Molecules such as DNA, RNA, proteins, and others can be moved into the target cell. The process is called transfection. It is carried out in order for those molecules to be delivered into the semi-impermeable plasma membrane of the cell. The possible applications of transfection are for therapeutic purposes (i.e. gene therapy) or for research.
Several methods are used nowadays for transfection. One of them is the gene gun. It is regarded as a biolistic particle delivery system because the nanoparticle of an inert solid (e.g. gold) carrying the target gene on its surface is fired into the target cell at very high speeds.
Gene guns are originally used for transfecting plant cells. However, Gene guns can also be used in human and animal cells. For instance, gene gun can be used to deliver DNA vaccine. It is also used in labeling subsets of cells in cultured tissue.