What transfection methods are commonly used in biology?

Transfection is the process of deliberately introducing naked or purified nucleic acids into eukaryotic cells by non-viral methods. It can be achieved by physical or chemical techniques. Examples of physical methods are electroporation, microinjection, cell squeezing, sonoporation, as well as gene gun. Chemical based transfection include the cheap ones using reagents like calcium phosphate and organic dendrimers, and more advanced ones such as lipofection and Fugene technologies.