Chromatography
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DESCRIPTION:
Simply put, chromatography is the process of separating compounds and individually identifying them by certain colors. The “stationary phase” is first used and allows the “mobile phase” to pass through the “stationary phase” therefore acquiring some of the tested compounds as it moves. As the “mobile phase” makes its way through the testing plane, more and more of the tested compound are becoming absorbed. By looking at how far the “mobile phase” moves on the given plane the results can be calculated to indicate what the substance is. There are four types of chromatography; paper, thin layer, liquid and gas.

Moreover, chromatography has become one of the most widespread techniques used in analytical chemistry today.This can be attributed to the fact that the chromatography can take very small quantities of material and separate that material so it can then be processed and analysed. This allows chemists to breakdown complex materials and compounds with great precision. Another reason why chromatography is beneficial is that it, "can be used to separate delicate products since the conditions under which it is performed are not typically severe." Chromatography is used to in the healthcare sector to make sure that the various drugs are synthesized from the reactants.



APPLICATIONS:
Chromatography is commonly used in chemistry to analyze different compounds, and is most commonly known for sequencing DNA. The fact that this process is centered around color coding also makes it incredibly valuable to organizations such as the FBI or CIA when coming into contact with an unknown substance, such as bombs within airports or fibers found than need to be analyzed. It is also commonly used to detect cocaine in urine, alcohol within the blood stream, PCB’s in a fish population and lead in drinking water.


TYPES:paper.png
Paper Chromatography: Simple method for testing a sample biased on the polarity of the molecules in the sample. A dot or line of the sample solution is put on a strip of chromatography paper and placed in a solvent biased on the type of sample. As the solvent is wicked up the paper, it comes in contact with the sample which travels up the paper with the solvent, and is deposited at different intervals biased on the polarity of the molecules.





High-Performance Liquid Chromatography(HPLC): This is used to separate mixtures or find relevant amounts in a compound mixture. HPLC is most often seen and used in biochemistry and analytical chemistry. There are many parallels between HPLC and paper chromatography. They both go through a mobile phase (liquid) and a stationary phase (solid). High-performance liquid chromatography is very versatile; it can be used with just about any sample. This is why HPLC has become one of the most powerful tools in analytical chemistry and biochemistry. Below is a video demonstrating how HPLC is used:




WEB RESOURCES:
http://www.wisegeek.com/what-is-chromatography.htm
http://www.yesmag.ca/projects/paper_chroma.html
http://www.files.chem.vt.edu/chem-ed/sep/chromato.html
http://www.waters.com/waters/nav.htm?cid=10048919&locale=en_US
http://www.rpi.edu/dept/chem-eng/Biotech-Environ/CHROMO/chromintro.html