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Efficient interactions between an adhesive and a substrate surface at the molecular level are the basis for the formation of robust adhesion, which substantially relies on interfacial wetting. However, strong adhesives usually improve cohesion but compromise interfacial properties. Herein, we have reported a kind of robust supramolecular adhesive based on the outstanding mobility and interfacial wettability of adhesive precursors. In situ fast photopolymerization endows supramolecular adhesives with more outstanding adhesion for both smooth and rough surfaces in air and underwater in contrast to their counterparts from thermal polymerization. In addition to their low viscosity and high monomer concentration, supramolecular adhesive precursors without any organic solvents possess well-defined hydrogen bonding interactions. These superior properties consistently contribute to the wetting of the substrate and the formation of adhesive polymers with high molecular weights. This work highlights that enhancing interfacial wetting between an adhesive and a substrate is a promising route to achieving robust adhesion.
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Glycopolymer-based supramolecular glycoassemblies with signal-driven cascade morphological deformation and accessible surface engineering toward bioinspired functional glycomaterials have attracted much attention due to their diverse applications in fundamental and practical scenarios. Herein, we achieved the cascade morphological transformation and surface engineering of a nucleobase-containing polymeric glycovesicle through exploiting the bioinspired complementary multiple hydrogen bonds of complementary nucleobases. First, the synthesized thymine-containing glycopolymers (PGal30-b-PTAm249) are capable of self-assembling into well-defined glycovesicles. Several kinds of amphiphilic adenine-containing block copolymers with neutral, positive, and negative charges were synthesized to engineer the glycovesicles through the multiple hydrogen bonds between adenine and thymine. A cascade of morphological transformations from vesicles to ruptured vesicles with tails, to worm-like micelles, and finally to spherical micelles were observed via continuously adding the adenine-containing polymer into the thymine-containing glycovesicles. Furthermore, the surface charge properties of these glyconano-objects can be facilely regulated through incorporating various adenine-containing polymers. This work demonstrates the potential application of a unique bioinspired approach to precisely engineer the morphology and surface properties of glycovesicles for boosting their biological applications.
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Micelas , Timina , Enlace de Hidrógeno , Polímeros/química , Adenina/químicaRESUMEN
Glycopolymer-supported silver nanoparticles (AgNPs) have demonstrated a promising alternative to antibiotics for the treatment of multidrug-resistant bacteria-infected diseases. In this contribution, we report a class of biohybrid glycopolymersome-supported AgNPs, which are capable of effectively killing multidrug-resistant bacteria and disrupting related biofilms. First of all, glycopolymersomes with controllable structures were massively fabricated through reversible addition-fragmentation chain transfer (RAFT) polymerization-induced self-assembly (PISA) in an aqueous solution driven by complementary hydrogen bonding interaction between the pyridine and amide groups of N-(2-methylpyridine)-acrylamide (MPA) monomers. Subsequently, Ag+ captured by glycopolymersomes through the coordination between pyridine-N and Ag+ was reduced into AgNPs stabilized by glycopolymersomes upon addition of the NaBH4 reducing agent, leading to the formation of the glycopolymersome@AgNPs biohybrid. As a result, they showed a wide-spectrum and enhanced removal of multidrug-resistant bacteria and biofilms compared to naked AgNPs due to the easier adhesion onto the bacterial surface and diffusion into biofilms through the specific protein-carbohydrate recognition. Moreover, the in vivo results revealed that the obtained biohybrid glycopolymersomes not only demonstrated an effective treatment for inhibiting the cariogenic bacteria but also were able to repair the demineralization of caries via accumulating Ca2+ through the recognition between carbohydrates and Ca2+. Furthermore, glycopolymersomes@AgNPs showed quite low in vitro hemolysis and cytotoxicity and almost negligible acute toxicity in vivo. Overall, this type of biohybrid glycopolymersome@AgNPs nanomaterial provides a new avenue for enhanced antibacterial and antibiofilm activities and the effective treatment of oral microbial-infected diseases.
