Fig. 3.

The main types of phages used as nanocarriers in drug and gene delivery. A M13 phage is approximately 880 nm in length and 6-7 nm in diameter. It is mainly composed of five capsid proteins (pIII, pVI, pVII, pVIII, pIX) and encapsulated cssDNA. B T7 phage has an icosahedral head of 55 nm in diameter, which encapsulates a 40 kbp linear dsDNA, and the tail is 19 nm long, short and uncontracted. C T4 phage has an icosahedral head with a length of 120 nm and a width of 86 nm, which encapsulates a 171kbp linear dsDNA, and six tail fibers with a length of 160 nm are attached to the tail. The tail is long and retractable. D Lambda phage has an icosahedral head with a radius of approximately 30 nm, which encapsulates a linear 48.5 kbp dsDNA, and a tail with a length of 150 nm. E MS2 phage consists of a ssRNA and 180 protein subunits surrounding its genome to form an icosahedral capsid about 27 nm in diameter