Mass spectrometry detection

If we consider only a few of the general requirements for the ideal polymer/additive analysis techniques (e.g. no matrix interferences, quantitative), then it is obvious that the choice is much restricted. Elements of the ideal method might include LD and MS, with reference to CRMs. Laser desorption and REMPI-MS are moving closest to direct selective sampling tandem mass spectrometry is supreme in identification. Direct-probe MS may yield accurate masses and concentrations of the components contained in the polymeric material. Selective sample preparation, efficient separation, selective detection, mass spectrometry and chemometric deconvolution techniques are complementary rather than competitive techniques. For elemental analysis, LA-ICP-ToFMS scores high. 

Tarantilis, P. A., G. Tsoupras et al. (1995). Determination of saffron (Crocus sativa L.) components in crude plant extracts using hihg-performance liquid chromatography-UV-visible photodiode array detection-mass spectrometry. J. Chromat. A 699 107-118. 

DAGAN, S., Comparison of gas chromatography-pulsed flame photometric detection-mass spectrometry, automated mass spectral deconvolution and identification system and gas chromatography-tandem mass spectrometry as tools for trace level detection and identification, J. Chromatogr., A., 2000,868,229-247. 

Schultz JC, Hack CA, Benner WH (1998) Mass determination of megadalton-DNA electrospray ions using charge detection mass spectrometry. J Am Soc Mass Spectrom 9 305-313... 

Methods in the analysis of drug impurities (e.g., ultraviolet, UV Fourier transform infrared, FT-IR nuclear magnetic resonance, NMR mass spectrometry, MS) are used to separate, identify, and quantify impurities, as well as establish their structure. Currently the most efficient methods seem to be combined techniques such as GC-MS, LC-MS, liquid chromatography-diode-array detection-mass spectrometry (LC-DAD-MS), LC-NMR, LC-DAD-NMR-MS, etc. [18-20]. 

The use of NCW as the mobile phase in liquid chromatography was recently reviewed. In this area, in addition to its green credentials, NCW is compatible with a range of detection methods flame ionization detection, mass spectrometry (MS) and UV (to short wavelengths). The reason for the recent growth in this area is the development of more thermally stable stationary phases. It has been used to analyse a growing number of analytes (alkylbenzenes, phenols, ketones, carboxylic acids, amino acids, carbohydrates and some pharmaceuticals). For example, carbohydrates (monosaccharides, disaccharides and sugar... 

The final determination of the CBs was performed by capillary gas chromatography with electron capture detection mass spectrometry was used as complementary technique to confirm the identity of each of the CBs determined. Each participant had validated its method by performing experiments on recovery, extraction efficiency, procedure blanks and detector linearity. The seven individual CB calibrants were supplied to the participants as pure, crystalline CRMs from BCR (CRMs Nos. 291,293, 294,295, 296. 297 and 298). Each laboratory was requested to prepare separate calibration solutions of the appropriate concentration, in iso-octane, to calibrate the detector and lying within its linear range. The use of at least one internal standard was mandatory the participants, however, were left free to select the internal standard(s) best suited to their methods. They had to verify that the selected compounds did not occur in the candidate reference material or did not interfere with compounds present in the material. A series of pure dichlorobenzylalkyl ethers (DCBEs) was made available to the participants but other internal standards were also accepted of which the list is given in the certification report [21] along with additional details on calibration procedures. 

Mueller, W., Schubert, J., Benzing, A., and Geiger, K., Method for analysis of exhaled air by microwave energy desorption coupled with gas chromatography-flame ionization detection-mass spectrometry, J. Chromatogr. B, 716, 27-38, 1998. 

Lopez de Alda, M. and Barcelo, D., Determination of steroid sex hormones and related synthetic compounds considered as endocrine disrupters in water hy liquid chromatography-diode array detection-mass spectrometry, J. Chromatogr. A, 892, 391-406, 2000. 

Odanaka, Y., Tsuchiya, N., Matano, O. and Goto. S. (1983). Determination of inorganic arsenic and methylarsenic compounds by gas chromatography and multiple ion detection mass spectrometry after hydride generation-heptane cold trap. Anal. Chem. 55, 929-932. 

Electron-molecule reactions This process is also referred to as electron capture detection mass spectrometry (ECD-MS), and is amenable to compounds containing electrophilic moieties (such as compounds with positive electron affinities). ECD-MS has been investigated and used extensively for analyses of many classes of environmental contaminants and for forensic toxicological applications. 

Dissolve 4 g a-cyclodextrin in 5 mL water. Adjust the pH value to 12 by NaOH solution. And mix with 1.4 g p-TsCl. Vigorously stir the mixture at room temperature for 5 min. The pH value would decline to 6.5. Filter the reaction solution, and separate the products by reversed-phase column. Three kinds of purified products would be detected. Mass spectrometry and NMR data showed that the three kinds of products were C-3, C-2 and C-6 position substituted toluene sulfonyl of-CDs [ 14]. 

Korenman, I. M. Method of organic compounds determination. Photometric analysis. M. (1970). De Villiers, A., Vanhoenacker, G., Majek, R, and Sondra, P. Determination of anthocyanins in wine by direct injection liquid Chromatography-diode array detection-mass spectrometry and classification of wines using discriminant analysis. J. Chromat.A., 1054 194-204 (2004). 

Simirgiotis, M.J., Caligari, P.D.S., and Schmeda-Hirschmann, G. 2009. Identification of phenolic compounds from the fruits of the mountain papaya Vasconcellea pubescens A. DC. grown in Chile by liquid chromatography-UV detection-mass spectrometry. Food C/tein. 115 775-784. 

Cai M, Jin M, Weavers LK (2011) Analysis of sonolytic degradation products of azo dye Orange G using liquid chromatography-diode array detection-mass spectrometry. Ultrason Sonochem 18 1068-1076... 

The elucidation of microscopic mechanisms of the elementary reactions was facilitated by the development of kinetic spectroscopy, particularly by the use of laser excitation and detection, mass spectrometry, and the state-selected molecular beams. 

Gas Detection Principles. Some of the more common gas detection principles used in toxie gas monitoring include electroehemistry, electro-optical detection, solid state detection, mass spectrometry, moleeular (or flame) emission speetrometry,irrfrared speetrophotometry, ionization teeh-niques, and thermal conduetivity. Brief deseriptions of several different gas detection technologies are deseribed below. 

The major benefits of H NMR spectroscopy are easy quantification and determination of steric arrangements. Disadvantages are the low sensitivity of the NMR detection and the fact that inorganic counterions and parts of the molecule without attached protons cannot be detected. Mass spectrometry, in contrast, is a very sensitive and selective detection technique steric information, however, cannot readily be obtained. Therefore, these two detection methods are mutually complementary for unambiguous structure elucidation purposes, a combined evaluation of both sets of data is highly desirable. 

Solid-Phase Extraction-Gas Chromatography-Atomic Emission Detection-Mass Spectrometry... 

ML Bao, K Barbieri, D Burrini, O Griffini, F Pantani. Determination of trace levels of taste and odor compounds in water by microextraction and gas chromatography-ion trap detection-mass spectrometry. Water Res 31 1719-1727, 1997. 

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