Journal articles: 'Gas chromatography methods'

1

Venkatarmanan, Raman, and David J. Edwards. "Chemical Methods in Gas Chromatography." Journal of Pharmaceutical Sciences 74, no. 10 (July 1985): 1137–38. http://dx.doi.org/10.1002/jps.2600741034.

Full text

APA, Harvard, Vancouver, ISO, and other styles

2

Ray, N. H. "Gas chromatography. II. The separation and analysis of gas mixtures by chromatographic methods." Journal of Applied Chemistry 4, no. 2 (May 4, 2007): 82–85. http://dx.doi.org/10.1002/jctb.5010040205.

Full text

APA, Harvard, Vancouver, ISO, and other styles

3

Meng, Xin Xin, and Shu Lin Yang. "Comparison of Gas Chromatography and Liquid Chromatogram Detecting Pesticide Residue." Applied Mechanics and Materials 539 (July 2014): 113–16. http://dx.doi.org/10.4028/www.scientific.net/amm.539.113.

Full text

Abstract:

The existing methods of detecting pesticide residue include gas chromatography, high performance liquid chromatography, gas chromatograph-mass, liquid chromatograph-mass, capillary electrophoresis, radioimmunoassay, biosensor and rapid detection on the spot. The paper analyzes the comparison of gas chromatography and liquid chromatogram detecting pesticide residue, for achieving the development tendency and the future goal of analyzing pesticide residue.

APA, Harvard, Vancouver, ISO, and other styles

4

Hamilton-Kemp, T. R., J. H. Loughrin, and R. A. Andersen. "COLLECTION OF PLANT VOLATILES USING HEADSPACE METHODS." HortScience 25, no. 9 (September 1990): 1180c—1180. http://dx.doi.org/10.21273/hortsci.25.9.1180c.

Full text

Abstract:

Two methods for collecting headspace vapors produced by plant samples are presented. The first involves entraining volatiles in a stream of air and trapping the entrained compounds on a porous polymer such as Tenax. The volatiles are recovered from the trap by solvent extraction or heat desorption and analysed by gas chromatography. A second method entails removing headspace vapor above plant material with a gas-tight syringe and injecting the sample directly into the gas chromatograph. An evaluation of the usefulness of these techniques will be presented.

APA, Harvard, Vancouver, ISO, and other styles

5

Wong, Yong Foo, Constanze Hartmann, and Philip J Marriott. "Multidimensional gas chromatography methods for bioanalytical research." Bioanalysis 6, no. 18 (September 2014): 2461–79. http://dx.doi.org/10.4155/bio.14.186.

Full text

APA, Harvard, Vancouver, ISO, and other styles

6

van Ruth, Saskia M. "Methods for gas chromatography-olfactometry: a review." Biomolecular Engineering 17, no. 4-5 (May 2001): 121–28. http://dx.doi.org/10.1016/s1389-0344(01)00070-3.

Full text

APA, Harvard, Vancouver, ISO, and other styles

7

Villalobos, R. "Methods Development for On-Line Gas Chromatography." Journal of Chromatographic Science 28, no. 7 (July 1, 1990): 341–50. http://dx.doi.org/10.1093/chromsci/28.7.341.

Full text

APA, Harvard, Vancouver, ISO, and other styles

8

Schomburg, Gerhard. "Two-dimensional gas chromatography: Principles, instrumentation, methods." Journal of Chromatography A 703, no. 1-2 (June 1995): 309–25. http://dx.doi.org/10.1016/0021-9673(95)00190-x.

Full text

APA, Harvard, Vancouver, ISO, and other styles

9

Etxebarria, Nestor, Olatz Zuloaga, Maitane Olivares, Luis J. Bartolomé, and Patricia Navarro. "Retention-time locked methods in gas chromatography." Journal of Chromatography A 1216, no. 10 (March 2009): 1624–29. http://dx.doi.org/10.1016/j.chroma.2008.12.038.

Full text

APA, Harvard, Vancouver, ISO, and other styles

10

Mah, Christine, and Kevin B. Thurbide. "Acoustic methods of detection in gas chromatography." Journal of Separation Science 29, no. 12 (August 2006): 1922–30. http://dx.doi.org/10.1002/jssc.200500424.

Full text

APA, Harvard, Vancouver, ISO, and other styles

11

Isoherranen, Nina, and Stefan Soback. "Chromatographic Methods for Analysis of Aminoglycoside Antibiotics." Journal of AOAC INTERNATIONAL 82, no. 5 (September 1, 1999): 1017–45. http://dx.doi.org/10.1093/jaoac/82.5.1017.

Full text

Abstract:

Abstract Aminoglycosides are antimicrobial agents used frequently in treatment of human and animal diseases caused by aerobic, gram-negative bacteria. Because of the toxicity of these compounds, considerable effort has been attributed to analysis of aminoglycoside content in drug preparations, in serum and urine specimen in therapeutic drug monitoring, and in edible animal tissues in residue control. The present review emphasizes the analytical problems associated with aminoglycoside analysis. Screening methods based on microbiological and immunological procedures were briefly discussed. Gas chromatography and especially high-performance liquid chromatography appeared the most widely used chemical methods for the analysis of these compounds. Due to lack of volatility, chromophore, and hydrophility of aminoglycosides, most methods applied derivatization for enhancement of their chromatographic characteristics. The applicability and advantages of the various derivatization procedures were discussed in detail. A wide variety of detection methods, including mass spectrometry have been used. Packed column separation was generally used for gas chromatographic separation. In liquid chromatography, reversed phase, ion pair, ion exchange, and normal phase separation has been employed. Mass spectrometry, as a detection method, was discussed in detail. Extraction procedures from body fluids and tissues were emphasized. The performance and the operational conditions of the methods were described and detailed information of the data was provided also in table format.

