision frequency at ~1 Torr.