An oral drug delivery system with programmed drug release and imaging properties for orthotopic colon cancer therapy

• DOI: 10.1039/c9nr03802g
• Publication Date: 2019-08-06T20:22:14Z
• Authors: Qingling Song; Jiajia Jia; Xiuxiu Niu; Cuixia Zheng; Hongjuan Zhao; Lingling Sun; Hongling Zhang; Lei Wang; Zhenzhong Zhang; Yun Zhang
• Keywords: Targeted drug delivery

Oral drug delivery systems (ODDSs) have attracted considerable attention in relation to orthotopic colon cancer therapy due certain popular advantages. Unfortunately, their clinical applications are generally limited by the side-effects caused systemic exposure and poor real-time monitoring capabilities. Inspired characteristics of pH changes gastrointestinal tract (GIT) specific enzymes secreted colonic microflora, we anchored polyacrylic acid (PAA) chitosan (CS) on Gd3+-doped mesoporous hydroxyapatite nanoparticles (Gd-MHAp NPs) realize programmed release magnetic resonance imaging (MRI) at tumor sites. In particular, grafted PAA, as a pH-responsive switch, could effect controlled colon. Further, CS is functionalized enzyme-sensitive moiety, which be degraded β-glycosidase Gadolinium paramagnetic lanthanide element used chelates, working contrast medium agent for an MRI system. Interestingly, after oral administration, PAA protect drug-loaded (NPs) against variable physiological conditions GIT, allowing reach sites, preventing premature release. Enhanced concentrations sites were achieved via this release, subsequently ameliorated therapeutic effect. addition, encapsulating both chemotherapeutic (5-fluorouracil, 5-FU) targeted (gefitinib, Gef) within Gd-MHAp NPs produced synergistic summary, study demonstrated that such novel system (Gd-MHAp/5-FU/Gef/CS/PAA protect, transport, program locally environment; further, exhibited worthwhile effect, providing promising treatment strategy cancer.