APA, Harvard, Vancouver, ISO, and other styles

12

Sarajlija, H., N. Čukelj, G. Novotni D Mršić, M. Brnčić, and D. Ćurić. "Preparation of flaxseed for lignan determination by gas chromatography–mass spectrometry method." Czech Journal of Food Sciences 30, No. 1 (January 30, 2012): 45–52. http://dx.doi.org/10.17221/107/2010-cjfs.

Full text

Abstract:

Since 1980s, several methods for the determination of lignans in food samples have been developed depending on the types of lignans and foods analysed, but mostly on flaxseed as a reference food. In this work, specific steps in flaxseed preparation for lignan secoisolariciresinol analysis by gas chromatography-mass spectrometry method were examined. Ethanol extraction of lignan from defatted and non-defatted flaxseed before acid hydrolysis yielded significantly lower concentrations (5172 ± 49 μg/g; 5159 ± 83 μg/g, respectively), when compared to the direct acid hydrolysis (8566 ± 169 μg/g; 8571 ± 192 μg/g, respectively). In the analysed samples of defatted and dried flaxseed, no significant difference in lignan content was observed when compared to non-defatted flaxseed samples.  

APA, Harvard, Vancouver, ISO, and other styles

13

Rodriguez-Estrada, Maria Teresa, Arianna Costa, Marco Pelillo, Maria Fiorenza Caboni, and Giovanni Lercker. "Comparison of Cholesterol Oxidation Product Preparation Methods for Subsequent Gas Chromatographic Analysis." Journal of AOAC INTERNATIONAL 87, no. 2 (March 1, 2004): 474–80. http://dx.doi.org/10.1093/jaoac/87.2.474.

Full text

Abstract:

Abstract An evaluation was made of the stability of cholesterol hydroperoxides (CHPs) under the analytical conditions and preparation methods commonly used for determination and quantification of cholesterol oxidation products (COPs). CHPs were prepared by photoxidation and separated by silica thin-layer chromatography. CHPs were individually collected by normal-phase liquid chromatography and then subjected either to reduction or to cold saponification. The corresponding hydroxyl derivatives were generated by reduction, whereas cold saponification gave rise predominantly to 7-ketocholesterol. In another test, silylated and non-silylated CHPs were separately injected into a gas chromatograph at 310°C, collected, and re-injected into a gas chromatography-mass spectrometry system. The silylated CHPs were more stable than the non-silylated ones, giving 7-ketocholesterol, 7α-and 7β-hydroxycholesterol as main degradation products. Two unknown degradation peaks were detected in both silylated and nonsilylated CHPs, having 384 as main m/z fragment. The study of their mass spectra led to the conclusion that peaks A and B correspond to 6α- and 6β-hydroxycholesterol, respectively.

APA, Harvard, Vancouver, ISO, and other styles

14

Kataev, S. S., O. N. Dvorskaya, M. A. Gofenberg, A. V. Labutin, and A. B. Melentyev. "ANALYTICAL FEATURES OF SYNTHETIC MDMB(N)-073F CANNABIMIMETICS AND ITS MARKERS IN BIOLOGICAL MATERIAL." Pharmacy & Pharmacology 7, no. 4 (September 10, 2019): 184–97. http://dx.doi.org/10.19163/2307-9266-2019-7-4-184-197.

Full text

Abstract:

The aim of the research is to study both analytical features of synthetic MDMB(N)-073F cannabimimetics of indazole carboxamides group by gas chromatography methods combined with tandem mass spectrometry (GC-MS) and high performance liquid chromatography with high-resolution mass spectrometry (HPLC-HRMS) as well as characteristics of the major MDMB(N)-073F metabolite, its glucuronide and derivatives, using gas chromatography with mass-spectrometric (GC-MS) detection and high-performance liquid chromatography (HPLC) with MS/MS mass spectrometry (HPLC-MS/MS) in urine samples to be applied in expert practice, chemical-toxicological and forensic and chemical analyses.Materials and methods. To carry out the study, the following materials were used: plant-based objects with narcotic drugs withdrawn from illegal trafficking and applied to them;. urine samples to be studied under chemical-toxicological and forensic and chemical analyses. For solid-phase epitaxy, SampliQ EVIDEX TFE cartridges – 200 mg – 3 ml (Agilent, USA) were used for sample preparation; β-glucuronidase, Type HP-2, From Helix Pomatia, 100000 UA/ml (Sigma-ALDRICH CHEMI, Germany) was used for enzymatic hydrolysis. GC-MS/MS analysis was made using Agilent 7890 gas chromatograph with a tandem quadrupolar mass-spectrometer Agilent 7000 (Agilent, США); GC-MS analysis was carrid out using gas chromatograph Agilent 7820 with mass-selective detector Agilent 5975 (Agilent, USA); HPLC-HRMS research was made on liquid chromatograph Agilent 1260 with tandem hybrid high-resolution quadrupole-time-of-flight detector Agilent 6540 (Agilent, США); liquid chromatograph Agilent 1260 with Agilent 6460 (Agilent, USA) with tandem mass-spectrometer were used for making HPLC-MS/MS research.Results. The structure of MDMB(N)-073F compound has been confirmed and an exact mass of the protonated molecule corresponding to the chemical formula C19H27FN3O3 fixed by GC-MS/MS and HPLC-HRMS methods. Spectral characteristics of MDMB(N)-073F have been given. One of the branches in MDMB(N)-073F biotransformation in the human body found out by GC-MS and HPLC-MS/MS methods, is the ester decomposition with further conjugation of the resulting acid. The product interacting with glucuronic acid, is found to be the conjugate of major MDMB(N)-073F metabolite of the Ist phase in biotransformation. Metabolites appearing due to the ester decomposition and its conjugate with glucuronic acid, are recommended to be used as markers for synthetic MDMB(N)-073F cannabimimetics in the analysis by chromatographic methods; they can be used for regular screening of biological samples.Conclusion. The research results presented here, are the following: the analytical features characteristic for synthetic MDMB(N)-073F cannabimimetics found out by gas chromatography methods combined with tandem mass spectrometry (GC-MS/ MS) and liquid chromatography of hybrid high-resolution quadrupole-time-of-flight mass spectrometry (HPLC-HRMS), as well as characteristics of major MDMB(N)-073F metabolite, its glucuronide and derivatives with the use of gas chromatography with mass-spectrometric detection (GC-MS) and liquid chromatography combined with tandem mass spectrometry (HPLC-MS/MS) in urine samples to be applied in expert practice, chemical-toxicological, forensic and chemical analyses.

