Supramolecular Self-assembly Research Articles

NiCoP cocatalyst modified g-C3N4 as ohmic junction photocatalyst for efficient degradation of tetracycline under visible light

Increasing the electron-hole recombination rate in g-C3N4 can effectively improve its photocatalytic performance. In this work, NiCoP/g-C3N4 (NCP/PCN) composites with ohmic junction were formed by embedding granular NiCoP in irregularly porous g-C3N4. There was almost no barrier between the metal and the semiconductor in ohmic junction, which made it easier for electrons to slip from PCN to NCP along the curved energy band, and NCP acted as an electron collector to rapidly capture the slipping electrons. In addition, porous g-C3N4 prepared by supramolecular self-assembly could provide a shorter diffusion path for electrons. Thus, the electron-hole was effectively separated and the photocatalytic performance was improved. The band electronic structure and existence of ohmic junction in 7-NCP/PCN composite were demonstrated by XPS, ESR and DFT calculation. Finally, a reasonable photocatalytic degradation mechanism and possible tetracycline degradation path were proposed. This work has significant potential for providing an effective method for the design of non-precious metal photocatalysts.

Global advances and smart innovations in supramolecular polymers

Supramolecular polymer represents a transformative frontier in materials science, reshaping polymer technology through unique assembly principles and dynamic properties. This manuscripts delves into the rapid advancements and future potential within this field, examining the theoretical foundations of supramolecular interactions and self-assembly that constitute these polymers. It progresses to explore state-of-the-art synthesis and design strategies that enhance the functionality of these complex materials. Particularly notable is the integration of supramolecular polymers with nanotechnology, fostering advancements that deepen our understanding and application in significant ways. The reported work showcases the adaptability of supramolecular polymers across various domains, including groundbreaking roles in drug delivery and tissue engineering within biomedical engineering, and as innovative agents for environmental purification and sensor development. The discussion also addresses current challenges such as stability, scalability, and reproducibility, central to transitioning from research to real-world applications. This state-of synthetic knowledge not only provides a comprehensive examination of the current status of supramolecular polymer research but also encourages further investigation and innovation, with the anticipation that these materials will revolutionize multiple industries with their inherent versatility and capacity for sustainability.

RADA-16-based Self-assembled Peptide Nanofiber Scaffolds Loaded with TGF-β1 Enhance the Chondrogenic Differentiation Potential of BMSCs In vitro.

At present, cartilage repair does not offer ideal efficacy. Fortunately, recent studies have claimed that RADA-16 peptide is an attractive therapeutic strategy for repairing cartilage defects. Therefore, this study tried to explore the effect of RADA-16 loaded with transforming growth factor-beta (TGF-β) 1 on cartilage differentiation of bone marrow mesenchymal stem cells (BMSCs). First, the RADA-16 peptide was synthesized by solid phase peptide, and a well-defined hydrogel was formed by supramolecular peptide self-assembly. Then, TGF-β1 (loading concentration of 10 ng/mL) was loaded into RADA-16, with scanning electron microscopy to observe the morphology of the TGF-β1/RADA-16 hydrogel and detect its related properties. Next, BMSCs were isolated from bone marrow samples and identified. TGF-β1/RADA-16 was co-cultured with L929, BMSCs, and C28/I2 cells, respectively, and the survival and proliferation ability of the cells was determined by live/dead cell staining and MTT assay. Chondrogenic differentiation and sGAG production of BMSCs were determined by Alcian blue staining and Blyscan assay, the expression of cartilage-associated genes by qRT-PCR, and the levels of inflammatory factors by ELISA. As for mechanism investigation, the Smad and ERK/MAPK signaling pathways were detected by western blot. RADA-16 hydrogel exhibited a well-distributed and interconnected porous surface structure, with a loading rate of 91.9% for TGF-β1. The TGF-β1/RADA-16 hydrogel had good release and degradation properties, and had no negative effect on the survival and proliferation ability of BMSCs, L929, and C28/I2 cells. Importantly, TGF-β1/RADA-16 hydrogel significantly accelerated chondrogenic differentiation and sGAG generation in BMSCs, and decreased pro-inflammatory factor production. In addition, the hydrogel also significantly activated the Smad and ERK/MAPK pathways of BMSCs. RADA-16 loaded with TGF-β1 has good biological properties and can enhance the chondrogenic differentiation ability of BMSCs.

