The Importance Of Chromatography In Forensics

What is chromatography along with how is chromatography used in Forensics? Well in this research paper I will be answering these questions, while explaining how chromatography has been used to solve cases not only in Georgia, but throughout the United States. First, I will start by explaining that chromatography is the separation of a mixture by passing it in a solution or suspension or as a vapor (as in gas chromatography) through a medium in which the components move at different rates. There is a science to chromatography because it separates these organic molecules using their molecular properties: molecular weight, size, or differences in molecular scaffolding (structure), but originally, chromatography separated chemical compounds by

An organic solvent or a mixture of solvents (the eluent) flows down through the column. Components of the sample separate from each other by partitioning between the stationary packing material (silica or alumina) and the mobile eluent. Molecules with different polarity partition to different extents, and therefore move through the column at different rates. The eluent is collected in fractions. Fractions are typically analyzed by thin-layer chromatography to see if separation of the components was successful. Column Chromatography is the preparative application of chromatography, which is mainly used to obtain pure chemical compounds from a mixture of compounds on a scale from micrograms to kilograms using large industrial columns. Paper Chromatography is an analytical technique for separating and naming mixtures that are or can be colored, especially pigments. This process can be used in secondary or primary schools in ink experiments, but this method has been largely replaced by thin layer chromatography; however, it is still a powerful teaching tool. Two-way paper chromatography, also called two-dimensional chromatography, involves using two solvents and rotating the paper 90⁰ in between. This method is useful for separating complex mixtures of similar compounds, for example, amino

The instrument used to perform gas chromato¬graphic separations is called a gas chromatograph (also: aerograph, gas separator). A gas chromatograph is a chemical analysis instrument for separating chemicals in a complex sample. A gas chromatograph uses a flow-through narrow tube known as the column, through which differ¬ent chemical constituents of a sam¬ple pass in a gas stream (carrier gas, mobile phase) at different rates depending on their vari¬ous chemical and physical properties and their inter¬action with a specific column filling, called the station¬ary phase. As the chemicals exit the end of the col¬umn, they are detected and found electronically. The function of the stationary phase in the column is to separate different components, causing each one to exit the column at a different time (retention time). Other parameters that can be used to alter the order or time of retention are the carrier gas flow rate, and the temperature. In a GC analysis, a known volume of gaseous or liquid analyte is injected into the “entrance” (head) of the column, usually using a micro syringe (or, solid phase micro-extraction fibers,