Material chromatographic/mass spectrometric

Analysis and Fate of Surfactants in the Aquatic Environment Sample Preparation for Trace Element Analysis Non-destructive Microanalysis of Cultural Heritage Materials Chromatographic-mass spectrometric food analysis for trace determination of pesticide residues... 

Besides the well-established chromatographic/mass spectrometric or spectroscopic methods there is always a need for complementary methods for the study of organic materials from art objects. The application of laser desorption/ionisation mass spectrometry (LDI-MS) methods to such materials has been reported only sporadically [12, 45 48] however, it is apparently increasing in importance. After GALDI-MS had been applied to triterpenoid resins, as described in Section 5.2, this relatively simple method was evaluated for a wider range of binders and other organic substances used for the production or conservation of artwork. Reference substances as well as original samples from works of art were analysed. 

Hara K, Nagata T, Kishimoto E, et al. 1980. Gas chromatographic/mass spectrometric demonstration of chlorinated aliphatic hydrocarbons in biological materials. Nippon Hoigaku Zasshi 34 507-512. 

Boenke, A., Certification of the mass concentration of three stilbenes in bovine urine reference materials by gas chromatographic-mass spectrometric methods. Sources of error and their control, Anal. Chim. Acta, 275, 3-8 (1993). 

All the factors discussed in this section influence the sensitivity of a gas chromatographic-mass spectrometric analysis. Ion yield in the mass spectrometer, number of ion species and their relative abundance, and slit settings for a desired resolution are also very important. In our experience the four major factors determining the amount that has to be injected to give full mass spectral information are retention time, losses on the column, column bleed, and distribution of ion species. Usually this amount is O.I-2.0 fig. However, less material (e.g., lOng) may be sufficient to show the major ions. It is clear that gas chromatography-mass spectrometry gives more structural information with ultramicro amounts than any other method. 

Reimendal, R., and Sjovall, J. B. Computer Evaluation of Gas Chromatographic-Mass Spectrometric Analyses of Steroids from Biological Materials... 

Almela, L., Sanohez-Munoz, B., Femdndez-Lopez, J.A., Roca, M.J., and Rabe, V. 2006. Liquid chromatographic-mass spectrometric analysis of phenolics and free radical scavenging activity of rosemary extract from different raw material. Journal of Chromatography A, 1120, 221-229. 

Application of modem analytical procedures and physical methods for structure determination. In studies of microbial metabolism, the advantages resulting from the requirement for only extremely small quantities of material needed for gas- and liquid-chromatographic quantification, coupled to mass spectrometric identification, can hardly be overestimated. 

Gas-chromatographic determination for plant materials liquid chromatography/mass spectrometric determination for water and soil... 

G. A. Van Der Doelen, K. J. Van Den Berg and J. J. Boon, Comparative chromatographic and mass spectrometric studies of triterpenoid varnishes fresh material and aged samples from paintings, Stud. Conserv., 43, 249 264 (1998). 

Christiaens B. et al., 2004. Fully automated method for the liquid chromatographic-tandem mass spectrometric determination of cyproterone acetate in human plasma using restricted access material for online sample clean-up, J Chromatogr A 1056. 

As a volatile material, bromomethane is readily determined by gas chromatographic analysis. The selectivity and sensitivity of detection are increased by the use of an electron capture detector or a halide-specific detector, both of which are very sensitive for organohalides such as bromomethane. Specificity in detection is achieved with mass spectrometric detectors. 

Many [M(dik)4] complexes are volatile, especially those that contain fluorinated diketonate ligands. Mass spectra and gas chromatographic behavior of several of these complexes have been studied (see Table 10). Isenhour and coworkers240 241 have employed fluorinated diketonates in mass spectrometric procedures for determination of Zr and Zr/Hf ratios in geological samples. The most intense peak in mass spectra of [M(dik)4] complexes is [M(dik)3]+. Sievers et al.242 have used gas chromatography of metal trifluoroacetylacetonates to separate Zr from Al, Cr and Rh. However, attempts to separate [Zr(tfacac)4] and [Hf(tfacac)4] by gas chromatography were unsuccessful. Zirconium and hafnium can be separated by solvent extraction procedures that employ fluorinated diketones.105 [M(dik)4] (M = Zr or Hf dik = acac, dpm, tfacac or hfacac) have been used as volatile source materials for chemical vapor deposition of thin films of the metal oxides.243,244... 

The hydride generation ICP-mass spectrometric technique [75] had a sensitivity of 6.4 ng/g selenium in plant material and was applied to digests of corn, kale and rice. In the isotope dilution mass spectrometric technique [77], the samples were spiked with 76-selenium solution and digested on a heating block at 150 °C with a mixture of nitric acid and hydrogen peroxide. Solid-phase microextraction was used to extract selenium from plant material prior to the gas chromatographic techniques [76]. See also Sects. 7.34.1 and 7.34.2. 

Investigations of lead speciation in various environmental samples have relied upon gas and liquid chromatographic separations coupled to mass spectrometric and atomic absorption spectrometric detectors. The combination of atomic absorption spectrometry with gas chromatography (GC-AAS) has proved to be the most widely applied technique. Sample types have included air, surface water, air particulates, sediments, grass, and clinical materials such as blood. A review of speciation analyses of organolead compounds by GC-AAS, with emphasis on environmental materials, was published (Lobinski et al., 1994). 

Gas chromatographic analysis using a 3-ft, 3% OV-17 column at 90°C indicated a purity of 92% (retention time was 3.2 min) with GC-mass spectrometric identification showing M+ mle 158 (27%) and the base peak (100%) at mle 113 (C6H902). The H NMR spectrum of undistilled material indicates impurities with resonances in the aliphatic region (8 1.5-1.0). The checkers recommend distillation of the crude product. 

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