Gel Electrophoresis Research Paper

Forensic chemistry is the application of chemistry to provide information for use in courts of law or in public discussion and debate. It is a special branch of chemistry that is concerned with identifying the substances present in samples. A forensic chemist analyses predominantly biological samples such as blood, saliva, and semen (of which all contain DNA, proteins and amino acids) that are brought in from the crime scenes and reaches a conclusion based on tests run on that piece of evidence. One instrumental method capable of analyzing such samples is Gel Electrophoresis (GE).
Overview of Gel Electrophoresis:

Gel electrophoresis is an effective and widely used method that separates and identifies molecules on the basis of electrical charge and size. GE is a particularly useful method for separating amino acids, which are charged, organic molecules such as DNA (deoxyribonucleic acids), RNA (ribonucleic acids), and proteins. …show more content…
(Clark, HIGH PERFORMANCE LIQUID CHROMATOGRAPHY - HPLC, 2007). Samples are loaded into an agarose gel slab, which is placed into a chamber filled with a conductive buffer solution. A direct current is passed between wire electrodes at each end of the chamber. Since most molecules have a net charge, they will be drawn toward either the positive pole (anode) or the negative pole (cathode) when placed in an electric field. The matrix of the agarose gel acts as a molecular sieve through which smaller molecules can move more easily than larger ones. After a while, the molecules are separated by size. If the molecules fall into only a few discreet sizes, then bands (little rectangles) will appear in the gel. Each of these bands contains strands of a specific size. These bands can be colored with a radioactive dye to make them visible to imaging techniques. (Agarose Gel Electrophoresis of DNA,