Current Role and Potential of Triple Quadrupole Mass Spectrometry in Biomedical Research and Clinical Applications.

Mass-spectrometry-based assays nowadays play an essential role in biomedical research and clinical applications. There are different types of commercial mass spectrometers on the market today, and triple quadrupole (QqQ) is one of the time-honored systems. Here, we overview the main areas of QqQ applications in biomedicine and assess the current level, evolution, and trends in the use of QqQ in these areas.

Negative Atmospheric Pressure Chemical Ionization of Chlorinated Hydrocarbons Studied by Ion Mobility Spectrometry (IMS) and IMS-MS Techniques.

Negative polarity atmospheric pressure chemical ionization of selected chlorinated hydrocarbons (tetrachloromethane CCl and hexachloroethane CCl, dichloromethane CHCl, trichloromethane CHCl, 1,1,1,2-tetrachloroethane 1,1,1,2-CHCl, 1,1,2,2-tetrachloroethane 1,1,2,2,-CHCl 1,1,2-trichloroethane 1,1,2-CHCl, and 1,1,2-trichloroethane 1,1,2-CHCl) was studied using ion mobility spectrometry (IMS) and IMS combined with time-of-flight mass spectrometer (IMS-TOF MS) techniques, in the dry air and at two different drift gas temperatures (323 and 373 K). The ionization was performed using the OCO(HO) reactant ions (RIs), and the dominant ionization reaction was the dissociative electron transfer. The ionization resulted in the appearance of Cl ions for all substances and [OH.

Investigation by simulation of the RF carpets for the transport of ions at atmospheric pressures.

Ion funnels, quadrupole, and multipole are well-known ion optic methods for transportation of ions. However, the methods are suitable for pressures below 30-40 Torr. The main loss of ions occurs in an inlet of mass spectrometer at atmospheric pressure.

Influence of multiplexing conditions on artefact signal and the signal-to-noise ratio in the decoded data in Hadamard transform ion mobility spectrometry.

In Hadamard transform ion mobility spectrometry (HT IMS), the signal-to-noise ratio is always lower for non-modified pseudorandom sequences than for modified sequences. Since the use of non-modified modulating pseudorandom sequences is strategically preferable from a duty cycle standpoint, we investigated the change in the interference signal when transitioning from non-modified modulating sequences to sequences modified by the addition of 1,3,5 and 7 zeros. The interfering signal in HT IMS with modified pseudorandom sequences was shown to be mainly random noise for all the cases except for modifying by incorporation of 1 zero.

Novel approach to constructing laser ionization elemental time-of-flight mass spectrometer.

The main advantages of laser sampling are associated with following features: sample preparations as well as consumables are not needed, low risk of sample contamination, good spatial resolution. In mass spectrometry, high laser irradiance can be used for both ablation and ionization processes. The method is especially profitable in time-of-flight mass spectrometry.

Loading of mass spectrometry ion trap with Th ions by laser ablation for nuclear frequency standard application.

We describe an original multisectional quadrupole ion trap aimed to realize nuclear frequency standard based on the unique isomer transition in thorium nucleus. It is shown that the system effectively operates on Th, Th and Th ions produced by laser ablation of metallic thorium-232 target. Laser intensity used for ablation is about 6 GW/cm.

Mass selective laser cooling of Th in a multisectional linear Paul trap loaded with a mixture of thorium isotopes.

We consider an experiment on trapping and laser cooling of Th ions in a linear Paul trap in the presence of undesirable impurities such as ions of the radioactive isotope Th. We suggest a method of separating these impurities by means of selective laser cooling utilizing the isotope shift of cooling transitions in Th and Th ions. According to our estimation, the isotope shift is equal to 3.

Rapid identification of triphenylmethane dyes by ion mobility time-of-flight mass spectrometry.

An ion mobility time-of-flight mass spectrometry (IM-TOFMS)-based method has been preliminarily investigated for the identification of triphenylmethane ballpoint pen dyes on paper. The dyes were sampled from one-year-old ballpoint pen ink entries. The entries were written on paper documents stored in the dark in a bookcase.

Determination of traces of uranium and thorium in titanium and copper used for the construction of the Russian Emission Detector 100 by inductively coupled plasma mass spectrometry.

The Russian Emission Detector 100 (RED-100) under construction at the National Research Nuclear University MEPhI (Moscow Engineering Physics Institute) is designed to detect the presently undiscovered effect of coherent neutrino scattering. One of the factors limiting the sensitivity of the detector is the spontaneous decay of uranium and thorium in the detector materials. Radioactive impurities in detector materials at levels of parts per billion can significantly affect the sensitivity.

Multisectional linear ion trap and novel loading method for optical spectroscopy of electron and nuclear transitions.

There is a growing need for the development of atomic and nuclear frequency standards because of the important contribution of methods for precision time and frequency measurements to the development of fundamental science, technology, and the economy. It is also conditioned by their potential use in optical clocks and quantum logic applications. It is especially important to develop a universal method that could allow one to use ions of most elements effectively (including ones that are not easily evaporated) proposed for the above-mentioned applications.

Separation of isomeric amines with ion mobility spectrometry.