Multiple Cations Nanoconfinement in Ultrathin V2O5 Nanosheets Enables Ultrafast Ion Diffusion Kinetics Toward High-performance Zinc Ion Battery.

Nanoconfinement of cations in layered oxide cathode is an important approach to realize advanced zinc ion storage performance. However, thus far, the conventional hydrothermal/solvothermal route for this nanoconfinement has been restricted to its uncontrollable phase structure and the difficulty on the multiple cation co-confinement simultaneously. Herein, this work reports a general, supramolecular self-assembly of ultrathin V2O5 nanosheets using various unitary cations including Na+, K+, Mg2+, Ca2+, Zn2+, Al3+, NH4 +, and multiple cations (NH4 + + Na+, NH4 + + Na+ + Ca2+, NH4 + + Na+ + Ca2+ +Mg2+). The unitary cation confinement results in a remarkable increase in the specific capacity and Zn-ion diffusion kinetics, and the multiple cation confinement gives rise to superior structural and cycling stability by multiple cation synergetic pillaring effect. The optimized diffusion coefficient of Zn-ion (7.5 × 10-8 cm2 s-1) in this assembly series surpasses most of the V-based cathodes reported up to date. The work develops a novel multiple-cations nanoconfinement strategy toward high-performance cathode for aqueous battery. It also provides new insights into the guest cation regulation of zinc-ion diffusion kinetics through a general, supramolecular assembly pathway.

Fabrication of Mesoporous Materials Based on Supramolecular Self-Assembly of Guanosine Monophosphonate-Nickel Chloride (GMP-Ni) for High-Performance Hybrid Supercapacitors.

Supramolecular self-assembly of nickel chloride and guanosine mono-phosphonate (GMP) and nickel (Ni)-based GMP-Ni and their calcinated mesoporous electrode materials GMP-Ni-500 and GMP-Ni-700 at 500 and 700 °C, respectively, have been fabricated. GMP-Ni, GMP-Ni-500, and GMP-Ni-700 are examined for their supercapacitor performance in a three-electrode configuration. The electrochemical tests demonstrate the mesoporous battery-type nature of GMP-Ni-500 which exhibited a specific capacity (Cs) of about 289 C g-1 at 0.5 A g-1 current density. In addition, a cost-effective and simple asymmetric supercapacitor device has been fabricated with battery-type GMP-Ni-500 as a cathode material and capacitive-type activated carbon (AC) as an anodic material. In an operating voltage window of 0 to 1.5 V, hybrid supercapacitors (HSCs) based on GMP-Ni-500//AC exhibited a remarkable performance with a specific capacity (Cs) of 144 C g-1 at 0.5 A g-1. For the HSC device, the maximum of 66% capacity retention has been observed after 5000 charging/discharging cycles at 5 A g-1. Furthermore, the HSC device demonstrates a high energy density of 24 W h kg-1 at a power density of 297 W kg-1. The molecular transformation was established by employing theoretical calculations. These results suggest that our HSC has outstanding potential in technology development for next-generation commercial applications.

Supramolecular Engineering of Ti3C2Tx MXene -Perylene Diimide Hybrid Electrodes for the Pseudocapacitive Electrochemical Storage of Calcium Ions.

