| In recent years, some researches on cancer treatment have been going on and nano drug carriers have been received tremendous attention for its inherent advantages. Among the redox-responsive nano-drug delivery systems (DDS), disulfide bond is of great interest because of its instability under the reducing glutathione (GSH). The redox-responsive nano-DDS not only tend to have increased accumulation in tumors by the passive targeting, but also release drug relative with the different GSH concentrations in cell.Great achievements based on molecularly imprinted polymer (MIPs) have been made in many fields, such as purification and separation, and chiral recognition, due to the physical robustness, thermal stability, as well as easy preparation of the MIPs. Few researches have been done in nano-drug delivery systems through MIPs up to now.In this study, we synthesized redox-responsive nano-DDS with doxorubicin (DOX) as template for the treatment and imaging of cancer cells by MIPs technique using different functional monomers and crosslinkers. The details are shown as followings.1. GSH-responsive degradable MIPs were synthesized on the nano silica surface, with (3-Aminopropyl)trimethoxysilane and ethylsilicate(TEOS) as functional monomer and crosslinker. The composition, morphology and properties of the makings have been characterized by 1HNMR, FTIR, TGA and TEM. The low cytotoxicity of the materials demonstrated its excellent biocompatibility. Meanwhile, the degradation study of makings showed that the materials would break into hollow particles after interacting with GSH. The release of DOX followed by the decomposition of makings within cancer cells was further confirmed by flow cytometry and confocal laser scanning microscopy studies.2. Smart nano drug carriers of MSNs@DOX@MIP were synthesized by MIPs with mesoporous silica (MSNs) as the adsorbent for DOX. The composition, morphology, and properties of the as-prepared composites were characterized by elemental analysis, fluorescence spectroscopy, FTIR, UV-visible spectroscopy, TEM, HRTEM, nitrogen adsorption-desorption, TGA and DLS. In vitro release experiments showed that under simulated conditions of endosome with pH 5.0 and GSH 10 mM, the release of DOX were promoted from mesoporous to the external environment.While under blood environment, since the mesoporous had been closed through polymer on the surface, DOX were hindered to release. The adsorption studies also indicated that DOX@MSNs@MIP had sustained release ratio of DOX and had high growth inhibition toward cancer cells. |
