A thermal desorption unit has been interfaced to an electrospray ionization-ion mobility-time-of-flight mass spectrometer. The interface was evaluated using a mixture of six model volatile organic compounds which showed detection limits of <1 ng sample loaded onto a thermal desorption tube packed with Tenax, equivalent to sampled concentrations of 4 microg L(-1). Thermal desorption profiles wer...

High-resolution ion mobility/time-of-flight techniques were used to measure collision cross sections for 968 tryptic digest peptide ions obtained from digestion of common proteins. Here, we report a mobility signature that aids in identifying proline-containing peptides containing 4-10 residues. Of 129 peptides (< or = 10 residues in length) in the database that contain proline residues, 57% sh...

Q040curve is definite evidence of the presence of an ion of age equal to 0.04 seconds and mobility 13.1 cm/sec. per volt/cm. While this latter value is not exact owing to the lack of resolving power of the method under such conditions, particularly with the low current intensity obtained in hydrogen ionized by x-rays, the agreement with the value obtained by Loeb is extremely good in view of th...

An extensive study of two current ion mobility resolving power theories ("conditional" and "semi-empirical") was undertaken using a recently developed drift tube ion mobility-mass spectrometer. The current study investigates the quantitative agreement between experiment and theory at reduced pressure (4 Torr) for a wide range of initial ion gate widths (100 to 500 μs), and ion mobility values (...

We report the first results from a new instrument capable of acquiring infrared spectra of mobility-selected ions. This demonstration involves using ion mobility to first separate the protonated peptide Gly-Pro-Gly-Gly (GPGG) into two conformational families with collisional cross-sections of 93.8 and 96.8 Å(2). After separation, each family is independently analyzed by acquiring the infrared p...

This paper aims to cover the main strategies based on ion mobility spectrometry (IMS) for analysis of biological samples. The determination endogenous and exogenous compounds in such samples is important understanding health status individuals. For this reason, development new approaches that can be complementary ones already established (mainly liquid chromatography coupled mass spectrometry) ...