APA, Harvard, Vancouver, ISO, and other styles

15

Korytár, Peter, Hans-Gerd Janssen, Eva Matisová, and Udo A. Th Brinkman. "Practical fast gas chromatography: methods, instrumentation and applications." TrAC Trends in Analytical Chemistry 21, no. 9-10 (September 2002): 558–72. http://dx.doi.org/10.1016/s0165-9936(02)00811-7.

Full text

APA, Harvard, Vancouver, ISO, and other styles

16

Kolb, Bruno. "Headspace analysis and related methods in gas chromatography." TrAC Trends in Analytical Chemistry 4, no. 6 (June 1985): XXII—XXIII. http://dx.doi.org/10.1016/0165-9936(85)88014-6.

Full text

APA, Harvard, Vancouver, ISO, and other styles

17

Shkurdoda, S., D. Shynkarenko, V. Pasichnyk, K. Korol, and O. Posilskyi. "EXPERT STUDY OF ISONIAZIDE IN MEAT PRODUCTS." Criminalistics and Forensics, no. 66 (2021): 785–99. http://dx.doi.org/10.33994/kndise.2020.66.57.

Full text

Abstract:

The article deals with the recommendations for the detection of isoniazid in meat products, using the example of minced meat using physicochemical methods. This study does not lose its relevance over the years, due to the use of drugs for tuberculosis for poisoning homeless and domestic animals, in particular dogs, in different regions of Ukraine, the main active ingredient of which is isoniazid. The article describes a method for the extraction of isoniazid in food products of meat origin (minced meat, sausage), which presumably could or may be used to poison domestic animals, in particular dogs. Isoniazid was identified by the methods of qualitative color reactions, thin-layer chromatography, and gas chromatography with a mass-selective detector. The process of qualitative identification of isoniazid in foodstuffs that could or may be used to poison domestic animals, in particular dogs, includes: -the method of extraction and separation of interfering impurities, primarily fats, preliminary research by the method of qualitative analytical reactions; -studies by thin layer chromatography; -research by instrumental methods, in particular, gas chromatography with mass-selective detection. The method for extracting isoniazid from meat products described in the article is effective and allows you to get rid of interfering substances, especially fats. In addition, the method of gas chromatography with mass-selective detection has sufficient sensitivity and selectivity. It allows with a minimum number of interfering peaks of low intensity, determine the composition of isoniazid accurately. The specified list of instrumental base, methods and research techniques is not exhaustive. The examiner should be guided by the availability of relevant literature and the availability of appropriate analytical equipment (gas chromatograph, gas chromatograph with mass-selective detector, liquid chromatograph, liquid chromatograph with mass-selective detector, etc.). In accordance with this, it is necessary to use certain methods for studying substances. These methods are subject to mandatory verification before being used in the laboratory. The obtained research results allow us to recommend this technique for implementation in expert practice.

APA, Harvard, Vancouver, ISO, and other styles

18

Domínguez, José Antonio García, and José Carlos Díez-Masa. "Part B. Retention parameters in gas chromatograpy." Pure and Applied Chemistry 73, no. 6 (June 1, 2001): 969–92. http://dx.doi.org/10.1351/pac200173060969.

Full text

Abstract:

The paper presents a revision of terms in the IUPAC "Nomenclature for Chromatography", Pure and Applied Chemistry, 65, 819-872, 1993. The terms revised pertain to hold-up volumes in gas, liquid, and supercritical-fluid chromatography, as well as to basic retention parameters, especially in gas chromatography. A number of related and derived definitions are described, including definitions of the terms "chromatographic process" and "chromatographic phase system". A number of the original terms were found to be misleading or superfluous, including such terms as corrected retention time, net retention time, total retention volume (time), and specific retention volume at 0 °C, and their use is strongly discouraged In Part A, the concept of the hold-up volume in chromatography is discussed. The paper also compares methods described in the literature to determine the hold-up volume. In Part B, retention parameters in gas chromatography are discussed with the aim of (i) emphasizing the physical meaning of the terms and (ii) specifying the temperatures and pressures for the terms for gas volumes and flow rates. The appendix presents revised recommendations for the terminology of some items, as well as those that are not recommended.

APA, Harvard, Vancouver, ISO, and other styles

19

Zhan, Ping, Honglei Tian, Baoguo Sun, Yuyu Zhang, and Haitao Chen. "Quality Control of Mutton by Using Volatile Compound Fingerprinting Techniques and Chemometric Methods." Journal of Food Quality 2017 (2017): 1–8. http://dx.doi.org/10.1155/2017/9273929.

