J. Phys. Chem. A, 2019, 123 (1), pp 313–322 DOI: 10.1021/acs.jpca.8b11417
Ionization of 2-nonanone, cyclopentanone, acetophenone, pyridine, and di-tert-butylpyridine (DTBP) in a corona discharge (CD) atmospheric pressure chemical ionization (APCI) ion source was studied using ion mobility (IMS) and time-of-flight mass spectrometry (TOF–MS). The IMS and MS spectra were recorded in the absence and presence of ammonia dopant. Without NH3dopant, the reactant ion (RI) was H+(H2O)n, n = 3,4, and the MH+(H2O)x clusters were produced as product ions. Modeling of hydration shows that the amount of hydration (x) depends on basicity of M, temperature and water concentration of drift tube. In the presence of ammonia (NH4+(H2O)nas RI) two kinds of product ions, MH+(H2O)x and MNH4+(H2O)x, were produced, depending on the basicity of M. With NH4+(H2O)n as RI, the product ions of pyridine and DTBP with higher basicity were MH+(H2O)x while cyclopentanone, 2-nonanone, and acetophenone with lower basicity produce MNH4+(H2O)x. To interpret the formation of product ions, the interaction energies of M–H+, H+–NH3, and H+–OH2 in the M–H+–NH3 and M–H+–OH2 and M–H+–M complexes were computed by B3LYP/6-311++G(d,p) method. It was found that for a molecule M with high basicity, the M–H+ interaction is strong leading in weakening of the H+–NH3, and H+–OH2 interactions in the M–H+–NH3 and M–H+–OH2 complexes.
MaSaTECH will participate on SMI2G meeting, 29-30th January 2019, Brussels
We are proud that Portable Advanced Ion Mobility Spectrometer was successfully tested and implemented to mobile robotic arm by group of Dr. Jankiewicz from Institute of Optoelectronics, Warsaw Military University of Technology. The PAIMS was successfully tested for remote detection of explosives from various surfaces. The high sensitivity of PAIMS was supported by our unique Laser Desorption technique developed for analysis of solids and surfaces.
Whisky lactone (WL) in oak staves / barrels has the biggest share in the resulting taste of beverages. The quantity of WL in oak wood have strong effect on quality of final products. Based on WL quantity, the barrel’s staves are divided into ten categories. This categories are category1 (0-7 μg/g), ......, category10 (63-70 μg/g). In this application report we are introducing the ion mobility spectrometer as useful tool for fast monitoring and quantification of whisky lactone in oak wood.
The ion mobility spectrometry technique offers advantages like high sensitivity (ppb range), fast response (ms range), compact design, operation in atmospheric pressure and ability to separate the isomeric compounds. As ion mobility spectrometers do not work in vacuum, the ion movement is not straightforward. There occur huge numbers of ion-molecule interactions between charged ions and neutral particles of a drift gas. Thus the ion separation in IMS is not based just on their mass but also on their cross section. This gives an advantage to the IMS technique for fast separation of isomers. In this Lab-Report we will demonstrate the ability of AIMS technique to separate the isomeric compounds.
INNMS 2016 Moscow - Invited lecture
Journal of Chromatography A, Volume 1459, 12 August 2016, p. 145–151. DOI: 10.1016/j.chroma.2016.06.069.
We present a novel method for coupling thin layer chromatography (TLC) with ion mobility spectrometry (IMS) using laser desorption technique (LD). After separation of the compounds by TLC, the TLC surface was sampled by the LD-IMS without any further manipulation or preparation. The position of the laser was fixed and the TLC plate was moved in desired directions by the motorized micro-positioning stage. The method was successfully applied to analyze the TLC plates containing explosives (tri nitro toluene, 1,3,5-trinitro- 1,3,5-triazacyclohexane, pentaerythritol tetranitrate, 2,4-dinitro toluene and 3,4-dinitro toluene), amino acids (alanine, proline and isoleucine), nicotine and diphenylamine mixtures and detection limits for these compounds were determined. Combination of TLC with LD-IMS technique offers additional separation dimension, allowing separation of overlapping TLC analytes. The time for TLC sampling by LD-IMS was less than 80 s. The scan rate for LD is adjustable so that fast and effective analysis of the mixtures is possible with the proposed method.
Anal. Chem., 2015, 87 (14), p. 7389–7394. DOI: 10.1021/acs.analchem.5b01585.
We present a new technique suitable for direct liquid sampling and analysis by ion mobility spectrometry (IMS). The technique is based on introduction of a droplet stream to the IMS reaction region. The technique was successfully used to detect explosives dissolved in methanol and oil as well as to analyze amino acids and dipeptides. One of the main advantages of this technique is its ability to analyze liquid samples without the requirement of any special solution.