Most existing bioadhesives, even those showing superiority in wound closure effectiveness, do not assist in the post-wound closure process. A bioinspired, in situ formed, double-dynamic-bond crosslinked hydrogel bioadhesive that is capable of efficiently closing open wounds and enabling post-wound closure care is reported. Catechol-modified ε-poly-l-lysine and oxidized dextran are employed as natural polymer backbones and they are in situ crosslinked using Schiff 's base dynamic bond and catecholFe coordinate dynamic bond through a process inspired by that used to cure marine mussel glue, forming a hydrogel bioadhesive. The unique double-dynamic-bond crosslinked structure endows the bioadhesive with higher mechanical and adhesive strength while retaining quick dissociation and good self-healing capacities. Accordingly, the bioadhesive can exhibit multiple desirable functions, such as dissolution on demand, repeatable adhesiveness, adhesive and mechanical strength sufficient for wound closure, injectability, and good biocompatibility (DREAMING). After efficiently closing skin incisions, the bioadhesive can be facilely removed or repeatedly close the reopened wounds, thus enabling post-wound closure care. On the basis of favorable functions in wound closure and the ability to enable post-wound closure care, the bioadhesive demonstrates great potential in dealing with skin wounds.
Exosomes derived from non‐tumor cells hold great potential as drug delivery vehicles because of their good biosafety and natural transference of bioactive cargo between cells. However, compared to tumor‐derived exosomes, efficient delivery is limited by their weak interactions with tumor cells. It is essential to engineer exosomes that improve tumor cellular internalization efficiency. A simple and effective strategy to enhance tumor cell uptake by engineering the exosome membrane lipids can be established by drawing on the role of lipids in tumor exosomes interacting with tumor cells. Amphiphilic phosphatidylcholine (PC) molecules are inserted into the membrane lipid layer of reticulocyte‐derived exosomes (Exos) by simple incubation to construct PC‐engineered exosomes (PC‐Exos). It is demonstrated that PC‐Exos showed significantly enhanced tumor cell internalization and uptake rate compared to native Exos, up to a twofold increase. After therapeutic agent loading, PC‐Exos remarkably promotes intracellular drug or RNA accumulation in cancer cells, thus showing enhanced in vitro anti‐tumor activity. This work demonstrates the crucial role of engineering exosomal lipids in modulating cancer cellular uptake, which may shed light on the design of high‐efficiency exosome‐based drug delivery carriers.
Precise delivery of extracellularly functional protein drugs is limited by the drawback in that the protective carrier often causes undesirable cellular uptake of these therapeutic agents. Here, the design of a weakly cell-interacted, nanosized, environment-responsive vehicle (WINNER) with rational phosphorylcholine (PC) surface filling ratios capable of precise extracellular delivery of therapeutic agents for enhanced tumor suppression is reported. Highly hydrophilic zwitterionic PC and enzyme-responsive peptides are engineered into the functional shell of WINNER which reasonably covers the inner protein. It is demonstrated that rationally controlled PC surface filling ratios (50.5-58.3%) are necessary for weakening interactions between the cell and WINNER whilst providing enough sites on WINNER for enzyme recognition. Consequently, WINNER (50.5-58.3%) can protect inner cargos from cellular uptake and undergo enzymatic degradation, resulting in precise extracellular release of inner protein, such as therapeutic monoclonal antibody (mAb). After intravenous administration, therapeutic mAb nimotuzumab-loaded WINNER (51.2%) shows highest in vivo antitumor activity compared with free nimotuzumab or nimotuzumab-loaded PC-free nanocarrier in a lung adenocarcinoma xenograft tumor animal model. This work presents a simple and flexible approach to design precise extracellular delivery platform which can uncage the therapeutic power of extracellular targeting therapeutic agents.
Mussel‐inspired, coordinate‐crosslinked gels have attracted extensive attention but their adhesive behaviors are still not fully understood. Herein, four mussel‐inspired molecules with different molecular characteristics are synthesized to study their adhesive behaviors. It is demonstrated that their adhesive behaviors are dependent on the environments. For these mussel‐inspired molecules, physiological environment containing relatively low Fe3+ contents is appropriate for achieving high adhesive strength. In addition, the mussel‐inspired molecules with positive charge, high molecular weight, or high catechol substitute ratio benefited for improving adhesive strength, however, only in the appropriate environment. In the inappropriate environments (physiological pH, high Fe3+ contents), the adhesives show similar low adhesive strength. These environment‐dependent adhesive behaviors are due to the poor interfacial adhesive capacity of the adhesives formed in the inappropriate environments. The study uncovers the adhesive behaviors of mussel‐inspired coordinate‐crosslinked gels and thus may further provide valuable evidences in the design of metal‐crosslinked bioadhesives.
An efficient sorbitol‐based phase‐selective organogelator has been synthesized by an one‐step reaction between sorbitol and benzaldehyde with high yields up to 90%. The organogelator could gelate a wide range of oils with minimum gelation concentration ranging from 0.04 to 0.10 g/mL within 17 min. Besides, the self‐assembly mode of the organogelator in the oil phase was presented. The organogelator could self‐assemble in the oil phase through the hydrogen bonding and the π–π stacking interactions to form three‐dimensional networks. The organogelator showed better gelation properties when treated crude oil than other oils. Namely, a lower gelation concentration and a shorter gelling time were observed, while higher thermal stability and mechanical strength of the final crude oil gel were obtained. More importantly, the organogelator could be directly applied in a powder form to selectively gelate crude oil from oil–water mixtures within 10 min at ambient temperature without heating or adding carrier solvents. Inexpensive, simple‐synthesis, high‐yield and relatively simple operation performances of the organogelators indicate their potential and promising applications to remove oil spills in real life, especially for marine crude oil spills. © 2018 Wiley Periodicals, Inc. J. Appl. Polym. Sci. 2019, 136, 47052.
scite is a Brooklyn-based organization that helps researchers better discover and understand research articles through Smart Citations–citations that display the context of the citation and describe whether the article provides supporting or contrasting evidence. scite is used by students and researchers from around the world and is funded in part by the National Science Foundation and the National Institute on Drug Abuse of the National Institutes of Health.
hi@scite.ai
10624 S. Eastern Ave., Ste. A-614
Henderson, NV 89052, USA
Copyright © 2024 scite LLC. All rights reserved.
Made with 💙 for researchers
Part of the Research Solutions Family.