Polyion complex micelle

Harada A, Kataoka K. Formation of polyion complex micelles in an aqueous milieu from a pair of oppositely-charged block copolymers with poly(ethylene glycol) segments. Macromolecules 1995 28 5294-5299. 

Kataoka, K., H. Togawa, A. Hareda, K. Yasugi, T. Matsumoto, and S. Katayose. 1996. Spontaneous formation of polyion complex micelles with narrow distribution from antisense oligonucleotide and cationic block copolymer in physiological salin6/lacromolecule 9 8556-8557. 

The B block may consist of a water-soluble polymer, for example, poly(aspartic acid) P(Asp), that is rendered hydrophobic by the chemical conjugation of a hydrophobic drug (Yokoyama et al., 1992, 1993, 1996 Nakanishi et al., 2001), or is formed through the association of two oppositely changed polyions (polyion complex micelles) (Hatada etal., 1995,1998 Kataoka etal., 1996). Drugs used to couple the B block include cyclophosphamide, doxorubicin, cisplatin, pyrene, and iodine derivative of benzoic acid (Kwon and Kataoka, 1995 Trubetskoy et al., 1997 Yu etal., 1998). 

Hatada, A. and K. Kataoka. 1998. Novel polyion complex micelles entrapping enzyme molecules in the core preparation of narrowly-distributed micelles from lysozyme and poly(ethylene glycol)-poly(aspartic acid) block copolymer in aqueous mediuWiacromoleculeSI 288-294. 

Figure 9.4 Core-shell polyplex structures (A) cationic particles with a core from neutralized DNA and polycation and a corona from polycation chains adsorbed on the core (B) electroneutral particles ( polyion complex micelles or block ionomer complex ) with a core from neutralized DNA and poly cation and a corona from nonionic water soluble polymer.

Harada, A. and Kataoka, K. (1997) Formation of stable and monodispersive polyion complex micelles in aqueous medium from poly(L-lysine) and poly(ethylene glycol)-poly (aspartic acid) block copolymer. J. Macromol. Set, PureAppl. Chem., A34, 2119-2133. 

Harada, A., Togawa, H. and Kataoka, K. (2001) Physicochemical properties and nuclease resistance of antisense-oligodeoxynucleotides entrapped in the core of polyion complex micelles composed of poly(ethylene glycol)-poly (L-Lysine) block copolymers. Eur. J. Pharm. Sci., 13, 35—42. 

Vinogradov, S., Batrakova, E., Li, S. and Kabanov, A. (1999a) Polyion complex micelles with protein-modified corona for receptor-mediated delivery of oligonucleotides into cells. Bioconjug. Chem., 10, 851-860. 

Oishi et al. coupled lactosylated PEG to siRNA via an acid labile (S-thiopropio-nate bond, followed by complexation with poly(L-lysine) into polyion complex micelles. The complex was internalized by receptor-mediated endocytosis into hepatoma cells and the gene silencing effect of RNAi was considerably enhanced compared to the free conjugate, demonstrating the effect of pH-sensitive PEGylation [56]. 

Harada A, Kataoka K (2003) Switching by pulse electric field of the elevated enzymatic reaction in the core of polyion complex micelles. J Am Chem Soc 125 1530 15307. 

Har ada-Shiba M, Yamauchi K, Harada A, Takamisawa I, Shimo-kado K, Kataoka K (2002) Polyion complex micelles as vectors in gene therapy hannacokinetics and in vivo gene transfer. Gene Ther 9 407 14. 

Jaturanpinyo M, Harada A, Yuan X, Kataoka K (2004) Preparation of bionanoreactor based on core-shell structured polyion complex micelles entrapping trypsin in the core cross-linked with glutaral-dehyde. Bioconjug Chem 15 344-348. 

Zhang GD, Harada A, Nishiyama N, Jiang DL, Koyama H, Aida T, Kataoka K (2003a) Polyion complex micelles entrapping cationic dendrimer porphyrin Effective photosensitizer for photodynamic therapy of cancer. J Control Release 93 141-150. 

Recently diblock copolymers of PEG and ionic segments were prepared by atom-transfer radical polymerization of methacrylic aminoester using a monofunctionalized PEG macroinitiator and then subsequent quaternization. Like others [60] these polymers form so called polyion complex micelles by electrostatic interaction with oppositely charged molecules (e.g. drugs, oligonucleotides), where the PEG block acts as a steric stabilizer [67]. 

Figure 2 Micellar polymer assemblies from self-assembling block copolymers the polymeric micelles (a) and the polyion complex micelles (b).

Figure 5 The PIC (polyion complex) micelles from varying block polycations and DNA for delivery of genes.

Kakizawa Y, Harada A, Kataoka K. Environment-sensitive stabilization of core-shell structured polyion complex micelle by reversible cross-linking of the core through disulfide bond. J Am Chem Soc 1999 121 11247-11248. 

Kataoka K, Harada A, Wakebayashi D, Nagasaki Y. Polyion complex micelles with reactive aldehyde groups on their surface from plasmid DNA and end-functionafized charged block copolymers. Macromolecules 1999 32 6892—6894. 

Stapert HR, Nishiyama N, Kataoka K, Jiang DL, Aida T. Polyion complex micelles encapsulating light-harvesting dendrimer porphyrins. Langmuir 2000 16 8182-8188. 

R. Ideta, Y. Yanagi, Y Tamaki, F. Tasaka, A. Harada and K. Kataoka, Effective accumulation of polyion complex micelle to experimental choroidal neovascularization in rats, FEBS Lett., 557(1-3), 21-25 (2004). 

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