ナノテクノロジーとＤＤＳ デンドリマーのＤＤＳへの応用 ナノテクノロジーに基づくキャリア設計の観点から

Abstract

Dendrimers are unique macromolecules with highly branched structure and globular shape. Molecular size, structure, and properties of dendrimers are highly controllable. These characteristics of dendrimers are very useful for the precise design of drug carriers and hence their application to drug delivery has been actively attempted. A brief description of dendrimers is given and present status of dendrimer-based design of drug carriers is viewed. While some of widely used dendrimers are shown to be toxic, biodegradable and biocompatible dendrimers have also been developed. Various kinds of dendrimer-drug conjugates have been prepared using polyamidoamine, polyphenylether, and polyester dendrimers and anticancer drugs such as doxorubicin, methotrexate, and 5-fluorouracil. While some of these conjugates exhibit toxicity against cancer cells, their activity is still to be improved. Dendrimers with hydrophobic core and hydrophilic shell have been designed as unimolecular micelles. These dendrimers are able to encapsulate hydrophobic drugs in their interior and release them slowly. Dendrimers with an interior of basic environment have ability to encapsulate acidic drugs, such as inethotrexate. Surface modification of dendrimers has also been attempted. Various kinds of ligands, such as sugars and folate residues, have been attached to dendrimers. These dendrimers may be useful as drug carriers with target cell specificity. In addition, surface modification of dendrimers with poly (ethylene glycol) has been tried to obtain dendrimers with biocompatible surface. Rationally and precisely designed, dendrimer-based carriers may realize an accurate delivery of drugs to the target site and lead to an enhanced efficacy of drugs.