Gas Chromatography(GC) is an instrumental technique employed forensically in drug analysis, food analysis and toxicology analysis of other non chemical compounds. It is also termed as Gas-Liquid Chromatography which is used to separate complex compounds. Gas Chromatography is better when juxtaposed to paper or thin-layer chromatography. The fundamental principle of gas chromatography is that the sample solution injected into the instrument penetrates a gas stream which transports the sample into a separation tube known as the “column”. The varied components are separated inside this column. It has two major kinds
- Gas-solid chromatography
(stationary phase: solid)
- Gas-liquid chromatography
(stationary phase: immobilized liquid)
Gas Chromatography is contemplated to be a significant biophysical technique that enables the separation, identification and refinement of the components of a mixture for quantitative and qualitative analysis. The practical demands for gas chromatography include carrier gas, flow regulators and flow meters, injection devices, columns, temperature control devices, detectors, recorders and integrators. Gas chromatography has been affirmed by a good number of industries and is now used for an increasingly expanding list of applications. To date, there are a wide number of purposes of gas chromatography.
The prominent applications of Gas Chromatography are listed below:
- Food industry
Analysis of foods like carbohydrates, additives, preservatives, proteins, lipids, vitamins and amino acids is carried out by gas chromatography. It can also recognise the contaminants such as aflatoxin, a cancer-causing chemical generated by a mold on peanuts.
- Quality and Quantity analysis
It’s not just food that gas chromatography is beneficial in analysis. You may have wondered how the manufacturers of the smooth liqueur preserve their quality and quantity. The owners take their brands very sincerely and rigorously monitoring the levels of sugar that go into the final product. With no margin for error, gas chromatography is called upon to guarantee top quality and quantity in every container.
- Pharmaceutical analysis
Due to its accelerated and accurate analytical result, Gas chromatography is applied to work out the nicotine level in pharmaceutical drugs formulation. Its applications with other techniques are also essential in pharmaceutical industries for the isolation and characterization of volatile compounds. Currently, the utilization of GC in pharmaceutical quantitative chemical analysis is extremely beneficial and includes the analysis of samples of active pharmaceutical ingredients and their intermediates also as in-process examination for residual solvents to optimize the drying process.
- Forensic science
As gas chromatography is useful in distinguishing the individual elements and molecules present in a compound, it has been implemented in forensic pathology to determine which fluids and compounds are present inside a human body after death. This is vital in discovering whether or not the person was intoxicated either from alcohol or drug abuse at the time of death or indeed whether there is any poison or other destructive substance present in their body. This is imperative knowledge to ascertaining the cause of death and possible motive and culprit in the case of foul play.
- Petrochemical industry
Gas chromatography has gained large-scale applications in monitoring petroleum refining and finished product experimentation. This is evidenced by the evolution of several dedicated versions of methods based on gas chromatography. Large-scale refining operations demand fact decisions on process parameter changes delay of even a minute can result in colossal losses so these are succeeded easily using Gas chromatography. Analysis of finished commodities such as liquefied natural gas, naphtha, gasoline, aviation fuel, gas oil, lubricants, grease, wax, asphalt is carried out by GC.
- Blood alcohol analysis
One of the rapid methods for the computation of ethanol in the blood is Gas chromatography. Nitrogen is employed because of the carrier gas, n-propanol as an indoor standard and detection by flame ionization. An integrator-automatic printer system is applied to calculate and record results.
- Measuring air pollution
Air pollution has become a prominent problem in recent years. Rapid urbanization has led innumerable people to live in cities where they are exposed to the pollutants discharged by vehicles and industry. Gas chromatography is used to combat the problem, by controlling the levels of harmful pollutants in the air so that scientists can visualize where air contamination is more concentrated, and how this changes throughout the day and the year to develop efficient preventative methods.
- Real life
Gas Chromatography is utilized in airports to detect bombs. This can also take the crime scene trial (the analysis of blood or cloth samples) as an example. Arson verification (identifying the chemicals responsible for a fire to see whether there was a foul play) and blood testing after death to ascertain the levels of drugs or toxic substances in the body.