AIMC Topic: Gas Chromatography-Mass Spectrometry

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Quantitative analysis of menthol in human urine using solid phase microextraction and stable isotope dilution gas chromatography-mass spectrometry.

Journal of chromatography. B, Analytical technologies in the biomedical and life sciences
To accurately measure menthol levels in human urine, we developed a method using gas chromatography/electron ionization mass spectrometry with menthol-d stable isotope internal standardization. We used solid phase microextraction (SPME) headspace sam...

GC-MS Metabolomics Identifies Metabolite Alterations That Precede Subclinical Mastitis in the Blood of Transition Dairy Cows.

Journal of proteome research
The objectives of this study were to determine alterations in the serum metabolites related to amino acid (AA), carbohydrate, and lipid metabolism in transition dairy cows before diagnosis of subclinical mastitis (SCM), during, and after diagnosis of...

Method for the Determination of Carbonyl Compounds in E-Cigarette Aerosols.

Journal of chromatographic science
Low levels of thermal degradation products such as carbonyls (formaldehyde, acetaldehyde, acrolein, crotonaldehyde) have been reported in e-cigarette aerosols. The collection and analysis of e-cigarette aerosol carbonyls are often adapted from method...

Classification of the fragrant styles and evaluation of the aromatic quality of flue-cured tobacco leaves by machine-learning methods.

Journal of bioinformatics and computational biology
During commercial transactions, the quality of flue-cured tobacco leaves must be characterized efficiently, and the evaluation system should be easily transferable across different traders. However, there are over 3000 chemical compounds in flue-cure...

GC-MS analysis of the designer drug α-pyrrolidinovalerophenone and its metabolites in urine and blood in an acute poisoning case.

Forensic science international
α-Pyrrolidinovalerophenone (α-PVP) is a synthetic cathinone belonging to the group of "second generation" pyrrolidinophenones that becomes more and more popular as a designer psychostimulant. Here we provide toxicological analytical support for a sev...

Potential of atmospheric pressure chemical ionization source in gas chromatography tandem mass spectrometry for the screening of urinary exogenous androgenic anabolic steroids.

Analytica chimica acta
The atmospheric pressure chemical ionization (APCI) source for gas chromatography-mass spectrometry analysis has been evaluated for the screening of 16 exogenous androgenic anabolic steroids (AAS) in urine. The sample treatment is based on the strate...

Study of the sensory profile of Coffea canephora through malting/fermentation using HS-SPME-GC-MS and synthetic sampling combined with random forest.

Food chemistry
The sensory attributes of Coffea canephora beverages depend on the chemical composition of the bean, especially to the content of volatile organic compounds (VOCs). However, the relative abundance of these compounds may vary with the stage of bean ma...

Characterize the dynamic changes of volatile compounds during the roasting process of Wuyi rock tea (Shuixian) integrating GC-IMS and GC × GC-O-MS combined with machine learning.

Food chemistry
Understanding aroma compounds' changes during Shuixian roasting is vital for scientific guidance. This study used gas chromatography-ion mobility spectrometry (GC-IMS) and two-dimensional gas chromatography-olfactory-mass spectrometry (GC × GC-O-MS) ...