Supramolecular Materials最新文献

Multidrug resistance significantly impedes the efficacy of cancer chemotherapy. Resistance often arises from the reduced cellular uptake of chemotherapeutic drugs, a process crucial for their cytotoxic effects. This reduction is frequently due to transmembrane efflux pumps powered by ATP from mitochondria and the cytoplasmic matrix, leading to lower intracellular concentrations of these drugs. This study introduces an amphiphilic molecule, bis(zinc-dipicolylamine) farnesol (Bis-ZnDPA), which targets phosphatidylserine (PS) – a negatively charged phospholipid prominently displayed on the outer leaflet of cancer cell plasma membranes. Integrating the hydrophobic segment of Bis-ZnDPA into the plasma membrane disrupts its integrity, potentially leading to hole formation and facilitating the uptake of chemotherapeutic drugs. Furthermore, the binding of Bis-ZnDPA to phosphatidylserine inhibits ATP production caused by Ca²⁺ influx and deregulation of the phosphoinositide 3-kinase/protein kinase B (PI3K/AKT) signaling pathway, reducing the efflux of drugs from cells. The results indicate the potent synergistic effect of Bis-ZnDPA with chemotherapeutic agents, suggesting that targeting PS is a viable strategy for overcoming multidrug resistance in cancer chemotherapy.

Stretchable lithium-ion batteries (LIBs) are highly desirable to serve as the power sources of stretchable and wearable electronic devices. Furthermore, endowing stretchable LIBs with self-healability can prolong their life-time and enhance their reliability. However, previously reported self-healable LIBs were flexible rather than stretchable, while the stretchable LIBs were unable to self-heal. Herein, we present a novel strategy to fabricate stretchable and self-healable LIBs with all-in-one configuration, by exploiting dynamic covalent polymers as both the electrolyte and the binder of electrodes. The developed polymer electrolyte exhibits a room-temperature ionic conductivity as high as 3.6 × 10⁻⁴ S cm⁻¹ and possesses an elongation-at-break of 250 ± 30 %. Moreover, the stretchable electrolyte is highly resilient and its ionic conductivity shows minimal changes at different strains. The electrolyte exhibits an autonomous self-healing property at room temperature, making the cut sample easily recover its original performance. Importantly, the electrolyte and electrodes can be fused together at the interface to construct a healable LIB with all-in-one configuration, through the exchange of the dynamic imine bonds that exist in both the electrolyte and electrodes. As a result, the as-developed LIB possesses an elongation-at-break of 220 ± 20 % and can supply power in the course of stretching and releasing. Furthermore, the cut and then healed LIB can still deliver an average discharge capacity of 126.4 mAh g ^{− 1} and steadily provide power for LED. This work offers a new avenue for the development of stretchable and self-healable LIBs for the stretchable and wearable electronic devices.

Dynamic covalent bonds (DCBs) have received significant interest due to their unique reversibility and stimuli-responsiveness. The introduction of DCBs provides materials with self-healing and controllable load and release properties, which result in the emergence of widespread applications in biomedical disciplines. In this minireview, we first introduce the chemistry nature and reaction characteristics of different types of DCBs followed by discussing the design strategies of DCB materials. Finally, we summarize the latest progress about the biomedical applications, including drug delivery, enzyme regulation, molecule recognition and detection, wound healing, biosensing and cell culture, and propose some challenges in the future development of DCB biomaterials.