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Nanopartículas del Metal , Plata , Plata/farmacología , Plata/química , Nanopartículas del Metal/química , Antibacterianos/farmacología , Antibacterianos/química , Biopelículas , Bacterias , Carbohidratos/farmacología , Piridinas , Pruebas de Sensibilidad MicrobianaRESUMEN
Owing to the well-established fact that poly(styrenesulfonate) (PSS)-based strong polyelectrolytes are pH insensitive, their applications in smart materials have thus been severely limited. However, we demonstrate here that counterion-mediated hydrogen bonding (CMHB) makes the PSS brush pH-responsive. With decreasing pH, more hydrogen bonds are formed between the bound hydronium counterions and the sulfonate (-SO3-) groups in the PSS brush. At the microscale, the formation of more hydrogen bonds with decreasing pH leads to a more ordered structure and a larger tilt angle of the -SO3- groups in the PSS brush. On the other hand, a range of important physicochemical properties of the PSS brush, including hydration, stiffness, wettability, and adhesion, are responsive to pH, induced by the effect of CMHB on the PSS brush. Our work reveals a clear structure-property relationship for the pH-responsive PSS brush. This work not only provides a new understanding of the fundamental properties of the PSS brush but also greatly extends the applications of PSS-based strong polyelectrolytes.
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Supramolecular polymeric adhesives inspired by nature have been strongly pursued by scientists, since they possess strong but dynamic reversible adhesive behaviors concurrently. Optimizing the adhesive and cohesive properties is of vital importance for the fabrication of strong supramolecular polymeric adhesives, but common strategies often strengthen one property at the expense of another. Herein, counterion exchange of nucleobase-containing polyelectrolyte adhesives was utilized to boost the interfacial adhesion without compromising the intermolecular cohesion, achieving high adhesion strengths. By employing the cationic polyelectrolyte poly(3-acrylamidopropyltrimethylammonium chloride), the slightly enhanced intermolecular cohesion of the polyelectrolyte with hydrophobic sulfonates is capable of enhancing the adhesion strength. Intriguingly, by introducing bioinspired complementary nucleobases within adhesives, the loss of interfacial adhesion was observed for adhesives containing high supramolecular hydrogen-bonding crosslinking densities. By optimizing the cohesive and adhesive properties of nucleobase-containing polyelectrolyte adhesives using sulfonates with suitable chain lengths, 60 to 250 times improvement of adhesion strengths can be attained over that of initial supramolecular polymeric adhesives. Additionally, nucleobase-containing supramolecular polymeric adhesives tolerate different external conditions, maintaining robust adhesion strengths. This work offers us an efficient and feasible way to optimize the cohesive and adhesive properties for constructing robust and tunable supramolecular adhesives.
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The counterion-mediated hydrogen bonding (CMHB) effect can be generated in polyelectrolyte systems when hydrogen bonds are formed between the bound counterions and polyelectrolyte chains. This Perspective mainly discusses the effect of CMHB on polyelectrolytes at the solid/water interface. The CMHB effect generated by the hydroxide (OH-) or hydronium (H3O+) counterions gives rise to a pH responsiveness of strong polyelectrolyte brushes (SPBs) whose strength can be modulated by the external salt concentration. Further studies have shown that the CMHB effect on SPBs can be extended beyond the OH- and H3O+ counterions and that the CMHB effect can be observed in the systems of weak polyelectrolyte brushes (WPBs) and polyelectrolyte multilayers (PEMs). Based on the understanding of the mechanisms of the CMHB effect on polyelectrolytes at the solid/water interface, we have demonstrated that a range of important properties of SPBs, WPBs, and PEMs can be tuned by pH with the consideration of the CMHB effect. Future directions for the CMHB effect on polyelectrolytes are also discussed. The insights on the CMHB effect on polyelectrolytes at the solid/water interface would promote the development of smart interfacial polyelectrolyte materials in a wide range of fields.
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Based on a combination of polymeric redox couples and a polymer hydrogel separator, the performance of aqueous supercapacitors can be improved by concurrently increasing the specific capacitance, widening the electrolyte decomposition window, improving the cycling performance, and suppressing the self-discharge of both the electrical double-layer and faradaic charge storage.
