Synthesis Of Far Red/Near-Infrared Fluorescent Polymer With Aggregation-Induced Emission Characteristics And Study On Their Properties As Carriers

Reversible stabilities are required for therapeutic?e.g.DNA or medicine?delivery systems to afford adequate stability in the journey to therapeutic targets;while the systems are expected to be susceptible to structural disassembly and the liberation of their therapeutic payloads.For this purpose,we attempted to synthesize an oligoethyleneimine(OEI₆₀₀)-crosslinked polycation,characterized with self-sufficing reactive oxygen species?ROS?by virtue of a functional aggregation-induced emissive?AIE?component?with good near-infrared imaging functions?and an ROS-labile diselenide linkage.The spherical nanoparticles can be obtained by self-assembly in water by using the above-mentioned polycation?OEI-SeSex-AIE?as a carrier encapsulating pDNA or medicine.The pDNA and AIEgen were encapsulated in OEI-SeSex-AIE to constitute a gene vector AIE NPs,which could capable of exerting facile ROS production upon convenient daylight irradiation?unprecedented ROS-producing efficiency of 80.14%?,consequently helping to activate an endosomal escape functionality and the fragmentation of the OEI-crosslinked polycation into low molecular weight OEI products,and then release pDNA for further transfection process.In the other experiment,we used a OEI-SeSex-AIE carrier to encapsulate two anticancer drugs,cisplatin and a cationic biscyclometalated Ir?III?complexes,to form the nanocomplexes?SOAPIr NPs?.Under the irradiation of white light,the carrier can achieve the release of the contained drug to kill the tumor cells.Consequently,the engineered capabilities enabled the spatiotemporal control of the stabilities of the self-assembled formation so that it was adequately stable in the transportation journey to the targets but could reverse the stabilities to liberate encapsulation to execute the subsequent biological processes,evidenced by the disassociation of the near-infrared emission under corresponding wavelength.Therefore,our devised strategies provided tempting design implications for utilizing daylight as an impetus for the intracellular delivery of functional molecules,and thus could be developed further to find broad utilities in the transportation of a variety of biological substances in therapeutic applications.