The multiple hydrogen-bond has been introduced as a reversible driving force for directing the assembly of polymer-grafted nanoparticles (PGNPs). The complementary hydrogen-bonds among the polymer ligands lead to the spontaneous aggregation of PGNPs. However, it may also induce the uncontrollable aggregation of PGNPs into assemblies with non-uniform size, even irregular precipitates, due to the immoderate agglomeration associated with the strong interactions of multiple hydrogen-bonds. This severely limits the stable dispersion of PGNP aggregates in a solvent and their applications. In this work, the gold nanoparticles (AuNPs) grafted with thymine-terminated polystyrene (AuNP@PS-Thy) and diaminopyridine-terminated polystyrene (AuNP@PS-Dap) were synthesized, respectively. Their thermal-responsive assembly behavior in an organic solvent was systematically studied. By optimizing the assembly conditions, i.e., the concentration of PGNPs and the incubation time, the assemblies of AuNP@PS-Thy/AuNP@PS-Dap with controllable size were obtained. Interestingly, the assemblies deposited on a solid substrate showed excellent photothermal antimicrobial activities under irradiation of 808 nm and 655 nm lasers. The killing percentage of Staphylococcus aureus (S. aureus) and Escherichia coli (E. coli) could reach 99 % after irradiating for 10 min. This work establishes an approach for controlling the hydrogen-bonding-induced assembly behavior of PGNPs, which may be extended to construct functional metamaterials with controllable structures.

Protein products perform important roles in the biochemistry field, but the thermal inactivation of proteins will increase the difficulty of their transport, storage and application. Therefore, improving the thermal stability of proteins has become a thorny challenge. Natural molecular chaperones can efficiently improve the resistance of proteins to environmental stimuli by reversible supramolecular assembly with proteins. Inspired by this machine, herein we designed a nanochaperone (nChap) with thermo-responsive amphiphilic surfaces that can prevent thermal denaturation and facilitate refolding of green fluorescent proteins (GFPs). By mimicking the hydrophobic microregion of natural chaperones, this nChap can effectively capture free GFPs and hide them into surface confined spaces, thereby shielding exposed hydrophobic sites of GFPs and preventing their irreversible thermal aggregation. When the heat stimulation disappeared, the thermosensitive segments of the nChaps underwent the hydrophilic transition, which provided suitable microenvironments for GFPs refolding. More importantly, nChaps could also actively adsorb to the surface of immobilized GFPs at high temperatures and realize the satisfactory dissociation of the nChap-protein complex upon cooling, which exhibited excellent chaperone-like activity. This work provides significant insights for understanding and developing strategies to improve protein stability.

Chemodynamic therapy, which relies on the generation of cytotoxic radicals, can be amplified by a nanoplatform that produces hydroxyl radicals while also compromising natural radical scavenging mechanisms. For this purpose, a well-defined amphiphilic terpolymer, poly(oligo(ethylene glycol) monomethyl ether methacrylate)-block-poly(N,N-dimethyl aminoethyl methacrylate-statistical-monomer bearing ferrocene graft via azobenzene linker) (POEGMA-b-P(DMAEMA-st-(M-Azo-Fc), denoted as PAzo-Fc) is prepared by a consecutive reversible addition-fragmentation chain transfer (RAFT) polymerization technique, and is further used for doxorubicin (DOX) encapsulation to afford DOX-loaded stabilized nanomicelles, DOX@PAzo-Fc with an average hydrodynamic diameter of 86.0 nm. DOX@PAzo-Fc shows a self-cascade property for amplified CDT. That is, Azo cleavage-induced glutathione (GSH) depletion alleviates reactive oxygen species (ROS) scavenging. Together with the DOX-enhanced hydrogen peroxide generation, the Fc-mediated Fenton reaction is boosted for enhanced CDT. More importantly, the resulting amplified cascade chemo-chemodynamic therapy exerts a synergistic immunogenic cell death (ICD) enhancement effect for effective cancer immunotherapy, which further resulted in a high tumor inhibition rate of 87.8 % in murine tumor models. The uniqueness of this study is the construction of a minimalist nanoplatform based on M-Azo-Fc units for amplified CDT via simultaneously producing hydroxyl radicals and compromising natural radical scavenging mechanisms. Overall, this self-cascade terpolymer platform fabricated herein offers a facile yet robust approach for advanced combinatory cancer therapy with great potential for clinical translations.

