Gas chromatography

Chromatography is a separation method used to help identify mixtures. One common form of chromatography is gas chromatography. This type of chromatography will usually use a gas as the mobile phase, and a liquid as the stationary phase (“Gas Chromatography”). A gas chromatograph is comprised of some vital components, which include: the carrier gas, flow controller, injector port, column, column oven, detector, and recorder (“Gas Chromatography”). The purpose of this lab was for an unknown accelerant to be identified using GCMS. Though this was not possible as the GCMS was not available. Instead, data samples were given for the use of determining the unknown accelerant. Methods Though the GCMS instrument was not used, there are procedures which…

Gas chromatography (like any other chromatography) is a separation technique in which the mobile phase is a gas. This technique is applied for the separation of volatile substances. This method separates a mixture into its components and is used to measure the concentration as well as it identifies the components. GC creates a time separation rather than physical separation which means that the components are separated in time. After they are detected, a chromatogram is generated. Each peak in…

Introduction: The main purpose of this experiment was to take the Gas Chromatography/ Mass Spectrum part of the “Analysis of US bills for cocaine using gas chromatography / mass spectrometry” lab and improve upon the gas chromatographic results. This would be done by finding a way to separate the peaks of cocaine and doxepin. The lab done previously showed the use of two different methods to obtain samples of cocaine and doxepin for spiked dollar bills. The two extraction methods were…

Part A Gas Chromatography What is it? Gas chromatography is a variation of chromatography used in analytical chemistry for separating and analysing components that can be vaporised without decomposition ("Gas Chromatography", 2016). This technique involves using a gas as the mobile phase. There are two types of gas chromatography: • Gas-solid chromatography – separates substances on the basis of their different strengths of adsorption on the solid • Gas-liquid chromatography – separates…

Gas chromatography (GC) is a chromatography technique where the separation of individual components (called analytes) from a sample relies on their differing distribution between the mobile phase and a stationary phase. The mobile phase is what carries the analyte (components being analysed) through the stationary phase and in GC, it is an inert gas, (usually helium or nitrogen). The gas must be inert so it will not react with the samples to give a false reading. The stationary phase is the…

Previously, for the first part of the experiment, it was hypothesized that the retention times of the eluates were invariably associated with the polarity of the compound; the more non-polar the compound, the faster it would be eluted out of the gas chromatogram. It was also hypothesized that the retention times decreased as the temperature in the gas column increased. In the first part of the experiment the relationship between the temperature and retention time, and the non-polarity of the…

In this lab, a hexane and octane mixture was purified, through distillation, to pure octane. The distillation could be completed because part of the solution, hexane, had a lower boiling point than the other, octane, allowing it to evaporate out. Throughout the experiment, four samples were taken and tested by gas chromatography. Gas Chromatography, or GC, was used to analysis the components of each fraction taken during the experiment. Upon looking at the data, the presence of hexane in the…

Distillation is a method used to purify a liquid. Distillation is a process of heating a liquid to boiling and then collecting the condensed vapors from the boiling liquid in a different vessel. After the setting up the glassware for the simple distillation I found the boiling points for each four fractions. The boiling point range for the first fraction was 29.3°C to 29.5°C. The boiling point range for the second fraction was 31.1°C to 40.6°C. The boiling point range for the third fraction was…

By using the techniques of simple distillation and gas chromatography to purify and determine relative proportions of volatile compounds in their gas form. Distillation could be described as a process where a mixture was heated until it began to boil, and the condensed vapor was collected. After completing the distillation process, the gas chromatography method could be used to identify the relative components of a compound in a volatile mixture. According to the analysis between the…

Several methods have been described in the literature for the determination of MNT in its pharmaceutical dosage forms or in biological samples. Examples of these methods in biological samples are gas chromatography – mass spectrometry (GC-MS) [18] in plasma and urine of rats and human while GC-FID [19] was used for MNT analysis in human urine. Also, MNT in mixture with other drugs have been assayed in human plasma using GC-FID [20]. In pharmaceutical preparations, MNT has been assayed using HPLC…