First of all, what is chromatography? In simplest terms, chromatography is a procedure used most frequently in the field of chemistry and physics; it refers to the process of separating certain molecules from mixtures for the purpose of analysis of these molecules, or the purification of the mixture. There are various terms associated with chromatography depending on the particular mixture to be separated, the mobile phase, and the methods used: these include column chromatography, gas chromatography, paper chromatography, affinity chromatography, journal chromatography and gel chromatography.
Yet another of these methods is liquid chromatography, which is generally used in organic substances. It works by employing a liquid mobile phase, or a solid in liquid or a liquid in solid phase. Liquid chromatography is more widely used than other methods such as gas chromatography, because samples to be analyzed wouldn't need to be vaporized; in theory any compound can effectively be subjected to this mode of analysis. Also, variations in temperature have a negligible effect in liquid chromatography (in contrast to gas chromatography).
The more effective method of liquid chromatography is known as high performance liquid chromatography, which utilizes high pressure and small packing particles in the separation process. Within this category are areas such as ion chromatography, which is able to separate ions from solutions for analysis, vacuum-liquid chromatography, and liquid chromatography-mass spectrometry, which has a high level of sensitivity through the use of electrospray ionization.
What are the most common applications of liquid chromatography? Liquid chromatography is used generally for the analysis of the components of a mixture or compound, and this attribute in itself presents a huge range of potential. For example, forensics utilizes liquid chromatography in the examination of compounds during trace analysis and toxicological analysis. Substances and mixtures commonly analyzed include explosive, dyes, drugs, alcohol and unknown substances (for identification purposes).
In food safety, food and beverages can be thoroughly analyzed with liquid chromatography to determine its components and whether they are safe for human consumption. Some of those that are analyzed liquid chromatography include fruit juices, sports drink, beer, soft drinks and wine. Harmful substances that can be detected include melamine and pesticides.
In environmental science, water could be screened by liquid chromatography for trace metal elements, explosive elements, pesticides and herbicides. In addition, liquid chromatography is also used for purification purposes. This is specially applied for the screening and treatment of municipal and industrial water supply, along with the analysis of wastewater.
In biochemistry, there have been some published studies that report to being able to efficiently and relatively easily undertake mitochondrial DNA sequencing analysis through the use of denaturing high-performance liquid chromatography. This is actually applied mostly in the field of forensic science.
There are many industrial suppliers of liquid chromatography devices available online. Some of these include waters.com, where you can browse its pages depending on the country you are in, and where you can request them to facilitate an onsite training regarding chromatography and their products; and Buchi Laboratories at buchi.com.
If you want to learn more specific information about chromatography and its applications, you can subscribe to chromatography journals from informaworld.com.