Agarose gel is used in the process of electrophoresis, which separates fragments of DNA according to their structure and dimensions DNA molecules are generally digested with restriction enzymes, and agarose gel electrophoresis serves as a diagnostic tool to help researchers visualize fragments. Agarose gel is a thick, viscous substance, comprised of polysaccharide matrixes, that essentially catches molecules transported by electric currents.
The technique of agarose gel electrophoresis has several important applications. This method is used in forensic science, as well as chemical labs and in pharmaceutical and medical fields. According to ASU, agarose gel enables people to analyze DNA fragments that occur as a result of enzyme digestion from larger pieces of DNA. The gel allows for clear visualization of fragments, which is essential for determining particle size in many fields of research. As DNA molecules are placed on fields with electric currents, negatively charged molecules migrate towards the positive end of the field, which contains positively-charged agarose gel. The gel is a cross-linked matrix network that serves as a three-dimensional mesh or screen to attract negatively charged DNA molecules. Those molecules are pulled to the positive end of the gel base by currents, but encounter resistance from the agarose, which then isolates DNA molecules.