Abstract: The present invention relates to a nanocomplex, and a pharmaceutical composition, a drug delivery system and a drug delivery method using the same. The present nanocomplex consists of a nucleic acid molecule, a monocationic drug and a biocompatible polymer surfactant, and not only has a hydrodynamic size of 10 nm or less, but uniformly distributes as a colloidal form in an aqueous environment. In addition, the nanoscale colloidal formulation of the present invention could protect the nucleic acid molecule from a nuclease (for example, serum nucleases) rich in a physiological environment through the formulation of a stable monocomplex, and provide improvement of cell penetration and in vivo delivery via a micellar structure as well as further protection of the nucleic acid molecule by a micellar passivation.

Abstract: The present invention relates to a methylene blue nanoparticle for bioimaging and photodynamic therapy, and a use thereof as a cancer therapeutic agent and a contrast agent. The methylene blue nanoparticle of the present invention for use as a topical cancer targeting photo therapeutic agent is composed of only a material of which the composition is clinically used or derived from human bodies, and thus a nanopreparation in which a barrier to clinical entry is low and the possibility of commercialization is very high, exhibits near-infrared fluorescence along with cancer targeting property, capacity of generating singlet oxygen and the like, and thus may be used for both bioimaging diagnosis such as optical imaging, and cancer targeting photodynamic therapy.