Full text

Abstract:

A method for chromatographic fingerprinting of flavor was established for the quality control of mutton. Twenty-five mutton samples that were chosen from twelve batches were investigated by gas chromatography-mass spectroscopy (GC-MS) and gas chromatography-olfactometry (GC-O). Spectral correlative chromatograms combined with GC-O assessment were employed, and 32 common odor-active compounds that characterize mutton flavor fingerprint were obtained. Based on the flavor chromatographic fingerprint data, principal component analysis (PCA) and partial least squares-discriminant analysis (PLS-DA) were designed and employed as chromatographic fingerprint methods. Defined categories were perfectly discriminated after PLS-DA was conducted on the fused matrix, demonstrating a 100% accurate classification. Fourteen constituents were further screened with PLS-DA to be the main chemical markers, and they were used to develop similar approaches for the determination of mutton quality and traceability. The flavor fingerprint of mutton established using SPME-GC-MS/O coupled with PLS-DA is appropriate for differentiating and identifying samples, and the procedure would be used in quality control.

APA, Harvard, Vancouver, ISO, and other styles

20

Roman, Itxaso, Maria Alonso, Luis Bartolome, and Rosa Alonso. "Headspace Gas Chromatography Methods and their Potential Industrial Applications." Current Chromatography 1, no. 2 (January 31, 2014): 100–121. http://dx.doi.org/10.2174/2213240601666140131235643.

Full text

APA, Harvard, Vancouver, ISO, and other styles

21

Rykowska, Iwona, and Wiesław Wasiak. "Stationary Phases for Complexation Gas Chromatography and Microextraction Methods." Israel Journal of Chemistry 56, no. 11-12 (September 14, 2016): 968–76. http://dx.doi.org/10.1002/ijch.201600064.

Full text

APA, Harvard, Vancouver, ISO, and other styles

22

McMahon, D. H. "Methods Development Guidelines for Chemical Derivatization in Gas Chromatography." Journal of Chromatographic Science 23, no. 9 (September 1, 1985): 426–28. http://dx.doi.org/10.1093/chromsci/23.9.426.

Full text

APA, Harvard, Vancouver, ISO, and other styles

23

Munir, Muhammad Abdurrahman, Muhammad Mukram Mohamed Mackeen, Lee Yook Heng, and Khairiah Haji Badri. "Study of Histamine Detection using Liquid Chromatography and Gas Chromatography." ASM Science Journal 16 (July 26, 2021): 1–9. http://dx.doi.org/10.32802/asmscj.2021.809.

Full text

Abstract:

Histamine is a heterocyclic amine shaped by decarboxylation of the histidine. It is a compound that lack chromophore and involatile. However, the detection of histamine is imperative due to the characteristic of histamine has given several disadvantages in food industry. This paper describes methods for histamine detection by employing high performance liquid chromatography and gas chromatography. The derivatization techniques required for both methods in order to increase the sensitivity of chromatography analysis. Two derivatizing agents were applied in this study such as 9-flourenilmethyl chloroformate (FMOC – Cl) for HPLC analysis whereas for GC analysis a N,O-bis (trimethylsilyl)acetamide (BSA) was used. Method validation was in accordance to Commission Decision 657/2002/CE. The validation of specificity, linearity, precision, accuracy, detection limit and quantitation limit results indicate that the methods were acceptable. The linear range for both methods were at 0.16 – 5.00 µg∙mL-1. The determination of histamine using GC showed the superiority of this instrument compared to HPLC. Method applicability was also checked on real sample namely mackerel in order to acquire a satisfactory recovery for both methods.

APA, Harvard, Vancouver, ISO, and other styles

24

Wunschel, David S., Angela M. Melville, Christopher J. Ehrhardt, Heather A. Colburn, Kristin D. Victry, Kathryn C. Antolick, Jon H. Wahl, and Karen L. Wahl. "Integration of gas chromatography mass spectrometry methods for differentiating ricin preparation methods." Analyst 137, no. 9 (2012): 2077. http://dx.doi.org/10.1039/c2an16186a.

Full text

APA, Harvard, Vancouver, ISO, and other styles

25

Jiang, Jin Yong, Gui E. Lu, Hao Nan Jia, Zhen Tao An, Qiang Ge, Shao Guang Wang, and Chen Chen. "Determination Methods for Storage Stability of Combustible Cartridge Case." Advanced Materials Research 1004-1005 (August 2014): 679–82. http://dx.doi.org/10.4028/www.scientific.net/amr.1004-1005.679.

Full text

Abstract:

The stabilizer content of aging combustible cartridge case (CCC) was measured by gas chromatography and chemical method. And the test results under different experimental conditions were analyzed. The results showed that the stabilizer content of the CCC decreased gradually with the aging time increased, which is in line with changes of stability of CCC. It is feasible to determine CCC stability by using gas chromatography.

APA, Harvard, Vancouver, ISO, and other styles

26

Burse, Virlyn W., Donald G. Patterson, John W. Brock, and Larry L. Needham. "Selected Analytical Methods Used At the Centers for Disease Control and Prevention for Measuring Environmental Pollutants in Serum." Toxicology and Industrial Health 12, no. 3-4 (May 1996): 481–98. http://dx.doi.org/10.1177/074823379601200320.

Full text

Abstract:

Blood serum is one of the more viable matrices used in assessing exposure to persistent environmental contaminants or their metabolites, especially those that are lipophilic. Analytic methods currently in use for this matrix usually involve liquid/liquid extraction followed by adsorption chromatography as a cleanup step, and low- or high-resolution gas chromatography with either electron-capture or mass spectrometric detection. The traditional analytic methods are labor intensive, have low sample throughput, and use excessive amounts of solvents and reagents. Two analytic approaches that address the requirements of modern laboratories more effectively are: 1) solid-phase extraction (SPE), used to analyze serum for several classes of compounds of environmental concern (e.g., polychlorinated biphenyls [PCBs], persistent pesticides, dioxins, furans, and coplanar polychlorinated biphenyls [CPCBs]), and 2) fast chromatography with a two-dimensional gas chromatographic system, which can be used in the determinative step for these types of analytes.