Aggregation-induced emission (AIE) luminogens show great potential in many applications. In this study, we have synthesized diblock copolymers poly (ethylene glycol) -b-poly (9-anthrylmethyl-_L-lysine) (PEG-b-PLLys-An) and poly (ethylene glycol) -b-poly (9-anthrylmethyl-_D-lysine) PEG-b-PDLys-An with opposite handedness by ring-opening polymerization and post-modification. Both diblock copolymers can self-assemble into spherical micelles or planar connected disc-like aggregates at different water fractions. In addition, the copolymers present a typical AIE process concomitant with the self-assembly process. To facilitate the study of chain exchange kinetics, we develope a novel visualizable strategy based on fluorescence variation. This strategy allows us to monitor the real-time chain exchange process by mixing equimolar solutions of PEG₄₄-b-PDLys₂₀-An and PEG₄₄-b-PLLys₂₀-An with varying water volume fractions. We indicate that chain exchange predominantly occurs at low water fractions through a single-molecule extraction and redistribution mechanism rather than micellar fission and fusion. In contrast, the micelles appear to be "kinetically frozen" at high water fractions, suggesting suppressed chain exchange under these conditions. Importantly, our approach offers a visually observable method for probing the dynamics of micellar chain exchange in real time.

Fluorescence sensing converts chemical events into measurable readings by utilizing fluorescence signals for the qualitative or quantitative detection of specific analytes. Supramolecular chemistry, reliant upon non-covalent interactions, has emerged as a potent paradigm for sensing applications, garnering significant scholarly attention. The adoption of supramolecular chemistry within the realm of sensing offers several significant advantages, including easy construction, rapid response, dynamic reversibility, and compatibility with pattern recognition. Notably, molecular recognition stands as a pivotal facet of supramolecular sensing. Among the integral constituents of supramolecular chemistry, an array of macrocyclic compounds boasts remarkable molecular recognition properties, apt for diverse guest molecules, and finds extensive utility in fluorescence sensing. This review highlights the pivotal contributions of fluorescent sensors rooted in crown ethers, cyclodextrins, calixarenes, cucurbiturils, and other macrocycles in single sensing, differential sensing and bioimaging. The versatility of these sensors extends to diverse media, encompassing aqueous environments, buffer solutions, and biofluid matrices. Additionally, this review provides insights into the future endeavors and forthcoming research directions in the field of supramolecular sensing and imaging.

Bacterial infections arising from antibiotic-resistant strains represent a formidable global health threat. In the realm of antibacterial therapies, supramolecular hydrogels stand out with unique advantages owing to their adaptable and flexible non-covalent interactions with diverse biomolecules. Their ability to encapsulate a variety of biologically active agents through co-assembly further amplifies their efficacy, endowing these hybrid hydrogels with a spectrum of functionalities within a unified system. Various functionalities encompass self-healing, injectability, tissue adhesion, facile drug loading, controlled release mechanisms, biocompatibility, antibacterial properties, and antioxidative attributes. This review article delves into two categories of supramolecular antibacterial hydrogels: i) those with intrinsic antibacterial attributes and ii) supramolecular co-assembled hybrid hydrogels formed through the integration of hydrogels with an assortment of active antibacterial agents, including various nanomaterials, antibiotics, biologically active compounds derived from natural sources, and antibacterial polymers. The anticipated role of supramolecular co-assembled hybrid hydrogels, coupled with contemporary medical technologies and devices, is paramount in the development of highly effective and secure platforms for antibacterial therapy. Furthermore, review addresses the current challenges in the realm of antibacterial hydrogels while elucidating prospective future advancements in this field.

Cortical bone has superior mechanical performance. Hydroxyapatite (HA) as its main component are attractive bioactive materials, but possess weak strength. The critical factor is the difference in the structure. Inspired by the hierarchical and delicate architecture of the cortical bone, we used a slurry with 2 wt% polyvinyl alcohol (PVA) and 20 vol% polydopamine-modified nano HA (nHA, pDA-nHA) to fabricate stronger scaffolds characterized by a lamellar structure. Additionally, we immersed the pDA-nHA scaffolds into the polyetherketoneketone (PEKK) synthesis system to reinforce the scaffolds. The cortical bone-inspired composites were produced successfully, and the 20 vol% pDA-nHA+2 wt% PVA/PEKK composites had the highest strength and modulus. It provides a new solution for enhancing the mechanical strength of the single component, as well as improving the bioactivity of PEKK.