The rare combination of metallic conductivity and surface redox activity enables 2D MXenes as versatile charge storage hosts for the design of high-rate electrochemical energy storage devices. However, high charge density metal ions including but not limited to Ca+2 and Mg+2 pose challenges such as sluggish solid-state diffusion and also inhibiting the charge transfer across electrode-electrolyte interfaces. In this work, free-standing hybrid electrode architectures based on 2D titanium carbide-cationic perylene diimide (Ti3C2Tx@cPDI) via supramolecular self-assembly are developed. Secondary bonding interactions such as dipole-dipole and hydrogen bonding between Ti3C2Tx and cPDI are investigated by zeta potential and Fourier-transformed infrared (FTIR) spectroscopy . Ti3C2Tx@cPDI free-standing electrodes show typical volumetric capacitance up to 260 F cm-3 in Mg2+ and Ca2+ aqueous electrolytes at charging times scales from 3minutes to a few seconds. Three-dimensional (3D) Bode maps are constructed to understand the charge storage dynamics of Ti3C2Tx@cPDI hybrid electrode in an aqueous Ca-ion electrolyte. ,Pseudocapacitance is solely contributed by the nanoscale distribution of redox-active cPDI supramolecular polymers across 2D Ti3C2Tx. This study opens avenues for the design of a wide variety of MXene@redox active organic charge hosts for high-rate pseudocapacitive energy storage devices.

Synergistic antibacterial effect of the pistachio green hull extract-loaded porphysome decorated with 4-nitroimidazole against bacteria

‘Active targeting’ refers to modifying a nanocarrier’s surface with targeting ligands. This study introduced an efficient approach for immobilizing imidazole-based drugs onto the metallated-porphyrin complex within the porphysome nanocarrier. To enhance cellular and bacterial uptake, a Ni-porphyrin with a fatty acid tail was synthesized and placed in the bilayer center of DPPC, facilitating receptor-mediated endocytosis. The Ni-porphyrin in the head group of the Ni-porphyrin-tail was placed superficially in the polar region of the membrane. Spherical unilamellar vesicle formation (DPPC: Ni-porphyrin-tail 4:1 mole ratio), as metallo-porphysome, was achieved through supramolecular self-assembly in an aqueous buffer. These vesicles exhibited a diameter of 279 ± 7 nm and a zeta potential of −15.3 ± 2.5 mV, showcasing their unique cytocompatibility. Nitroimidazole was decorated on the surface of metallo-porphysomes and pistachio green hull extract (PGHE) was loaded into the carrier for synergistic activity against (E. coli) and (S. aureus) bacteria strains. The physicochemical properties of Nitroimidazole-porphysome-PGHE, including size, zeta potential, morphology, loading efficiency, and release profile under various pH and temperature conditions in simulated gastrointestinal fluids were characterized. This combination therapy prevented bacterial cell attachment and biofilm formation in Caco-2 cells, as colon epithelial cells. The remarkable benefit of this system is that it does not affect cell viability even at 0.5 mg/ml. This study demonstrates the potential of a new co-delivery system using biocompatible metallo-porphysomes to decrease bacterial infections.

Microemulsion-Assisted Self-Assembly of Indium Porphyrin Photosensitizers with Enhanced Photodynamic Therapy.

Designing and constructing supramolecular photosensitizer nanosystems with highly efficient photodynamic therapy (PDT) is vital in the nanomedical field. Despite recent advances in forming well-defined superstructures, the relationship between molecular arrangement in nanostructures and photodynamic properties has rarely been involved, which is crucial for developing stable photosensitizers for highly efficient PDT. In this work, through a microemulsion-assisted self-assembly approach, indium porphyrin (InTPP) was used to fabricate a series of morphology-controlled self-assemblies, including nanorods, nanospheres, nanoplates, and nanoparticles. They possessed structure-dependent 1O2 generation efficiency. Compared with the other three nanostructures, InTPP nanorods featuring strong π-π stacking, J-aggregation, and high crystallinity proved to be much more efficient at singlet oxygen (1O2) production. Also, theoretical modeling and photophysical experiments verified that the intermolecular π-π stacking in the nanorods could cause a decreased singlet-triplet energy gap (ΔEST) compared with the monomer. This played a key role in enhancing intersystem crossing and facilitating 1O2 generation. Both in vitro and in vivo experiments demonstrated that the InTPP nanorods could trigger cell apoptosis and tumor ablation upon laser irradiation (635 nm, 0.1 W/cm2) and exhibited negligible dark toxicity and high phototoxicity. Thus, the supramolecular self-assembly strategy provides an avenue for designing high-performance photosensitizer nanosystems for photodynamic therapy and beyond.

