Quantitative protein measurements by mass spectrometry have gained wide acceptance in research settings. However, clinical uptake of mass spectrometric protein assays has not followed suit. In part, this is due to the long-standing acceptance by regulatory agencies of immunological assays such as ELISA assays. In most cases, ELISAs provide highly accurate, sensitive, relatively inexpensive, and...

Desorption electrospray ionization may be used as a fast and convenient method for analysis and identification of lipids in the cell culture. Oxidative stress, which usually involves changes in lipids, was used as a model of pathology to show the utility of this analysis methodology. This paper addresses the surface preparation of cell culture slides, induction of oxidative stress, and cell mon...

A B ST R A C T : We studied electron impact ionization of tetramethylsilane (TMS), Si(CH3)4, which is utilized in plasma polymerization applications, using a semi empirical Jain-Khare theoretical technique. Absolute partial cross sections for the formation of all fragment ions were measured by Jain-Khare method from threshold up to 120 eV. We obtained the following sixteen ions: CH3, Si, SiH, S...

Several topics are covered, namely, general aspects important for mass determination of peptides and proteins, sample preparation for both ESI and MALDI, and various mass analyzers coupled to these ionization techniques. Finally, the discussion is carried out on peptide and protein mass analysis as related to accuracy and precision of mass determination for both ESI-MS and MALDI-MS.

Mass spectrometric imaging allows the investigation of the spatial distribution of molecules at complex surfaces. The combination of molecular speciation with local analysis renders a chemical microscope that can be used for the direct biomolecular characterization of histological tissue surfaces. MS based imaging advantageously allows label-free detection and mapping of a wide-range of biologi...

[1] Electron capture and ionization cross sections for protons and nitrogen ions incident on N2 are measured in the energy range 10–100 keV using time of flight (TOF) coincidence counting techniques. In the case of proton impact the formation of N2 + ions dominates for both electron capture and ionization channels at all energies, whereas for N ions, the N2 + formation dominates for electron ca...