Enzyme-responsive strategy as a prospective cue to construct intelligent biomaterials for disease diagnosis and therapy

Stimuli-responsive materials have been widely studied and applied in biomedical field. Under the stimulation of enzymes, the enzyme-responsive materials (ERMs) can be triggered to change their structures, properties and functions....

Bioresponsive nanomedicines based on dynamic covalent bonds

Trends in the development of modern medicine necessitate the efficient delivery of therapeutics to achieve the desired treatment outcomes through precise spatiotemporal accumulation of therapeutics at the disease site. Bioresponsive nanomedicine is a promising platform for this purpose. Dynamic covalent bonds (DCBs) have attracted much attention in studies of the fabrication of bioresponsive nanomedicines with an abundance of combinations of therapeutic modules and carrier function units. DCB-based nanomedicines could be designed to maintain biological friendly synthesis and site-specific release for optimal therapeutic effects, allowing the complex to retain an integrated structure before accumulating at the disease site, but disassembling into individual active components without compromising function in the targeted organs or tissues. In this review, we focus on responsive nanomedicines containing dynamic chemical bonds that can be cleaved by various specific stimuli, enabling achievement of targeted drug release for optimal therapy in various diseases.

Multi-Responsive Bottlebrush-Like Unimolecules Self-Assembled Nano-Riceball for Synergistic Sono-Chemotherapy

Improved drug loading content, bioavailability, and controlled release in targeted tissue have been major bottlenecks in the design of precision nanomedicine. Herein, a tumor-specific and multiple-stimuli responsive nano-riceball is proposed and validated for enhanced sono-chemotherapy. The nano-riceball (NGR@DDP) possesses a well-designed core-shell structure, formed by an inner core assembly that contains ultrasound/H₂ O₂ responsive bottlebrush-like unimolecular dextran-POEGMA₉ -b-PMTEMA₂₂ (DOS) with co-loaded doxorubicin and Purpurin 18. This inner core of NGR@DDP is further buried by a "striffen" of NGR (Asn-Gly-Arg)-modified RBC-membrane derived from CRISPR-engineered mice. As a result, nano-riceball NGR@DDP is featured with high drug stuffing content (30.3 wt%), low critical micelle concentration (5.93 µg mL^-1 ), and intelligent exogenous ultrasound/endogenous H₂ O₂ stimuli-triggered precise drug release at tumor site. Under fluorescence/photoacoustic imaging guidance, combined sonodynamic therapy and chemotherapy exhibit excellent synergistic effect, and dramatically inhibit the growth of orthotopic HepG2 hepatocellular carcinoma with negligible side effects. This nano-riceball strategy provides a facile way to achieve function hybridization for personalized nanomedicine.