Cucurbit[8]uril-Based Supramolecular Probe for the Detection of 3-Nitrotyrosine in Human Serum and Plasma.

The biomarker 3-nitrotyrosine (3-NT) is widely recognized as an indicator of renal oxidative stress injury, making its detection crucial for the early identification of renal insufficiency. This study presents the design and synthesis of a tetraphenylstyrene imidazole derivative (TIPE-MI), which is utilized to create a supramolecular probe in conjunction with cucurbit[8]uril (Q[8]) through host-guest interactions. The resulting supramolecular self-assembly exhibits excellent optical properties and has been employed for the specific detection of 3-NT through fluorescence quenching. The introduction of 3-NT resulted in a decreased fluorescence intensity of the yellow fluorescent probe, which gradually transitioned from bright yellow to light yellow and then became colorless as the 3-NT concentration was increased. A portable detection platform was devised to augment the efficiency of detection. In order to facilitate biological applications, we have substantiated the probe's exceptional precision in detecting 3-NT in biological samples, encompassing human serum and plasma. The probe also exhibited negligible cytotoxicity. The accumulation of the probe in renal cells elicited a fluorescence signal, thereby indicating the prospective viability of this system for visual detection with renal cytocompatibility.

Immunopotentiating Polyphosphazene Delivery Systems: Supramolecular Self-Assembly and Stability in the Presence of Plasma Proteins.

Studies on the biological performance of nanomedicines have been increasingly focused on the paradigm shifting role of the protein corona, which is imminently formed once the formulation is placed in a complex physiological environment. This phenomenon is predominantly studied in the context of protein adsorption science, while such interactions for water-soluble systems remain virtually unexplored. In particular, the importance of plasma protein binding is yet to be understood for pharmaceuticals designed on the basis of supramolecular architectures, which generally lack well-defined surfaces. Water-soluble ionic polyphosphazenes, clinically proven immunoadjuvants and vaccine delivery vehicles, represent an example of a system that requires supramolecular coassembly with antigenic proteins to attain an optimal immunopotentiating effect. Herein, the self-assembly behavior and stability of noncovalently bound complexes on the basis of a model antigen─hen egg lysozyme─and polyphosphazene adjuvant are studied in the presence of plasma proteins utilizing isothermal calorimetry, asymmetric flow field flow fractionation, dynamic light scattering, and size exclusion chromatography methods. The results demonstrate that although plasma proteins, such as human serum albumin (HSA), show detectable avidity to polyphosphazene, the strength of such interactions is significantly lower than that for the model antigen. Furthermore, thermodynamic parameters indicate different models of binding: entropy driven, which is consistent with the counterion release mechanism for albumin versus electrostatic interactions for lysozyme, which are characterized by beneficial enthalpy changes. In vitro protein release experiments conducted in Franz diffusion cells using enzyme-linked immunoassay detection suggest that the antigen-adjuvant complex stability is not adversely affected by the presence of the most physiologically abundant protein, which confirms the importance of the delivery modality for this immunoadjuvant. Moreover, HSA shows an unexpected stabilizing effect on complexes with high antigen load─an important consideration for further development of polyphosphazene adjuvanted vaccine formulations and their functional assessment.

Mitochondrial Localized In Situ Self-Assembly Reprogramming Tumor Immune and Metabolic Microenvironment for Enhanced Cancer Therapy.

