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Magnetic DNA purification is a simple and reliable way to isolate DNA. 

Nucleic acid (DNA and RNA) isolation and amplification is an important tool for molecular biology and important step before many biochemical and diagnostic processes. These techniques have made great progress recently [1][2] due to the increasing number of sudden and public health-threatening infectious diseases (e.g. Ebola virus, Zika virus and more recently SARS-Covid) prompting the wide applications of nucleic acid detection for the on-site immunological technologies and rapid kits (for magnetic mRNA purification refer to “Oligo dT-coated magnetic beads: the benefits of their application for mRNA purification”).

Good manufacturing practice, or GMP, is a set of standards that ensures that produced products meet a set of quality standards. Following GMP is crucial for the production of laboratory equipment, as it ensures that a manufactured product is able to meet predefined criteria. Most GMP practices follow the guidelines set by the FDA in the United States, and are promoted by the WHO.

Overview of cell biology and its importance

The main two categories of cells are prokaryotic and eukaryotic cells. Prokaryotic cells are what make up bacteria and archaea while eukaryotic cells make up organisms of the domain eukaryota. The inside of the prokaryotic cell houses it’s genetic material, DNA, in a region called the nucleoid region. There are also ribosomes within the central region of the bacteria. The next layer is the plasma membrane, a bi-lipid layer like you will see for eukaryotic cells. Unlike eukaryotic cells, prokaryotic cells will have a cell wall and a capsule surrounding the cell membrane. The eukaryotic cell is surrounded by a lipid membrane, and has membrane-bound organelles. The genetic material, DNA, is stored in the nucleus which is a membrane bound organelle. In research, many different types of cells are used. Bacterial cells are used in protein purification to grow a plasmid to express a protein of interest. You can read about this in our article protein expression and purification. Many types of Eukaryotic cells are used to do in vivo studies. Depending on your research interests, you might use muscle cells, or skin cells, or cancer cells. 

Cell based assays are used to quantify cellular function, measure how stimuli affect cells, or to localize an effect within the cell. The cells are live and intact, and require the use of fluorescent tags and chemiluminescent or colorimetric enzymes. The quantification is performed by flow cytometry or microscopy. This is very different from studies of protein or nucleic acid which require destruction of the cell and isolation of those components from cell lysate. A cell based assay is conducted entirely within live, intact cells. The goal is to understand a cellular process, localization of a molecule or drug to a cellular compartment, or to measure how cells react to a substance. Cell based assays are usually performed in tightly controlled cell lines to test for a wide range of behaviors: