A method for quantitatively analyzing 11 amide alkaloids in tobacco leaves using gas chromatography-tandem mass spectrometry, comprises: soaking with a sodium hydroxide solution so as to free amide alkaloids from a tobacco powder sample matrix, transferring target compounds into an ether layer through extraction with methyl tertiary butyl ether, concentrating methyl tertiary butyl ether extraction liquids for analysis with gas chromatography-tandem mass spectrometry, inputting chromatographic peak areas obtained by an instrument into standard calibration curve fitting equations of the corresponding amide alkaloids to obtain the concentrations of the corresponding target compounds, and converting the concentrations to obtain the contents of the corresponding amide alkaloids in the tobacco leaves. The method can quantitatively analyze the 11 amide alkaloids at the same time, and has the advantages of simpleness, rapidness, stability and the like.

A method of detecting a seizure includes collecting volatile organic compounds with a collector material of a collector; separating a mixture of the volatile organic compounds into its constituent chemicals with a gas chromatography column; ionizing the constituent chemicals to create ionized chemicals and detecting the ionized chemicals; and analyzing the ionized chemicals to identify seizure-indicative volatile organic compounds.

The present invention relates to a dianhydride analysis method, which can reliably analyze a dianhydride having high reactivity and low solubility. In addition, the present invention can analyze the structure of impurities by separating the impurities on the basis of having a similar retention time in HPLC analysis, and can analyze the purity of the dianhydride with or without chromophores.

The disclosure provides a method for analyzing compounds extracted from Cannabis. The method comprises extracting cannabinoids or terpenes from a sample using a C.sub.1-C.sub.4 alcohol or C.sub.5-C.sub.8 solvent as an extraction solvent to produce a supernatant, drying the supernatant to produce a dried extract, and dissolving the dried extract in a second C.sub.1-C.sub.4 alcohol or C.sub.5-C.sub.8 solvent, separating the cannabinoids or terpenes by gas chromatography using a capillary column with hydrogen as a carrier gas; and detecting the cannabinoids or terpenes using a mass spectrometer. The disclosure also provides a method of determining an effect of one or more Cannabis-derived compounds on intracellular calcium concentration in a cell using a microfluidic device.

In the present invention, among blood metabolites, amino acids, organic compounds and oxylipins that were statistically significantly differentiated from the control group, were selected from type 2 diabetes patients. Specifically, asparagine, aspartic acid, glutamic acid, cysteine, lysine, citric acid, and uric acid, and 12-oxo ETE, 15-oxo ETE, 9-oxo ODE, and 20-carboxy leukotriene B4, which are oxylipins, were confirmed to have cutoff values of AUC>0.7. In addition, the blood metabolites showed a significant difference between a DME patient group and a non-DME patient group, and thus were confirmed to be usable for accurate diagnosis of DME.

The present specification relates to a method for analyzing deuterated benzene by gas chromatography, and preparing a deuterated compound using deuterated benzene selected based on the analyzed data.

This invention relates to a micro-device for detecting volatile compounds comprising: an input (E) and an output (S); collection means (2) for taking a gas sample containing at least one compound to be detected; sampling means enabling a gas volume of 100 mL or less to be sampled, arranged after the collection means; injection means (3) of said gas sample; separation means (5) of the compound to be detected in the gas sample; compound detection means (6); and a gas circulation circuit (1) located downstream of the collection means and passing through the sampling means, injection means (3), separation means (5) and detection means (6);

characterized in that the gas circulation circuit (1) has a volume of between 0.2 cm.sup.3 and 2.0 cm.sup.3.

Samples are analyzed in a system that includes a gas chromatography column for separating components in a sample and a spectrometry system for detecting these components. An interferent present in the sample, water for example, flows through the column and the sample cell of the spectrometry system before beginning the analysis of analytes.

A wearable health monitoring device includes a band configured to attach the wearable health monitoring device to a user's body; a VOC detection device configured to collect and analyze volatile organic compounds given off from the user's skin to identify specific health-indicative volatile organic compounds indicative of a health condition; and a biomarker sensor configured to detect a biomarker of the user.

The present invention relates to methods of determining the purity of a sample of 3,4-diaminopyridine comprising determining the presence, absence, or amount of a dimer of 3,4-diaminopyridine or a dimer of 3,4-diaminopyridine in the form of a salt, solvate or complex or a combination thereof. The invention also relates to methods of detecting and quantitating degradation in a sample of 3,4-diaminopyridine. Dimers of 3,4-diaminopyridine and methods of making and isolating the same are also provided.