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Transgenic RNA interference (RNAi) represents a burgeoning and promising alternative avenue to manage plant diseases and insect pests in plants. Nonviral nanostructured dsRNA carriers have been demonstrated to possess great potential to facilitate the application of RNAi. However, it remains a critical challenge to achieve the targeted and effective release of dsRNA into the pest cells, limiting the efficiency of the biological control of pests and diseases in practical applications. In this study, we designed and constructed a new type of core-shell polymeric nanostructure (CSPN) with controllable structure, eco-friendliness, and good biocompatibility, on which dsRNA can be efficiently loaded. Once loaded into CSPNs, the dsRNA can be effectively prevented from nonsense degradation by enzymes before entering cells, and it shows targeted and image-guided release triggered by intracellular ATP, which significantly increases the efficiency of gene transfection. Significantly, the in vivo study of the typical lepidoptera silkworm after oral feeding demonstrates the potential of dsCHT10 in CSPNs for a much better knockdown efficiency than that of naked dsCHT10. This innovation enables the nanotechnology developed for the disease microenvironment-triggered release of therapeutic genes for application in sustainable crop protection.
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Insectos , Nanoestructuras , Animales , Insectos/genética , Interferencia de ARN , ARN Bicatenario/genética , Adenosina Trifosfato , Control de InsectosRESUMEN
Polymer-based nanomaterials have exhibited promising alternative avenues to combat the globe challenge of multidrug-resistant bacterial infection. However, most of the reported polymeric nanomaterials have facially linear amphiphilic structures with positive net charges, which may lead to nonspecific binding, high hemolysis, and uncontrollable self-organization, limiting their practical applications. In this contribution, we report a one-dimensional glyconanorod (GNR) through self-assembly of well-defined ß-cyclodextrin-based glycoconjugates (RMan) featuring hydrophobic carbon-based chains and amide rhodamines with an adenosine triphosphate (ATP)-recognition site and targeted and hydrophilic mannoses and positively net-charged ethylene amine groups. The GNRs show superior targeting sensing and killing for Gram-negative Escherichia coli (E. coli) dominantly through the multivalent recognition between mannoses on the nanorod and the lectin on the surface of E. coli. Moreover, red fluorescence was light on due to the hydrogen bonding between amide rhodamine and ATP. Benefiting from the designs, the GNRs are capable of possessing a higher therapeutic index and of encapsulating other antibiotics. They exhibit an enhanced effect against E. coli strains. Intriguingly, the GNRs displayed a more reduced hemolysis effect and lower cytotoxicity compared to that of ethylene glyco-modified nanorods. These results reveal that the glyconanomaterials not only feature superior and targeted bacterial sensing and antibacterial activity, but also better biocompatibility compared with the widely used PEG-covered nanomaterials. Furthermore, the in vivo studies demonstrate that the targeted and ATP-responsive GNRs complexed with antibiotics showed better treatment using a mouse model of abdominal sepsis following intraperitoneal E. coli infection. The present work describes a targeted and effective sensing and antibacterial platform based on glycoconjugates that have potential applications for the treatment of infections caused by pathogenic microorganisms.
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Escherichia coli , beta-Ciclodextrinas , Humanos , Hemólisis , Bacterias , Antibacterianos/farmacología , Antibacterianos/química , Glicoconjugados/farmacología , Glicoconjugados/química , beta-Ciclodextrinas/farmacologíaRESUMEN
A library of 14 dynamic glycopeptide amphiphilic dendrimers composed of 14 hydrophilic and bioactive saccharides (seven kinds) as dendrons and 7 hydrophobic peptides (di- and tetrapeptides) as arms with ß-cyclodextrin (CD) as a core were facially designed and synthesized in several steps. Fourteen saccharides were first conjugated to the C-2 and C-3 positions of CD, forming glycodendrons. Subsequently, seven oligopeptide arms were introduced at the C-6 positions of a CD moiety by an acylhydrazone dynamic covalent bond, resulting in unique Janus amphiphilic glycopeptide dendrimers with precise and varied molecular structures. The kinds of hydrophilic parts of saccharides and hydrophobic parts of peptides were easily varied to prepare a series of amphiphilic Janus glycopeptide dendrimers. Intriguingly, these obtained amphiphilic glycopeptide dendrimers showcased very different self-assembly behaviors from the traditional amphiphilic linear block-copolymers and self-assembled into different glyco-nanostructures with controllable morphologies including glycospheres, worm-like micelles, and fibers depending upon the repeat unit ratio of saccharides and phenylalanine. Both glycodendrons and glycopeptide assemblies displayed strong and specific recognitions with C-type mannose-specific lectin. Moreover, these glycopeptide nanomaterials can encapsulate exemplary hydrophobic molecules such as Nile red (NR). The dye-loaded glycopeptide nanostructures showed a pH-controllable release behavior around the physiological and acidic tumor environment. Furthermore, cell experiments demonstrated that such glyco-nanostructures can further facilitate the functions of a model drug of the pyridone agent to reduce the expression of monocyte chemotactic protein-1 (MCP-1) and interleukin -1beta (IL-1ß) in the primary peritoneal macrophages via encapsulating drugs. Considering all the abovementioned advantages including unique and precise structures, bioactivity, targeting, and controllable cargo release, we believe that these findings can not only enrich the library of glycopeptides but also provide a new avenue to the fabrication of smart and structure-controllable glyco-nanomaterials which hold great potential biological applications such as targeted delivery and release of therapeutic and bioactive molecules.