APA, Harvard, Vancouver, ISO, and other styles

27

Petkova, Mariana, and Nadezhda Sertova. "Detection of mycotoxins trough different analytical methods." Zbornik Matice srpske za prirodne nauke, no. 134 (2018): 43–54. http://dx.doi.org/10.2298/zmspn1834043p.

Full text

Abstract:

Mycotoxins are secondary metabolites produced by fungi which can affect a variety of feedstuffs. These compounds elicit toxicological effects which represent risk for both humans and animals. Their toxicity occurs at very low concentrations, therefore there is a need for sensitive and reliable methods for their detection. This review aims to evaluate classical and emerging methods for the analysis of mycotoxins concerning their advantages and disadvantages. Currently, several sensitive methods based on chromatographic or immunochemical technique are commercially available. Especially widely are used different chromatographic methods for quantitative determination of mycotoxins, including gas-chromatography (GC) and high-performance liquid chromatography (HPLC) coupled with ultraviolet, fluorescence or MS detectors. Liquid chromatography-tandem mass spectrometry (LC-MS/MS) is used as a promising technique for screening, identification and quantitative determination of a large number of mycotoxins. Immunometric assays, such as enzyme-linked immunosorbent assays (ELISA), are frequently used for screening purposes. On the other hand, a variety of emerging methods have been proposed. They are based on novel technologies, including immunochromatography (i.e. lateral flow devices), fluorescence polarization immunoassays (FPIA), infrared spectroscopy (FT-NIR), molecularly imprinted polymers (MIPs), and optical biosensors. In addition, during the last years, the highlight was put on nanoscale materials included in biosensors, which are some of the smart devices used for determination of mycotoxins.

APA, Harvard, Vancouver, ISO, and other styles

28

Yang, Liu, Molin Qin, Junchao Yang, Genwei Zhang, and Jiana Wei. "Review on stationary phases and coating methods of MEMs gas chromatography columns." Reviews in Analytical Chemistry 39, no. 1 (January 1, 2020): 247–59. http://dx.doi.org/10.1515/revac-2020-0102.

Full text

Abstract:

Abstract Gas chromatography (GC) is an important and widely used technique for separation and analysis in the field of analytical chemistry. Micro gas chromatography has been developed in response to the requirement for on-line analysis and on-site analysis. At the core of micro gas chromatography, microelectromechanical systems (MEMs) have the advantages of small size and low power consumption. This article introduces the stationary phases of micro columns in recent years, including polymer, carbon materials, silica, gold nanoparticles, inorganic adsorbents and ionic liquids. Preparation techniques ranging from classical coating to unusual sputtering of stationary phases are reviewed. The advantages and disadvantages of different preparation methods are analyzed. The paper introduces the separation characteristics and application progress of MEMs columns and discusses possible developments.

APA, Harvard, Vancouver, ISO, and other styles

29

Шелехова, Наталия Викторовна, Тамара Михайловна Шелехова, Любовь Ивановна Скворцова, and Наталья Валериевна Полтавская. "Methods gas chromatography, capillary electrophoresis, chromatography-mass spectrometry in analytical control of alcoholic beverages." Food processing industry, no. 9 (September 3, 2021): 63–64. http://dx.doi.org/10.52653/ppi.2021.9.9.028.

Full text

Abstract:

Разработаны, внедрены в практику аналитического контроля и применены в научных исследованиях инструментальные экспрессные методики определения химического состава продуктов, полупродуктов и отходов спиртового и ликероводочного производства. Получены новые экспериментальные данные, и выявлены закономерности кинетики биотехнологических процессов. Developed, implemented in the practice of analytical control and applied in scientific research instrumental express methods for determining the chemical composition of products, intermediates and waste of alcohol and distillery production. New experimental data are obtained and the regularities of the kinetics of biotechnological processes are revealed.

APA, Harvard, Vancouver, ISO, and other styles

30

OSZCZAPOWICZ, J. "ChemInform Abstract: Additivity Rules and Correlation Methods in Gas Chromatography." ChemInform 23, no. 5 (August 22, 2010): no. http://dx.doi.org/10.1002/chin.199205318.

Full text

APA, Harvard, Vancouver, ISO, and other styles

31

McClennen, William H., Richard M. Buchanan, Neil S. Arnold, Jacek P. Dworzanski, and Henk L. C. Meuzelaar. "Thermogravimetry/gas chromatography/mass spectrometry and thermogravimetry/gas chromatography/Fourier transform infrared spectroscopy: Novel hyphenated methods in thermal analysis." Analytical Chemistry 65, no. 20 (October 15, 1993): 2819–23. http://dx.doi.org/10.1021/ac00068a019.

Full text

APA, Harvard, Vancouver, ISO, and other styles

32

Liu, Guo Bin, Ning Wang, Qing Hao Wang, Tian Shu Hai, Chuan Zong Zhao, Gui Bin Hu, Hong Zhi Jiao, Chuan Bing Bi, and Hui Yan Cao. "Chromatographic Analysis of Oil-Based Electrical Equipment Discharge Failure." Applied Mechanics and Materials 602-605 (August 2014): 2953–57. http://dx.doi.org/10.4028/www.scientific.net/amm.602-605.2953.

Full text

Abstract:

Discharge of failure was the fault type are likely to occur in transformers, bushings, transformers, and the extent of damage to the equipment is a serious and direct impact on the stable operation of the system, first introduced the principle and gas chromatographic analysis its test methods, then gas chromatography equipment discharge failure is how to judge the conduct described. Through the analysis of transformer oil chromatographic method can be found as early as possible transformers and other equipment inside the existence of latent failures, thus chromatography is to oversee and guarantee the safe operation of an important means of transformer.

