A transfection reagent is a carrier for DNA that a researcher can use to insert the DNA into cells in culture. A number of types of reagents are available through life sciences companies, and researchers can also develop their own for custom applications. These molecules can work in a number of different ways to carry DNA into the target cells and insert it into their genome. The typical process involves mixing the desired DNA with the reagent, adding it to cells in culture, incubating them, and then screening them to see which contain the new DNA.
DNA transfection is a very important research tool. Researchers can insert genetic material to turn genes on or silence them and may use transfection to force cells in culture to perform in a particular way. The goal may be transient genetic expression for the purpose of study. It can also be a permanent modification that will allow the researcher to create a colony of cloned cells all expressing the same gene. These cells can be used in research and may have therapeutic applications.
Calcium phosphate is one of the oldest transfection reagents. Researchers also use lipid-based materials, which tend to be highly effective. They may also use viral DNA vectors as well as mechanical methods like microinjection, where the desired DNA is directly injected to reduce the risk of degrading the material. Gene guns are another popular tool for DNA transfection.
When a researcher selects a transfection reagent, there are a number of considerations. These include how the reagent will be used, what kind of DNA is involved, and what kind of effects the researcher wants. The transfection reagent is not always perfectly reliable, and the researcher also needs a good screening tool to find and isolate the successfully transfected cells. This will allow the researchers to discard cells that didn't accept the new genetic material along with cells that did, but express it in an unusual way that suggests some degradation of the DNA may have occurred.
DNA transfection reagent lists are available from life sciences companies. Most have a chart to help researchers decide which to use, on the basis of cell type and what kind of genetic material the researcher wants to insert. Researchers can usually request samples to allow them to test a reagent before committing to its use in research. It is important to read the documentation carefully to make sure the operation of the transfection reagent is fully understood before use.