Passive and Active Targeting

L. Ilium and S. S. Davis, Passive and active targeting using colloidal carrier systems, in Drug Targeting (P. Buri and A. Gumma, eds.), Elsevier Science Publishers, Amsterdam, 1985, p. 65. 

Cancer Therapy Nanoparticles were first prepared with the concept of targeting colloidal carriers of nanosize to tumor tissues via the leaky vasculature in tumor regions. Since then nanoparticulate drug carriers have been associated with cancer therapy through passive and active targeting to cancer cells. Thus, amphiphilic CD nanoparticles were mainly focused on cancer therapy and its different aspects. 

Fig. 1 Schematic illustration of passive and active targeting mechanisms.

Fig. 1 Structures of dendritic nanomaterials. (a) Dendrimers have a well-defined hierarchical structure consisting of a core, branch, and periphery, (b) Each generation is added to the structure by repeating the reaction sequence of stepwise synthesis, which generates two new branching points, (c) Dendrimers can be encapsulated into relatively large nanoparticles such as liposomes and polymeric nanoparticles (50-200 nm in diameter), which can aim both passive and active targeting strategies.

Targeting is often defined in terms of passive and active targeting where passive has come to refer to the accumulation of drug due to physicochemical or pharmacological factors naturally occurring in the body. Active targeting is due to a (more or less) specific interaction between delivery system and cell or tissue component (Garnett 2001). 

Figure 2.1. The schematic representation of the passive and active targeting of nanoparticles in cancer.

Third, passive and active targeting can be achieved by taking advantage of nanoassemblies properties. As discussed above, nanoassemblies hardly go through the tight blood vessels into the extracellular space from the blood and have slow renal clearance due to their large sizes. In contrast, the vasculature in tumor tissues is known to... 

We hope MCC-465 will be the state of the Art for the treatment of patients with advaneed gastrie eaneer, because it may be able to kill the gastric cancer cells effectively through passive and active targeting. 

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