The inherent immune and metabolic tumor microenvironment (TME) of most solid tumors adversely affect the antitumor efficacy of various treatments, which is an urgent issue to be solved in clinical cancer therapy. In this study, a mitochondrial localized in situ self-assembly system is constructed to remodel the TME by improving immunogenicity and disrupting the metabolic plasticity of cancer cells. The peptide-based drug delivery system can be pre-assembled into nanomicelles in vitro and form functional nanofibers on mitochondria through a cascade-responsive process involving reductive release, targeted enrichment, and in situ self-assembly. The organelle-specific in situ self-assemblyeffectively switches the role of mitophagy from pro-survival to pro-death, which finally induces intense endoplasmic reticulum stress and atypical type II immunogenic cell death. Disintegration of the mitochondrial ultrastructure also impedes the metabolic plasticity of tumor cells, which greatly promotes the immunosuppresive TME remodeling into an immunostimulatory TME. Ultimately, the mitochondrial localized in situ self-assembly system effectively suppresses tumor metastases, and converts cold tumors into hot tumors with enhanced sensitivity to radiotherapy and immune checkpoint blockade therapy. This study offers a universal strategy for spatiotemporally controlling supramolecular self-assembly on sub-organelles to determine cancer cell fate and enhance cancer therapy.

Supramolecular Self-Assembly of Proteins Promoted by Hybrid Polyoxometalates.

Controlling the formation of supramolecular protein assemblies and endowing them with new properties that can lead to novel functional materials is an important but challenging task. In this work, a new hybrid polyoxometalate is designed to induce controlled intermolecular bridging between biotin-binding proteins. Such bridging interactions lead to the formation of supramolecular protein assemblies incorporating metal-oxo clusters that go from several nanometers in diameter up to the micron range. Insights into the self-assembly process and the nature of the resulting biohybrid materials are obtained by a combination of Small Angle X-ray Scattering (SAXS), Transmission Electron Microscopy (TEM), and Dynamic Light Scattering (DLS), along with fluorescence, UV-vis, and Circular Dichroism (CD) spectroscopy. The formation of hybrid supramolecular assemblies is determined to be driven by biotin binding to the protein and electrostatic interactions between the anionic metal-oxo cluster and the protein, both of which also influence the stability of the resulting assemblies. As a result, the rate of formation, size, and stability of the supramolecular assemblies can be tuned by controlling the electrostatic interactions between the cluster and the protein (e.g., through varying the ionic strength of the solution), thereby paving the way toward biomaterials with tunable assembly and disassembly properties.

Citric acid/chitosan adhesive with viscosity-controlled for wood bonding through supramolecular self-assembly

Developing bio-based sustainable wood adhesives is significant as a substitute for petroleum-derived adhesives. However, the existing bio-based adhesives have disadvantages of complex fabrication, uncontrollable viscosity, and poor water resistance. Herein, we developed a citric acid/chitosan adhesive with viscosity-controlled and water-resistant features by one-step dissolution at room temperature based on the supramolecular self-assembly strategy. Different wood products (plywood, laminated veneer lumber and particleboard) with superior performance were prepared by applying that adhesive on veneer and wood particles (fine and rough particles). The plywood test results showed that the citric acid/chitosan adhesive had dry and wet shear strengths outperforming the China National Standard (GB/T 9846-2015, ≥0.7 MPa), reaching 2.1 and 1.1 MPa, respectively. The adhesion mechanism was mechanical interlocks and cross-linking of citric acid/chitosan in adhesives with those in the cell wall. This work provides high promise for alternatives to traditional unsustainable wood adhesives (urea-formaldehyde, melamine-urea-formaldehyde and phenolic resins) for fabricating different wood products.

Host-guest assembly triggered lower critical solution temperature behavior with reversible photo-regulation

The less frequent lower critical solution temperature (LCST) phenomenon has attracted extensive attention due to the foresighted application in smart materials. Nevertheless, the existing LCST-type materials are mainly dominated by a few polymers with specific moieties due to the damped hydration at a higher temperature and the lack of reversible regulations of the corresponding temperature sensitivity. Herein, an unanticipated and reversibly photo-responsive LCST behavior was uncovered in the BSC4/Azo-4 assembly solution. Such behavior arose from the host-guest binding between BSC4 and Azo-4 in an aqueous solution since neither the guest nor host alone exhibited an LCST property. Ascribing to the distinct π-π stacking between the trans- and cis-isomers of Azo-4, a reversible regulation of LCST behavior was achieved by irradiating UV and blue light alternately. Our study demonstrated the complexity and possibility of supramolecular self-assembly, opening a new avenue in the fabrication and adjustment of LCST-type materials in the future.