APA, Harvard, Vancouver, ISO, and other styles

33

Ali, Sana. "Green Analytical Methods in Analysis of Aflatoxins." Materials Science Forum 842 (February 2016): 172–81. http://dx.doi.org/10.4028/www.scientific.net/msf.842.172.

Full text

Abstract:

The detection and determination of aflatoxins at nanogram level is important from human health point of view. Aflatoxins exhibit acute toxicity demonstrating teratogenic, mutagenic and carcinogenic effects. Amongst the available aflatoxins, B1, B2, G1, G2, M1 and M2 have been the more frequently analysed aflatoxins by chromatographic, spectroscopic and immuochemical methods. Because of the presence of aflatoxins at trace level in food and feedstuff used for human and animal consumption, new analytical methods have been designed for sensitive and selective detection and quantification of aflatoxins. Each of the employed analytical methods, described herein, such as thin layer chromatography, high performance liquid chromatography, gas chromatography and immunochemical methods, among others, has inherent merits and demerits in aflatoxins analysis. This chapter critically examines each of the analytical methods currently in use in the analysis of aflatoxins. Deviating from the earlier approaches, this chapter focuses on the need of methodologies that have negligible environmental impact. Though most of the existing methods are highly sensitive and reasonably safer to use but still there is the need of development of new green methodologies focusing on the reduction of solvent consumption, replacement of environmentally hazardous solvents with more benign alternatives, miniaturization of instrumentation and solvent-free sample preparation.

APA, Harvard, Vancouver, ISO, and other styles

34

Lee, Hing-Biu. "Review of Analytical Methods for the Determination of Nonylphenol and Related Compounds in Environmental Samples." Water Quality Research Journal 34, no. 1 (February 1, 1999): 3–36. http://dx.doi.org/10.2166/wqrj.1999.002.

Full text

Abstract:

Abstract Analytical methods published in the last 20 years for the extraction, chromato-graphic separation, and quantification of alkylphenol ethoxylates (APEO) and related compounds in environmental samples are reviewed. Examples of various isolation and preconcentration techniques for water, effluent, sediment and sludge are presented. This includes procedures from the classical liquid-liquid and Soxhlet extraction to the up-to-date solid phase and supercritical fluid extraction. Chromatographic separation of APEO by normal and reversed phase liquid chromatography (LC) and capillary column gas chromatography (GC) is compared. A variety of quantification methods involving the common LC and GC detectors as well as various mass spectrometric techniques are also discussed.

APA, Harvard, Vancouver, ISO, and other styles

35

Shao, Bing, Hui Li, Jianzhong Shen, and Yongning Wu. "Nontargeted Detection Methods for Food Safety and Integrity." Annual Review of Food Science and Technology 10, no. 1 (March 25, 2019): 429–55. http://dx.doi.org/10.1146/annurev-food-032818-121233.

Full text

Abstract:

Nontargeted workflows for chemical hazard analyses are highly desirable in the food safety and integrity fields to ensure human health. Two different analytical strategies, nontargeted metabolomics and chemical database filtering, can be used to screen unknown contaminants in food matrices. Sufficient mass and chromatographic resolutions are necessary for the detection of compounds and subsequent componentization and interpretation of candidate ions. Analytical chemistry–based technologies, including gas chromatography–mass spectrometry (GC-MS), liquid chromatography–mass spectrometry (LC-MS), nuclear magnetic resonance (NMR), and capillary electrophoresis–mass spectrometry (CE-MS), combined with chemometrics analysis are being used to generate molecular formulas of compounds of interest. The construction of a chemical database plays a crucial role in nontargeted detection. This review provides an overview of the current sample preparation, analytical chemistry–based techniques, and data analysis as well as the limitations and challenges of nontargeted detection methods for analyzing complex food matrices. Improvements in sample preparation and analytical platforms may enhance the relevance of food authenticity, quality, and safety.

APA, Harvard, Vancouver, ISO, and other styles

36

Zumwalt, Robert W., Jean Desgres, Kenneth C. Kuo, James E. Pautz, and Charles W. Gehrke. "Amino Acid Analysis by Capillary Gas Chromatography." Journal of AOAC INTERNATIONAL 70, no. 2 (March 1, 1987): 253–62. http://dx.doi.org/10.1093/jaoac/70.2.253.

Full text

Abstract:

Abstract Two developments have enabled major advancements in the use of capillary gas chromatography (GC), the result being its much more widespread use in investigations on a broad range of chemical and biological problems. The 2 technological developments were the introduction of fused silica capillary columns and the development of immobilized stationary phases for capillary GC columns. Because fused silica columns with immobilized stationary phases of varying polarities are offered by numerous vendors of chromatographic equipment, they have become widely used for many analytical tasks. We conducted a study to compare the effectiveness of commercially available fused silica capillary columns with the classical ion-exchange method in the separation and quantitation of amino acids. We selected the /V-trifluoroacetyl (TFA) n-butyl and the A'-heptafloorobutyryl (HFB) isobutyl ester derivatives for this study because of the extensive research and application of these derivatives during the past 20 years. The amino acid content of hydrolysates of 5 materials was measured: ribonuclease,β-lactoglobulin, lysozyme, soybean meal, and a commercial poultry feed. Single 6N HC1 hydrolysates of each material were prepared to minimize sample preparation differences, and 3 independent analyses of each hydrolysate were made by each of 3 techniques: the N-TFA n-butyl and N-HFB isobutyl ester methods using capillary gas chromatography and the ion-exchange chromatographic method using a Beckman 121 M amino acid analyzer. Our results clearly demonstrate that capillary GC analysis of amino acids using fused silica bonded-phase columns provides data with good precision and in general excellent agreement with ion-exchange analyses.

