Characterization of the organic contamination pattern of a hyper-saline ecosystem by rapid screening using gas chromatography coupled to high-resolution time-of-flight mass spectrometry

The performance of gas chromatography coupled to high-resolution time-of-flight mass spectrometry (GC-HRTofMS) for characterizing geochemical biomarkers from sediment samples was evaluated. Two approaches to obtain the geochemical biomarkers were tested: (1) extraction with organic solvent and subsequent derivatization and (2) in-situ derivatization thermal desorption. Results demonstrated that both approaches can be conveniently applied for simultaneous characterization of many geochemical biomarkers (alkanes, alkanols, sterols, and fatty acids), avoiding conventional time-consuming purification procedures. GC-HRTofMS reduces both sample preparation time and the number of chromatographic runs compared to traditional methodologies used in organic geochemistry. Particularly, the approach based on in-situ derivatization thermal desorption represents a very simple method that can be performed in-line employing few milligrams of sediment, eliminating the need for any sample preparation and solvent use. The high resolving power (m/Δm50% 25,000) and high mass accuracy (error ≤ 1 ppm) offered by the “zig-zag” time-of-flight analyzer were indispensable to resolve the complexity of the total ion chromatograms, representing a high-throughput tool. Extracted ion chromatograms using exact m/z were useful to eliminate many isobaric interferences and to increase significantly the signal to noise ratio. Characteristic fragment ions allowed the identification of homologous series, such as alkanes, alkanols, fatty acids, and sterols. Polycyclic aromatic hydrocarbons were also identified in the samples by their molecular ions. The characterization of geochemical biomarkers along a sedimentary core collected in the area of Valo Grande Channel (Cananéia-Iguape Estuarine-Lagunar System (São Paulo, Brazil)) provided evidences of environmental changes. Sediments deposited before opening of channel showed dominance of biomarkers from mangrove vegetation, whereas sediments of the pos-opening period showed an increase of biomarkers from aquatic macrophyte (an invasive vegetation).

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Characterization of Chemical Composition of Pericarpium Citri Reticulatae Volatile Oil by Comprehensive Two-Dimensional Gas Chromatography with High-Resolution Time-of-Flight Mass Spectrometry

Evidence-based Complementary and Alternative Medicine ◽

10.1155/2013/237541 ◽

2013 ◽

Vol 2013 ◽

pp. 1-11 ◽

Cited By ~ 7

Author(s):

Kunming Qin ◽

Lijuan Zheng ◽

Hao Cai ◽

Gang Cao ◽

Yajing Lou ◽

...

Keyword(s):

Mass Spectrometry ◽

Gas Chromatography ◽

Chemical Composition ◽

High Resolution ◽

Time Of Flight ◽

Volatile Oil ◽

Two Dimensional ◽

Resolution Time ◽

Flight Mass Spectrometry

Pericarpium Citri Reticulatae (Chenpi in Chinese) has been widely used as an herbal medicine in Korea, China, and Japan. Chenpi extracts are used to treat indigestion and inflammatory syndromes of the respiratory tract such as bronchitis and asthma. This thesis will analyze chemical compositions of Chenpi volatile oil, which was performed by comprehensive two-dimensional gas chromatography with high-resolution time-of-flight mass spectrometry (GC × GC-HR-TOFMS). One hundred and sixty-seven components were tentatively identified, and terpene compounds are the main components of Chenpi volatile oil, a significant larger number than in previous studies. The majority of the eluted compounds, which were identified, were well separated as a result of high-resolution capability of the GC × GC method, which significantly reduces, the coelution.β-Elemene is tentatively qualified by means of GC × GC in tandem with high-resolution TOFMS detection, which plays an important role in enhancing the effects of many anticancer drugs and in reducing the side effects of chemotherapy. This study suggests that GC × GC-HR-TOFMS is suitable for routine characterization of chemical composition of volatile oil in herbal medicines.

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Rapid analysis of multiple pesticide residues in fruit-based baby food using programmed temperature vaporiser injection–low-pressure gas chromatography–high-resolution time-of-flight mass spectrometry

Journal of Chromatography A ◽

10.1016/j.chroma.2007.12.009 ◽

2008 ◽

Vol 1186 (1-2) ◽

pp. 281-294 ◽

Cited By ~ 85

Author(s):

Tomas Cajka ◽

Jana Hajslova ◽

Ondrej Lacina ◽

Katerina Mastovska ◽

Steven J. Lehotay

Keyword(s):

Mass Spectrometry ◽

Gas Chromatography ◽

High Resolution ◽

Pesticide Residues ◽

Time Of Flight ◽

Rapid Analysis ◽

Baby Food ◽

Resolution Time ◽

Flight Mass Spectrometry ◽

Multiple Pesticide Residues

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“Analysis of pesticide residues in fruits and vegetables using gas chromatography-high resolution time-of-flight mass spectrometry”

Analytical Methods ◽

10.1039/c4ay02284j ◽

2015 ◽

Vol 7 (5) ◽

pp. 2162-2171 ◽

Cited By ~ 10

Author(s):

Noelia Belmonte Valles ◽

Samanta Uclés ◽

Natalia Besil ◽

Milagros Mezcua ◽

Amadeo R. Fernández-Alba

Keyword(s):

Mass Spectrometry ◽

Gas Chromatography ◽

High Resolution ◽

Pesticide Residues ◽

Fruits And Vegetables ◽

Time Of Flight ◽

Automatic Method ◽

Operational Parameters ◽

Resolution Time ◽

Flight Mass Spectrometry

This work reports a study on the operational parameters and development of a rapid automatic method for determining pesticide residues in fruit and vegetables using gas chromatography-high resolution time-of-flight mass spectrometry.

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