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Dendrímeros , Nanoestructuras , Dendrímeros/química , Glicopéptidos/química , Micelas , Nanoestructuras/química , PolisacáridosRESUMEN
Polymeric nanoreactors in water fabricated by the self-assembly of amphiphilic copolymers have attracted much attention due to their good catalytic performance without using organic solvents. However, the disassembly and instability of relevant nanostructures often compromise their potential applicability. Herein, the preparation of 2,2,6,6-tetramethylpiperidine-1-oxyl (TEMPO)-containing nanoreactors by the self-assembly of amphiphilic bottlebrush copolymers has been demonstrated. First, a macromonomer having a norbornenyl polymerizable group was prepared by RAFT polymerization of hydrophobic and hydrophilic monomers. The macromonomer was further subjected to ring-opening metathesis polymerization to produce an amphiphilic bottlebrush copolymer. Further, TEMPO, as a catalyst, was introduced into the hydrophobic block through the activated ester strategy. Finally, TEMPO-functionalized polymeric nanoreactors were successfully obtained by self-assembly in water. The nanoreactors exhibited excellent catalytic activities in selective oxidation of alcohols in water. More importantly, the reaction kinetics showed that the turnover frequency is greatly increased compared to that of the similar nanoreactor prepared from liner copolymers under the same conditions. The outstanding catalytic activities of the nanoreactors from bottlebrush copolymers could be attributed to the more stable micellar structure using the substrate concentration effect. This work presents a new strategy to fabricate stable nanoreactors, paving the way for highly efficient organic reactions in aqueous solutions.
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The study of ion specificities of charged-neutral random copolymers is of great importance for understanding specific ion effects on natural macromolecules. In the present work, we have investigated the specific anion effects on the thermoresponsive behavior of poly([2-(methacryloyloxy)ethyl trimethylammonium chloride]-co-N-isopropylacrylamide) [P(METAC-co-NIPAM)] random copolymers. Our study demonstrates that the anion specificities of the P(METAC-co-NIPAM) copolymers are dependent on their chemical compositions. The specific anion effects on the copolymers with high mole fractions of poly(N-isopropylacrylamide) (PNIPAM) are similar to those on the PNIPAM homopolymer. As the mole fraction of PNIPAM decreases to a certain value, a V-shaped anion series can be observed in terms of the anion-specific cloud point temperature of the copolymer, as induced by the interplay between different anion-polymer interactions. Our study also suggests that both the direct and the indirect anion-polymer interactions contribute to the anion specificities of the copolymers. This work would improve our understanding of the relationship between the ion specificities and the ion-macromolecule interactions for naturally occurring macromolecules.
