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Genomic DNA extraction: an introduction

Genomic DNA is abbreviated as gDNA or called chromosomal DNA because it is packaged into chromosomes. It is the genetic code that is present in every cell and is expressed in many different combinations that lead to different cell differentiation and expression. The DNA is transcribed into RNA molecules that become proteins with many different functions. Many laboratories around the world perform genomic DNA extractions. The purpose of the genomic DNA extraction is to separate the genomic DNA from the rest of the cell contents to study it. Genomic DNA is studied by those interested in learning about specific genes and learning from genomic sequencing.

The sandwich ELISA is a type of Enzyme-linked immunosorbent Assay that uses two antibodies: a capture antibody and a detection antibody. It is called a sandwich because your antigen is bound between antibodies. The purpose of any ELISA is to detect the presence of a target antigen in a sample. In a sandwich ELISA the target antigen is bound between a capture antibody and a detection antibody. The capture antibody is immobilized on a surface, while the detection antibody (conjugated to an enzyme or fluorophore label) is applied as a last step before quantitation.

Nucleic acids refer to biomolecules composed of nucleotides. A nucleotide is the name of a nucleic acid monomer which consists of a 5-carbon sugar base bound to a nitrogenous base and a phosphate group. The type of nucleotide is based on the type of nitrogenous base that is bound. For deoxyribonucleic acid (DNA) the four predominantly found bases are guanine, adenine, cytosine, and thymine. For ribonucleic acids (RNA) the four main bases are guanine, cytosine, thymine and uracil. Both DNA and RNA are part of the central dogma of molecular biology and are studied extensively.  Nucleic acids are also used for research and therapeutic purposes. In order to study and use nucleic acids, it is important to have a system of nucleic acid labeling. Nucleic acid labeling can also be used to track nucleic acids.

Importance and uses of cell isolation

There are many different types of cells, there are 200 types of cells in the human body alone. To give an example overview of the types of cells, there are red blood cells, white blood cells, muscle cells, bone cells, nerve cells and many more. In order to study all the individual cell types, scientists use cell isolation to get specific cells alone to study them. There are many reasons to study a cell, from the internal to external mechanisms. For example, some researchers study the motility of cells. They explore how the cells move and how the cytoskeleton plays a role in those movements. Experiments can also be done that give the cells certain molecules and the effects of those molecules on motility can be observed. Scientists are also interested in studying how cells divide and study if certain gene mutations cause differences in how cells divide. For those interested in clinical reasons for cell isolation, it is important to do cell isolation for blood to separate the components into useful therapeutic components.

The ability to isolate cells is important in both clinical and research settings. The goal of cell separation is to isolate one population of cells that are of interest. There are several reasons for performing cell separation, some examples are interest in studying a cell type or using it for therapy such as T-cell therapy. Some researchers are interested in cell separation to be used for creating hybridoma cell lines or for testing drugs in vitro and seeing the effect of the drugs on cells. There are many available techniques for cell separation. These techniques differ in specificity of cell selection, cost of equipment, time to complete, technology needed, and skill required. Cell separation based on cell density is rapid and inexpensive, but is unspecific. Still, it is a fundamental technique that is commonly used in a variety of settings for general cell separation.

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. 

The capability of 1 μm and 2.8 μm magnetic particles to intracellularly deliver cargo proteins

In a recently published paper, researchers of the CIBER-BBN and the University Autonoma de Barcelona demonstrated that magnetic microparticles of 1 and 2.8 μm of diameter, in combination with an appropriate magnetic force, could greatly decrease the time needed to interact with and enter target cells, a clear advantage over other types of drug delivery systems.

Enzymes: an overview

Enzymes are proteins with the ability to catalyze chemical reactions. We have several articles you can read to learn more about proteins, their uses, and isolating them for research and clinical purposes. Check out our protein isolation article if you are thinking about how to best purify your protein of interest or read our protein assay article to learn more about working with proteins. Enzymes are particularly interesting and useful due to their catalytic activity. The molecule that goes into the enzyme for manipulation is called the substrate. You will often see this interaction called the “lock and key” interaction as the substrate has to fit just right into the pocket of the enzyme for it to work properly (enzymes are highly specific!), the way a key is very specific to the lock it goes into.