Eight selected isomeric amines were ionized using atmospheric pressure chemical ionization and atmospheric pressure photoionization producing a protonated molecule [M+H](+) for each amine. The mobility of these ions was measured by ion mobility spectrometry. The amine compound class was shown to have an important role in mobility separation of the amines.

Analysis of new synthetic drugs by ion mobility time-of-flight mass spectrometry.

Characteristic ion mobility mass spectrometry data, reduced mobility, and limits of detection (signal-to-noise ratio = 3) were determined for six synthetic drugs and cocaine by ion mobility time-of-flight mass spectrometry (IM-TOF-MS) with electrospray ionization (ESI) and atmospheric pressure chemical ionization (APCI). The studied synthetic illicit drugs recently appeared on the recreational drug market as designer drugs and were methylone, 4-MEC (4'-methylethcathinone), 3,4-MDPV (3,4-methylenedioxypyrovalerone), JWH-210 [4-ethylnaphthalen-1-yl-(1-pentylindol-3-yl)methanone], JWH-250 [2-(2-methoxyphenyl)-1-(1-pentyl-1H-indol-3-yl)ethanone], and JWH-203 [1-pentyl-3-(2'-chlorophenylacetyl) indole]. Absolute reduced mobilities in nitrogen were 1.

Development of an atmospheric pressure ion mobility spectrometer-mass spectrometer with an orthogonal acceleration electrostatic sector TOF mass analyzer.

Recently developed ion mobility mass spectrometer is described. The instrument is based on a drift tube ion mobility spectrometer and an orthogonal acceleration electrostatic sector time-of-flight mass analyzer. Data collection is performed using a specially developed fast ADC-based recorder that allows real-time data integration in an interval between 3 and 100 s.

Letter: A simple ion source set-up for desorption/ionization on silicon with ion mobility spectrometry and ion mobility spectrometry-mass spectrometry.

Using a simple ion source set-up, laser desorption/ionization on silicon (DIOS) was demonstrated with the use of a custom-made drift tube ion mobility spectrometer (IMS), mounted on a commercial triple quadrupole mass spectrometer, and with an IMS equipped with a Faraday plate detector. DIOS was tested by mobility measurement of tetrapropylammonium iodide, tetrabutylammonium iodide and tetrapentylammonium iodide, whilst 2,6-di-tert- butylpyridine was used as a standard. The reduced mobilities measured for the test halides are in concordance with previously obtained ion mobility spectrometry-mass spectrometry data.

Separation of different ion structures in atmospheric pressure photoionization-ion mobility spectrometry-mass spectrometry (APPI-IMS-MS).

This study demonstrates how positive ion atmospheric pressure photoionization-ion mobility spectrometry-mass spectrometry (APPI-IMS-MS) can be used to produce different ionic forms of an analyte and how these can be separated. When hexane:toluene (9:1) is used as a solvent, 2,6-di-tert-butylpyridine (2,6-DtBPyr) and 2,6-di-tert-4-methylpyridine (2,6-DtB-4-MPyr) efficiently produce radical cations [M](+*) and protonated [M + H](+) molecules, whereas, when the sample solvent is hexane, protonated molecules are mainly formed. Interestingly, radical cations drift slower in the drift tube than the protonated molecules.

Sterically hindered phenols in negative ion mobility spectrometry-mass spectrometry.

Negative corona discharge atmospheric pressure chemical ionization (APCI) was used to investigate phenols with varying numbers of tert-butyl groups using ion mobility spectrometry-mass spectrometry (IMS-MS). The main characteristic ion observed for all the phenolic compounds was the deprotonated molecule [M-H](-). 2-tert-Butylphenol showed one main mobility peak in the mass-selected mobility spectrum of the [M-H](-) ion measured under nitrogen atmosphere.

Interfacing an aspiration ion mobility spectrometer to a triple quadrupole mass spectrometer.

This article presents the combination of an aspiration-type ion mobility spectrometer with a mass spectrometer. The interface between the aspiration ion mobility spectrometer and the mass spectrometer was designed to allow for quick mounting of the aspiration ion mobility spectrometer onto a Sciex API-300 triple quadrupole mass spectrometer. The developed instrumentation is used for gathering fundamental information on aspiration ion mobility spectrometry.

Tetraalkylammonium halides as chemical standards for positive electrospray ionization with ion mobility spectrometry/mass spectrometry.

Chemical standards for positive ion mode electrospray ionization ion mobility spectrometry/mass spectrometry (ESI(+)-IMS/MS) are suggested. The low clustering tendency of tetraalkylammonium halides makes them ideal chemical standards for ESI(+)-IMS/MS. A homologous series of these compounds forms a useful external standard for instrument testing and resolution calibration of an IMS instrument.

Development of an ion mobility spectrometer for use in an atmospheric pressure ionization ion mobility spectrometer/mass spectrometer instrument for fast screening analysis.

An ion mobility spectrometer that can easily be installed as an intermediate component between a commercial triple-quadrupole mass spectrometer and its original atmospheric pressure ionization (API) sources was developed. The curtain gas from the mass spectrometer is also used as the ion mobility spectrometer drift gas. The design of the ion mobility spectrometer allows reasonably fast installation (about 1 h), and thus the ion mobility spectrometer can be considered as an accessory of the mass spectrometer.