APA, Harvard, Vancouver, ISO, and other styles

37

LLOVERA, MONTSERRAT, REMEI VILADRICH, MERCÈ TORRES, and RAMON CANELA. "Analysis of Underivatizated Patulin by a GC-MS Technique." Journal of Food Protection 62, no. 2 (February 1, 1999): 202–5. http://dx.doi.org/10.4315/0362-028x-62.2.202.

Full text

Abstract:

An alternative approach based on the use of gas chromatography-mass spectrometry (GC-MS) is used to confirm the presence of patulin in apple juice. In the gas chromatography (GC) methods previously described, derivatization of patulin was always necessary in order to achieve good chromatographic detection. The use of electronic pressure control (EPC) and on-column injection avoids the need for patulin derivatization and allows a sensitive analysis of patulin. A detection limit of 4 μg/liter in apple juice can be attributed to the method.

APA, Harvard, Vancouver, ISO, and other styles

38

Krylov, V. А., and Т. G. Sorochkina. "The determination of organic substances impurities in sodium nitrate by the methods of gas chromatography and gas chromatography - mass-spectrometry." Аналитика и контроль 19, no. 2 (2015): 208–13. http://dx.doi.org/10.15826/analitika.2015.19.2.012.

Full text

APA, Harvard, Vancouver, ISO, and other styles

39

Veijanen, A., E. Kolehmainen, R. Kauppinen, M. Lahtiperä, and J. Paasivirta. "Methods for the Identification of Tainting Terpenoids and other Compounds from Algae." Water Science and Technology 25, no. 2 (January 1, 1992): 165–70. http://dx.doi.org/10.2166/wst.1992.0048.

Full text

Abstract:

Off-flavour compounds produced by algae in freshwater ecosystems were studied for their structure using integrated sensory and spectroscopic methods: mass spectrometry (MS), nuclear magnetic resonance (NMR) and Fourier transform infrared (FTIR). Both solvent extraction and thermal desorption were used to isolate and to introduce the compounds into gas chromatography/mass spectrometry (GC/MS) and gas chromatography/Fourier transform infrared (GC/FTIR) systems. Ten ng of a terpenoid compound gave a readable IR spectrum. For 1H NMR studies the compounds were collected directly into NMR solvent by preparative gas chromatography. About 5 µg of a monoterpenoid compound was needed for a reliable 1H NMR spectrum. The mass spectral data indicated that the series of odorous substances detected by GC were terpenoid hydrocarbons and a later eluting series of compounds were sesquiterpene alcohols. In addition, one compound with an intense off-odour (aromatic, nitrogen containing compound) and some tainting carboxylic acids (derived from a starch factory) were detected.

APA, Harvard, Vancouver, ISO, and other styles

40

Lu, Gui E., Jin Yong Jiang, and Wen Ping Chang. "Study on the Methods Evaluating the Stability of a New Type of Energetic Material." Advanced Materials Research 287-290 (July 2011): 618–21. http://dx.doi.org/10.4028/www.scientific.net/amr.287-290.618.

Full text

Abstract:

171 propellant is a new type of energetic material, extensive research indicates that the traditional methods evaluating the stability of this propellant are unsuitable. So in this article, the stability of this material was studied by aging test, methyl-violet test and gas phase chromatography test. The results show that gas phase chromatography test is feasible for evaluating the stability of this material, but methyl-violet test is unsuitable.

APA, Harvard, Vancouver, ISO, and other styles

41

Headley, John V., Phillip M. Fedorak, and Leslie C. Dickson. "A Review of Analytical Methods for the Determination of Sulfolane and Alkanolamines in Environmental Studies." Journal of AOAC INTERNATIONAL 85, no. 1 (January 1, 2002): 154–62. http://dx.doi.org/10.1093/jaoac/85.1.154.

Full text

Abstract:

Abstract Sulfolane and alkanolamines are used extensively in the processing of sour natural gases. Over many years of operation, there have been inadvertent leaks of these chemicals to groundwater and wetlands surrounding gas processing facilities, leading to uptake by vegetation. Because sulfolane and alkanolamines are extremely water-soluble, their analysis has presented challenges, particularly requirements for suitable extraction from biological matrixes and soil, along with sensitive detection using commonly available instrumentation. Analytical methods usually use gas chromatography or liquid chromatography with a variety of detector systems. Sample preparation techniques may include extraction with organic solvents, water, or a combination of these. In some cases, direct aqueous injections have been used. Derivatization of alkanolamines has been used to improve the chromatographic separations and detection. More recent procedures, using positive-ion electrospray ionization mass spectrometry (MS), have been useful for the confirmation of uptake of the alkanolamines and transformation products by wetland vegetation. Future developments will likely center on further MS analyses for identification of metabolites and transformation products in aquatic environments.

APA, Harvard, Vancouver, ISO, and other styles

42

Durand, J. P., J. J. Beboulene, A. Ducrozet, A. Bre, and S. Carbonneaux. "Improvement of Simulated Distillation Methods by Gas Chromatography in Routine Analysis." Oil & Gas Science and Technology 54, no. 4 (July 1999): 431–38. http://dx.doi.org/10.2516/ogst:1999038.

Full text

APA, Harvard, Vancouver, ISO, and other styles

43

Christie, William W. "Gas chromatography-mass spectrometry methods for structural analysis of fatty acids." Lipids 33, no. 4 (April 1998): 343–53. http://dx.doi.org/10.1007/s11745-998-0214-x.

Full text

APA, Harvard, Vancouver, ISO, and other styles

44

Huang, Jan-Chan. "Methods to determine solubility parameters of polymers using inverse gas chromatography." Journal of Applied Polymer Science 91, no. 5 (2004): 2894–902. http://dx.doi.org/10.1002/app.13533.

