Self-Assembled Hollow Nanocapsule from Amphiphatic Carboxymethyl-hexanoyl Chitosan as Drug Carrier

Abstract

A new type of amphiphilic chitosan, which was synthesized through the use of both hydrophilic carboxymethyl and hydrophobic hexanoyl substitutions, was employed to self-assemble into a hollow nanocapsule in an aqueous environment. Critical aggregation concentration (cac) and zeta potential were experimentally identified for the amphiphilic chitosan (CHC). Both experimental data suggested that the self-assembly behavior of the CHC is fundamentally determined as an interplay between the hydrophobic interaction and the variation of the zeta potential upon hexanoyl substitution, which further influenced the nanostructural evolution of the nanocapsules. Higher hexanoyl substitution promoted larger nanocapsules, ca. 200 nm in diameter, while a reduced zeta potential was correspondingly detected, and vice versa, forming smaller nanocapsules, ca. 20 nm in diameter. The selfassemble mechanism, together with the corresponding nanostructural stability, of this unique CHC nanocapsule was also proposed in terms of intermolecular interaction and thermodynamic reason. By taking the advantage of the self-assemble (or self-aggregation) capability, the CHC was employed for drug encapsulation, i.e., doxorubicin, an anticancer molecule; we found in this preliminary evaluation that it reached an efficiency of 46.8%, and a corresponding drug release from the nanocapsules for a time period exceeded 7 days can be achieved in vitro.

Photo-responsive shell cross-linked micelles based on carboxymethyl chitosan and their application in controlled release of pesticide

“…When the uncrosslinked NBS-CMCS-2 micelle solution was irradiated under UV light for 10 min, the diameter measured by DLS decreased to about 40.6 nm (see Table 1). This implies that photoremovable side NBS groups were cleaved from CMCS main chains under UV irradiation, causing a formation of single molecule aggregate (Liu, Chen, Liu, & Liu, 2008;Chen, Du, Tian, & Sun, 2005). In contrast, the cross-linked NBS-CMCS-2 micelles allowed for the formation of a stable structure after photolysis, their average diameter increased from 196 ± 0.11 nm to 238 ± 0.20 nm.…”

Design and characterization of antitumor drug paclitaxel-loaded chitosan nanoparticles by W/O emulsions

“…As the partial N-deacetylated derivative of chitin, chitosan (CS) is a natural cationic aminopolysaccharide polymer and has unique biological properties such as biocompatibility [2], biodegradability, antibacterial [3] and low toxicity, which makes it has extensive applications in drug delivery [4][5][6], tissue engineering [7] and wound repairing [8,9].…”

Self-assembled polysaccharide nanostructures for controlled-release applications

“…Liu and coworkers [38,39] prepared amphiphilic chitosan that self-assembled into hollow nanocapsules. The hydrophobic/hydrophilic balance was manipulated through functionalization of chitosan with hydrophilic carboxymethyl and hydrophobic hexanoyl moieties.…”