Chemosensitizing indomethacin-conjugated chitosan oligosaccharide nanoparticles for tumor-targeted drug delivery

摘要

A chitosan oligosaccharide (CSO)-indomethacin (IDM) conjugate (CI) was synthesized to fabricate chemosensitizing nanoparticles (NPs) for tumor-targeted drug delivery. IDM was conjugated to a CSO backbone via amide bond formation, of which successful synthesis was confirmed by proton-nuclear magnetic resonance analyses. Doxorubicin (DOX)-loaded CI (CI10/DOX; CI:DOX = 10:1 [w/w]) NPs with <75 nm of mean diameter, polydispersity index of similar to 0.2, and positive zeta potential were prepared. The release of DOX from the NPs was enhanced at acidic pH (pH 5.5 and 6.8) compared to physiological pH (pH 7.4). The release of IDM increased in the presence of A549 cell lysates. In A549 cells (human lung carcinoma cells), more efficient cellular uptake of CI10/DOX NPs than that of free DOX was observed by using confocal laser scanning microscopy and flow cytometry. The in vitro cytotoxicity of CI10/DOX NPs in A549 cells was higher than those of free DOX and CI NPs with free DOX groups. In vivo pharmacokinetic studies after intravenous administration in rats showed significantly lower clearance of DOX from NPs compared with the free DOX group. Tumor targetability of the developed CI NPs was also verified by a real-time optical imaging study. In summary, the chemosensitizing CI/DOX NP with enhanced anticancer activity, prolonged blood circulation, and passive tumor targeting can be a promising anticancer drug delivery system for tumor-targeted therapy.