Full text

APA, Harvard, Vancouver, ISO, and other styles

45

Merritt, Dawn A., W. A. Brand, and J. M. Hayes. "Isotope-ratio-monitoring gas chromatography-mass spectrometry: methods for isotopic calibration." Organic Geochemistry 21, no. 6-7 (June 1994): 573–83. http://dx.doi.org/10.1016/0146-6380(94)90003-5.

Full text

APA, Harvard, Vancouver, ISO, and other styles

46

Dixon, A. G., and Y. H. Ma. "A comparison of moment methods for non-isobaric gas chromatography columns." Chemical Engineering Science 43, no. 6 (1988): 1297–302. http://dx.doi.org/10.1016/0009-2509(88)85103-0.

Full text

APA, Harvard, Vancouver, ISO, and other styles

47

Baranov, Yu, V. Demchenko, Ie Zajets, and S. Olszewski. "Herbicides from the group of nitrodiphenyl ethers: applications in Ukraine, control methods, methods for determination of oxifluorphene residues in soybean grain and oil." Zurnal Hromatograficnogo tovaristva 20, no. 66 (February 18, 2021): 15–23. http://dx.doi.org/10.15407/zht2020.66.015.

Full text

Abstract:

A review of analytical methods for the determination of herbicide residues from the group of nitrodiphenyl ethers in the environment and agricultural products, developed and validated a method for oxyfluorfen determination in soybean grain and oil method GC/ECD, which meets regulatory requirements and solves the problem of toxicant control in the above matrices. The developed method uses modern methods of sample preparation, identification and quantification of oxyfluorfen (selective extraction, capillary gas-liquid chromatography (GC/ECD GC/MS). The method is validated according to EU requirements) (SANTE/12682/2019 quality control and analytical validation procedures for pesticide residues analysis in food and feed). Key words: gas-liquid chromatography, mass spectrometry, herbicides, nitrodiphenyl ethers, control, residual amounts.

APA, Harvard, Vancouver, ISO, and other styles

48

Kholin, Andrey Y., Elena E. Finkelshtein, and Svetlana V. Kurbatova. "Characteristic of stationary phases for gas chromatography." Butlerov Communications 61, no. 1 (January 31, 2020): 58–66. http://dx.doi.org/10.37952/roi-jbc-01/20-61-1-58.

Full text

Abstract:

The methods of preferred stationary phases choosing the used in gas-liquid chromatography are analyzed. It is shown that in the literature, such criteria as selectivity, sorption capacity, thermal stability, reproducibility of properties, operating temperature range, etc. are used as criteria for choosing suitable stationary phases. One of the most used methods for characterizing stationary phases is their classification using chromatographic polarity based predominantly on the values of polarity factors proposed by Rorschneider and Mc Reynolds. The basis of these systems is the characterization of various types of intermolecular interactions into which stationary phases can enter, using a set of standard substances. The system of Rorschneider-McReynolds polarity factors is also the basis of the spectral approach to identifying the components of complex mixtures, the essence of which is to use the combination of physicochemical characteristics of the sorbate and sorbent, which allows to establish the structure of sorbate molecules based on their different ability to be sorbed by stationary phases of different chemical nature. The spectral approach is applied to the characterization of weakly polar stationary phases of various chemical nature. It was shown that despite the close chromatographic polarity of the stationary phases, the retention of substances belonging to different classes of compounds can significantly differ and be determined by the values of descriptors characterizing the types of intermolecular interactions and the tendency of the stationary phases to a certain type. Spectra of 5 stationary phases obtained using the Rorschneider, Mac-Reynolds, and Lafffort solubility factors are presented. It was established that the possibility of preferential retention of sorbates of various chemical nature is determined by the ratio between the values of these descriptors. The possibility of choosing the corresponding stationary phases for the selective separation of sorbates of various chemical nature is shown.

APA, Harvard, Vancouver, ISO, and other styles

49

Grosjean, E., and D. Grosjean. "Comparison of Gas Chromatography and Liquid Chromatography Methods for Measuring Low Levels of Cyclohexanone in Air." International Journal of Environmental Analytical Chemistry 62, no. 4 (April 1996): 311–21. http://dx.doi.org/10.1080/03067319608026251.

Full text

APA, Harvard, Vancouver, ISO, and other styles

50

Fišerová, H., Z. Mikušová, and M. Klemš. "Estimation of ethylene production and 1-aminocyclopropane-1-carboxylic acid in plants by means of gas chromatography." Plant, Soil and Environment 54, No. 2 (February 7, 2008): 55–60. http://dx.doi.org/10.17221/2782-pse.

Full text

Abstract:

The paper deals with problems associated with preparation and collection of samples when estimating the production of ethylene and content of ACC (1-aminocyclopropane-1-carboxylic acid) in plants by means of gas chromatography. A proper method of sampling can significantly influence not only the reliability of obtained data but also their interpretation. Attention was paid to cultivation of plant material, sampling vessels, conditions of ethylene production, sampling procedure, and storage of gaseous samples. The estimation of ACC as a precursor of ethylene is more laborious but it supplements the information about the endogenous level of ethylene in a given part of the plant organism. The authors describe the sampling procedure, methods of sample preservation, extraction and purification, and also the method of oxidation of ACC to ethylene. In the final part of this study the authors evaluate the time consumption and difficulty of individual methods and describe their advantages and disadvantages as compared with other, alternative methods.

APA, Harvard, Vancouver, ISO, and other styles

Journal articles on the topic 'Gas chromatography methods'

Create a spot-on reference in APA, MLA, Chicago, Harvard, and other styles