Chapter 6 - Extraction and Purification of Nucleic Acids and Proteins

Abstract

The extraction of nucleic acids and proteins is the most crucial method used in molecular diagnosis. This is because they are the key components for current high-throughput genomic and proteomic research. Nucleic acids and protein can be isolated from any biological material such as living or conserved tissues, cells, virus particles, or other samples for analytical or preparative purposes. In general, a successful nucleic acid purification requires four important steps: effective disruption of cells or tissue, denaturation of nucleoprotein complexes, inactivation of nucleases, and removal of contamination. The target nucleic acid should be free of contaminants including protein, carbohydrate, lipids, or other nucleic acids. On the other hand, the main concern in protein preparation is prevention of protein degradation. The quality and integrity of the isolated nucleic acid or protein will directly affect the results of all succeeding diagnosis. After collection of samples, whether the sources are from clinical samples, microorganisms, or soil, cell extracts are the first step for nucleic acid or protein preparation. Based on cost-effectiveness, time-efficiency, and technical instruments, the best-suited methods should be chosen based on their purpose. Here, we discuss the preparation methods for nucleic acids and protein.