Deoxyribonucleic acid (DNA) is the coding material in living organisms. Complementary
pairs of nucleobases contribute to the Watson-Crick helical shape of DNA. The nucleobases are connected
through hydrogen bonding. This unique feature not only allows for genetic information to be
stored but also the assembly of complex nanostructures. DNA-based nanotechnology utilizes DNA as the
engineering materials. DNA nanodevices can be designed to work as a drug carrier with programmable
selectivity, sensor and computer. Since DNA is a natural material, the application of DNA nanodevices in
a biological environment ranging from the relatively simple cell to a complex living organism is a complex,
risky but rewarding task.