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Using dynamic polymers to achieve the morphology transformation of polymeric assemblies under different conditions is challenging. Herein, we reported diversiform shape transformation of multi-responsive polymer filaments, which were self-assembled by a new kind of amphiphilic block copolymer (PVEG-PVEA) possessing dynamic and reversible acylhydrazone bonds through reacting benzaldehyde-containing block copolymers poly(vinylbenzaldehyde)-b-poly(N-(4-vinylbenzyl)-N,N-diethylamine) (PVBA-PVEA) with acylhydrazine-modified oligoethylene glycol. It was found that the resulting amphiphilic and dynamic PVEG-PVEA was capable of hierarchically self-assembling into intriguing core-branched filaments in aqueous solution. Notably, the features of acylhydrazone bonds and PVEA block endow the filaments with multi-responsiveness including acid, base, and temperature, leading to the multiple morphological transformations under such stimuli. Moreover, the core-branched filaments would further transform into polymeric braided bundles driven by hydrogen-bonding interactions of amide bonds. It is noteworthy that both core-branched filaments and braided bundles made from polymers are quite rare. These diversiform polymeric assemblies and their morphological evolution were characterized by TEM, Cryo-TEM, SEM, and DLS. Finally, we used PVBA-PVEA as a platform to facilely prepare functional polymers, such as glycopolymers via the reaction of amino-containing sugars and aldehyde groups. The obtained glycopolymers self-assembled into glycofibers for the biomimicry of glycans via binding with lectins. These findings not only are conducive to understanding of the stimulated shape change process of dynamic polymeric assemblies in water but also provide a new method for the facile fabrication of smart and functional polymeric assemblies for different potential applications, such as biomimicry and targeted drug nanocarriers or delivery vehicles.
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Micelas , Polímeros , Sistemas de Liberación de MedicamentosRESUMEN
Nucleobase-functionalized covalent polymers are attracting great attention owing to their versatile structures, accessible architectures and robust properties. Although these materials are still inferior compared with DNA-based materials, they have demonstrated tremendous potential for more sophisticated applications in the biomedical field. In this review, we focus on recent advances concerning these materials. First, diverse synthetic strategies of nucleobase-functionalized polymers are introduced and summarized, emphasizing the accessible degree of polymerization and species of nucleobase functionalities. Template polymerization is highlighted as a novel and unique method for the synthesis of nucleobase-containing polymers. Various applications, such as drug and gene delivery carriers, supramolecular hydrogels and adhesives, and self-healing materials, are discussed. This review concludes with issues and challenges that are faced by this class of materials, in the hope of promoting further development of nucleobase-functionalized polymers for broader applications.
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Materiales Biocompatibles/química , Nucleósidos/química , Polímeros/química , Materiales Biocompatibles/síntesis química , Portadores de Fármacos/química , Silenciador del Gen , Técnicas de Transferencia de Gen , Hidrogeles/química , Polímeros/síntesis químicaRESUMEN
Herein we report the synthesis of a cellulose-grafted bottlebrush copolymer with nucleobases as hydrophobic moieties. Well-defined spherical micelles from this bottlebrush copolymer were fabricated via a solvent switch method. A morphological transition from spheres to worms was only observed to occur when a diblock copolymer with a complementary nucleobase functionality was introduced. Hydrophobic interaction is not capable of triggering the morphological transformation, and the diblock copolymer with the heterogeneous acrylamide nucleobase monomer can induce the morphological transition at higher A:T molar ratios, which might be caused by the weak H-bonding interaction. This supramolecular "grafting to" method enables the preparation of a series of nanoparticles with similar shapes and dimensions but distinct surface properties such as zeta potentials. Moreover, reversible morphological transitions between worm-like micelles and spheres can be achieved using a reversible collapsing and swelling of a thermoresponsive polymer. This work highlights that a supramolecular "grafting to" approach between complementary nucleobases can be utilized to tune morphologies and surface properties of nanoparticles.
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Adenina/química , Celulosa/química , Nanopartículas/química , Polímeros/química , Acrilamidas/química , Resinas Acrílicas/química , Enlace de Hidrógeno , Polímeros/síntesis química , Espectrofotometría Ultravioleta , Propiedades de Superficie , Timina/químicaRESUMEN
Understanding and controlling self-assembly processes at multiple length scales is vital if we are to design and create advanced materials. In particular, our ability to organise matter on the nanoscale has advanced considerably, but still lags far behind our skill in manipulating individual molecules. New tools allowing controlled nanoscale assembly are sorely needed, as well as the physical understanding of how they work. Here, we report such a method for the production of highly anisotropic nanoparticles with controlled dimensions based on a morphological transformation process (MORPH, for short) driven by the formation of supramolecular bonds. We present a minimal physical model for MORPH that suggests a general mechanism which is potentially applicable to a large number of polymer/nanoparticle systems. We envision MORPH becoming a valuable tool for controlling nanoscale self-assembly, and for the production of functional nanostructures for diverse applications.