Construction of supramolecular self-assembly of cyclobutanocucurbit[5]uril and six aromatic amines

Supramolecular self-assemblies are molecular aggregates formed by the combination of multiple molecules via intermolecular noncovalent bonding interactions. The synergy of hydrogen bonds and weak intermolecular interactions endows them with specific structures and functionalities. In this paper, 1H NMR spectroscopy, HPLC-QTOF mass spectrometry and other characterization methods were used to investigate the interaction modes of cyclobutanocucurbit[5]uril (CyB5Q[5]) and six aromatic amine compounds. The results showed that the negative electrostatic portal carbonyls of CyB5Q[5] interacted with the guest molecules via hydrogen bonding. The benzene ring in the guest molecules interacted with the methylene groups on the outer surface of CyB5Q[5] via CH···π interactions. [ZnCl4]2– anions acted as a structure-directing agent and participated in the ion-dipole interactions with the positive electrostatic outer surface of CyB5Q[5]. Three weak intermolecular interactions synergistically constructed a series of multi-level supramolecular self-assembly materials.

A natural food-grade supramolecular self-assembly system for creation of hierarchically structured hydrogels.

We develop a novel hierarchically structured hydrogel by the supramolecular self-assembly of all-natural food-grade building blocks, glycyrrhizic acid (GA) and carrageenan (CG). The co-assembled GA-CG hydrogel system displays an unusual structural transition with the appearance from opacity to translucence and then to opacity, as a function of the concentration of metal ions. The unique GA-CG supramolecular hydrogel system can serve as solid, edible, and responsive active cargo delivery platforms for food and biomedical applications.

Solvent-induced supramolecular self-assembly in a solid-state A1/A2-difunctionlized pillar[5]arene host

Herein we report the influence of the crystallization solvent in the supramolecular self-assembly in the solid-state of an A1/A2-difunctionlized pillar[5]arene host.

In situ supramolecular self-assembly of a perylene diimide derivative in mitochondria for cancer cell ferroptosis

An in situ supramolecular self-assembly system that could lead to the ferroptosis of cancer cells was successfully constructed in mitochondria.

Supramolecular self-assembled gold nanoparticle clusters for synergistic photothermal-chemo tumor therapy.

The combination of photothermal therapy and chemotherapy has emerged as a promising strategy to improve cancer therapeutic efficacy. However, developing a versatile nanoplatform that simultaneously possesses commendable photothermal effect and high drug encapsulation efficiency remains a challenging problem yet to be addressed. Herein, we report a facile supramolecular self-assembly strategy to construct gold nanoparticle clusters (AuNCs) for synergistic photothermal-chemo therapy. By utilizing the functional polysaccharide as a targeted ligand, hyaluronic acid-enriched AuNCs were endowed with targeting CD44 receptor overexpressed on the B16 cancer cells. Importantly, these hyaluronic acid modified AuNCs can shelter therapeutic cargo of doxorubicin (DOX) to aggregate larger nanoparticles via a host-guest interaction with the anchored β-cyclodextrin, as a "nanocluster-bomb" (DOX@AuNCs). The in vitro results revealed that these DOX@AuNCs showed light-triggered drug release behavior and synergistic photothermal-chemo therapy. The improved efficacy of synergistic therapy was further demonstrated by treating a xenografted B16 tumor model in vivo. We envision that our multipronged design of DOX@AuNCs provides a potent theranostic platform for precise cancer therapy and could be further enriched by introducing different imaging probes and therapeutic drugs as appropriate suitable guest molecules.

Exploring multi-stimuli-responsive Pt(ii) complexes: supramolecular self-assembly, lysosome-specific targeted photodynamic therapy and photodegradation of organic pollutants

Developing novel luminescent materials with multi-stimuli-responsiveness and multi-functional properties is vital.