Chitosan hydrophobically modified

Thongborisute J, Takeuchi H, Yamamoto H, Kawashima Y (2006a) Visualization of the penetrative and mucoadhesive properties of chitosan and chitosan-coated liposomes through the rat intestine. J Liposome Res 16(2) 127-141 Thongborisute J, Takeuchi H, Yamamoto H, Kawashima Y (2006b) Properties of liposomes coated with hydrophobically modified chitosan in oral liposomal drug dehvery. Pharmazie 61 (2) 106—111... 

Hydrophobically modified polymers can associate in aqueous media to form micelle-like structures above their critical association concentrations (CACs). The nanosized self-aggregates were prepared using modified natural polysaccharides such as pullulan, curdlan, and glycol chitosan. The modified polysaccharides provide excellent biocompatibility, biodegradability, low immunogenicity, and biological activities. 

Four major groups of hydrophobically modified chitosan have been used as potential drug delivery carrier for poorly soluble drugs (1) steroid derivatives, (2) fatty acids derivatives, (3) aryl and alkyl derivatives, and (4) carboxymethyl derivatives of chitosan (Figs. 3-6). Others types of modified chitosan have also been synthesized [117-119]... 

The main steroids used to hydrophobically modify chitosan are 5p-cholanic acid [72, 120], cholic acid [121], and cholesterol [76, 122] (Fig. 5). 

Hydrophobically modified glycol chitosan (HGC) with 5p cholanic acid has been extensively studied both in vitro and in vivo. This polymer was developed as a new Cremophor EL-free alternative carrier systems for docetaxel [74] and paclitaxel. Physical characteristics of the nanoparticules such as size, hydrophobic core, and stability depend on the degree of 5-p cholanic acid substitution. The maximum loading content of paclitaxel into HGC nanoparticles was 10 wt% and the loading efficiency was above 90% [120]. Cytotoxicity studies on MCF7 breast cancer cells showed that HGC nanoparticles were less toxic than Cremophor EL, and allowed a higher dose of paclitaxel administration. The survival rate of mice that received 50 mg/kg paclitaxel in HGC nanoparticles increased substantially compared to 20 mg/kg PTX in Cremophor EL-ethanol solutions [120]. 

Ortona O, D Errico G et al (2008) The aggregative behavior of hydrophobically modified chitosans with high substitution degree in aqueous solution. Carbohydr Polym 74 16-22... 

Hwang HY, Kim IS et al (2008) Tumor targetability and antitumor effect of docetaxel-loaded hydrophobically modified glycol chitosan nanoparticles. J Control Release 128 23-31... 

Park Y, Hong HY et al (2008) A new atherosclerotic lesion probe based on hydrophobically modified chitosan nanoparticles functionalized by the atherosclerotic plaque targeted peptides. J Control Release 128 217-223... 

Kim J-H, Kim Y-S et al (2006) Hydrophobically modified glycol chitosan nanoparticles as carriers for paclitaxel. J Control Release 111 228-234... 

Recently, new basal insulin formulation was designed by Jo et al. (2008). Zinc-crystallized insulin was physically loaded into hydrophobically modified glycol chitosan (HGC) nanoparticles by dialysis method (Figure 22.2). The biological activities of insulin-HGC formulations were investigated... 

Yoo, H. S., Lee, J. E., Chung, H., Kwon, I. C., and Jeong, S. Y. 2005. Self-assembled nanoparticles containing hydrophobically modified glycol chitosan for gene dehvery. Journal of Controlled Release 103 235-243. 

Ahabadi, H. M. and Lavasanifar, A. 2006. Polymeric micelles for drag deBvety. Expert Opiru Dmg Deliv. 3 139-162. Bhattarai, S. R., Remant Bahadur, K. C., Aryal, S. et al. 2008. Hydrophobically modified chitosan/gold nano-particles for DNA delivery. J. Nanopart. Res. 10 151—162. 

Xiao, E, Liu, L., Li, J., Zeng, J., and Zeng, B. (2008) Electrocatalytic oxidation and voltammetric determination of nitrite on hydrophobic ionic liquid-carbon nanotube-chitosan composite modified electrode. Electroanalysis, 20 (18), 2047 - 2054. 

Zhang J, Chen XG, Li YY et al (2007) Self-assembled nanoparticles based on hydrophobically modified chitosan as carriers for doxorubicin. Nanomedicine 3 258-265... 

Self-assembled nanoparticles containing hydrophobically modified glycol chitosan For gene delivery [139]... 

Self-assembled nanoparticles based on hydrophobically modified chitosan as Carriers for doxorubicin [141]... 

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