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"Grafting to" polymeric nanostructures or surfaces is a simple and versatile approach to achieve functionalization. Herein, we describe the formation of mixed polymer-grafted nanoparticles through a supramolecular "grafting to" method that exploits multiple hydrogen-bonding interactions between the thymine (T)-containing cores of preformed micelles and the complementary nucleobase adenine (A) of added diblock copolymers. To demonstrate this new "grafting to" approach, mixed-corona polymeric nanoparticles with different sizes were prepared by the addition of a series of complementary diblock copolymers containing thermoresponsive poly(N-isopropylacrylamide) (PNIPAM) to a preformed micelle with a different coronal forming block, poly(4-acryloylmorpholine) (PNAM). PNIPAM chains were distributed throughout the corona and facilitated a fast and fully reversible size change of the resulting mixed-corona micelles upon heating. Through the introduction of an environmentally sensitive fluorophore, the reversible changes in nanoparticle size and coronal composition could be easily probed. Furthermore, preparation of mixed-corona micelles also enabled ligands, such as d-mannose, to be concealed and displayed on the micelle surface. This supramolecular "grafting to" approach provides a straightforward route to fabricate highly functionalized mixed polymeric nanostructures or surfaces with potential applications in targeted diagnosis or therapy and responsive surfaces.
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Weak polyelectrolytes have found extensive practical applications owing to their rich pH-responsive properties. In contrast, strong polyelectrolytes have long been regarded as pH-insensitive based on the well-established fact that the average degree of charging of strong polyelectrolyte chains is independent of pH. The possible applications of strong polyelectrolytes in smart materials have, thus, been severely limited. However, we demonstrate that almost all important properties of strong polyelectrolyte brushes (SPBs), such as chain conformation, hydration, stiffness, surface wettability, lubricity, adhesion, and protein adsorption are sensitive to pH. The pH response originates from the reorganization of the interchain hydrogen bond network between the grafted chains, triggered by the pH-mediated adsorption-desorption equilibrium of hydronium or hydroxide with the brushes. The reorganization process is firmly identified by advanced sum-frequency generation vibrational spectroscopy. Our findings not only provide a new understanding of the fundamental properties of SPBs but also uncover an extensive family of building blocks for constructing pH-responsive materials.
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Enlace de Hidrógeno , Concentración de Iones de Hidrógeno , Polielectrolitos/química , Polímeros/química , Resinas Acrílicas/química , Adsorción , Conformación Molecular , Proteínas/química , Tecnicas de Microbalanza del Cristal de Cuarzo , Propiedades de SuperficieRESUMEN
Amphiphilic nucleobase-containing block copolymers with poly(oligo(ethylene glycol) methyl ether methacrylate) as the hydrophilic block and nucleobase-containing blocks as the hydrophobic segments were successfully synthesized using RAFT polymerization and then self-assembled via solvent switch in aqueous solutions. Effects of the common solvent on the resultant morphologies of the adenine (A) and thymine (T) homopolymers, and A/T copolymer blocks and blends were investigated. These studies highlighted that depending on the identity of the common solvent, DMF or DMSO, spherical micelles or bicontinuous micelles were obtained. We propose that this is due to the presence of A-T interactions playing a key role in the morphology and stability of the resultant nanoparticles, which resulted in a distinct system compared to individual adenine or thymine polymers. Finally, the effects of annealing on the self-assemblies were explored. It was found that annealing could lead to better-defined spherical micelles and induce a morphology transition from bicontinuous micelles to onion-like vesicles, which was considered to occur due to a structural rearrangement of complementary nucleobase interactions resulting from the annealing process.
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Like natural enzymatic systems, our study has demonstrated that the activity of the polymeric organocatalysts can be modulated by ion-specific effects via the combination of anion-specific salting-in/out effects and anion-specific polarization of hydrogen bonding induced stabilization of the transition state.