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Uncontrolled bleeding is one of the most important causes threatening human health, but quick hemostasis remains a challenge. We prepared porous cryogels with poly β-cyclodextrin (Pβ-CD) and quaternary ammoniated chitosan (QCs). Pβ-CD acts as a "water-grabbing agent" to assist QCs' ability to absorb and concentrate blood rapidly. The rat-tail amputation model and liver injury model exhibited that cryogels had excellent hemostatic performance. Moreover, cryogels showed good antibacterial activity and biocompatibility. Therefore, these cryogels can be used as potential hemostatic materials.

Tear resistance is of vital importance in the fabrication and application of synthetic soft materials. However, the paradox of simultaneously improving the tearing energy and elasticity remains a huge challenge for conventional approaches. Here, inspired by the skin, we successfully constructed an extraordinary tear-resistant, superelastic elastomer by the introduction of nanosized polycyclodextrin into the elastomer network to form a slidable interpenetrate double network structure. The tearing energy of the SDEP elastomer is up to 274 KJ/m

High strength and ductility materials are in demand for various modern applications. In order to surmount the inherent trade-off between toughness and stiffness for most elastomers, we developed a strategy which let two polymer networks form an interpenetrated structure through introducing slip-rings by a very simple one-step synthesis method. The synergistic effect of the slip-rings and the double network structure make the resulting materials (SRDN elastomers) both tough and stiff. The fracture stress is up to 11 MPa. The maximum fracture strain is 1600%. Furthermore, the SRDN elastomers show good tear resistance and fracture energy of up to 66.3 kJ m−2 and 79.3 MJ m−3, respectively. In addition, the SRDN elastomers show self-healing properties similar to those of the PHEA elastomer, since the slip effect imparts good chain mobility to the material. This research provides a facile approach to fabricate super tough and stiff elastomers with self-healing ability.

Tough self-healing elastomers with excellent comprehensive performance are extremely demanding and fascinating for future product development, such as wearable devices and robots. However, the defo...

Efficient, flexible and self-healing electromagnetic interference (EMI) shielding materials are highly desirable and valuable for electromagnetic shielding industry. Furthermore, in order to achieve a commercial-grade EMI shielding effectiveness, a large amount of filler is required. Here, a kind of self-healing EMI shielding fabric was fabricated by preparing aligned carbon nanotube-poly (2-hydroxyethyl methacrylate) (CNT-PHEMA) non-woven fabric through magnetic-field-assisted electrospinning and cross-stacking aligned fabric layers. The unique aligned CNT stacking and porous structure enable that the materials can effectively absorbing EMI even at very low CNT loading amount (0.17 wt%). The host-guest interaction between β-cyclodextrin (β-CD) and adamantane (Ad) moieties not only made the fabric can adhere together automatically but also self-heal the scratch under 100% humidity environment. After the healing, the EMI shielding property can be restored 90.86 ± 3.90%.

The adsorption of CO2 by conventional liquid alkanolamine adsorbents does not meet the requirements for green-friendly development in industrial applications. In this work, we constructed NH2-β-CD-MOF for the first time through the amino-functionalization of the lowest-priced, readily available, and biocompatible β-CD. Subsequently, the samples were characterized by single-crystal X-ray diffraction, powder X-ray diffraction, scanning electron microscopy, differential scanning calorimetry, thermogravimetric analysis, elemental analysis, and N2 adsorption/desorption. The CO2 adsorption capacity of NH2-β-CD-MOF was found to be 12.3 cm3/g, which is 10 times that of β-CD-MOF. In addition, NH2-β-CD-MOF has outstanding selective adsorption of CO2/N2 (947.52) compared with the reported materials. The adsorption mechanism of CO2 was analyzed by X-ray photoelectron spectroscopy and Fourier transform infrared spectroscopy. Furthermore, we have found that NH2-β-CD-MOF has better water stability relative to β-CD-MOF a...

An efficient, mild, and green method was developed for the synthesis of indeno[1,2-b]quinoxaline derivatives via o-phenylenediamine (OPD) and 2-indanone derivatives utilizing β-cyclodextrin (β-CD) as the supramolecular catalyst. The reaction can be carried out in water and in a solid state at room temperature. β-CD can also catalyze the reaction of indan-1,2-dione with OPD with a high degree of efficiency. Compared to the reported methods, this procedure is milder, simpler, and less toxic, making it an eco-friendly alternative. In addition, the β-CD can be recovered and reused without the loss of activity.

Materials that can undergo shape deformation have potential applications in biomedical field, yet it has always been a challenge to pattern hydrogels and accurately program target three-dimensional (3D) shapes through a simple method. Here, we develop a facile method that permits fabrication of inhomogeneous hydrogels, which can reversibly deform from planar sheet to 3D shape in response to multistimuli, such as pH values, SLDC (solutions with lower dielectric constant), and SBF (simulated body fluid). By printing NaOH solution ink on classic PAAm hydrogel sheet, the amide side groups of PAAm hydrolyzed to acrylate. The swelling mismatch of the printed and unprinted areas generates internal stress to activate hydrogel deformation. Adjusting concentration of NaOH solution or number of times of printing, it is convenient to introduce in-plane and through-thickness gradient distribution to hydrogel sheet. The inkjet printing process is easily controlled by computer, enabling the direct printing of batched an...

Increasing resistance to humid environments is a major challenge for the application of γ-CD-K-MOF (a green MOF) in real-world utilisation. γ-CD-K-MOF–H2S with enhanced moisture tolerance was obtained by simply treating MOF with H2S gas. XPS, Raman and TGA characterizations indicated that the H2S molecules coordinated with the metal centers in the framework. H2S acting as a newly available water adsorption potential well near the potassium centers protects the metal–ligand coordination bond from attack by water molecules and thus improves the moisture stability of MOF. After 7 days exposure in 60% relative humidity, γ-CD-K-MOF–H2S retained its crystal structure and morphology, while γ-CD-K-MOF had nearly collapsed. In addition, the formaldehyde uptake tests indicated that γ-CD-K-MOF retain their permanent porosity after interaction with H2S. This simple and facile one-step strategy would open a new avenue for preparation of moisture stable MOFs for practical applications.

Mixed matrix membranes (MMMs) for CO2 separation have overcome the trade-off between gas permeability and gas selectivity to some extent. However, most MMMs still are prepared in lab- and pilot-scales since the permeability and selectivity of CO2 are not good enough to reach the economically available requirements. Moreover, the fabrication of few MMMs with good separation performance is time-consuming or need harsh conditions. In this study, a novel MOF-based composite membrane (PAN-γ-CD-MOF-PU membrane) was successfully fabricated by a facile and fast spin-coating method. In the two-step coating process, we applied a uniform selective layer of γ-cyclodextrin-MOF (γ-CD-MOF) on porous polyacrylonitrile and then coated a layer of polyurethane on the γ-CD-MOF layer. The entire membrane formation process was about 30 s. The formation of a unique γ-CD-MOF layer greatly improved the separation ability of CO2 (the CO2 permeability is 70.97 barrers; the selectivity to CO2/N2 and CO2/O2 are 253.46 and 154.28, respectively). The gas separation performance can exceed the Robeson upper limit obviously and the selectivity is better than other MOF-based composite membranes. In addition, the PAN-γ-CD-MOF-PU membrane is strong and flexible. Therefore, the PAN-γ-CD-MOF-PU membrane developed in this study has great potential in large-scale industrial separation of CO2.

A novel approach has been developed to prepare the magnetic micelles. Polyethylene glycol (PEG) and poly(N-isopropylacrylamide) (PNIPAM) are firstly attached on the surface of the magnetic nanoparticle via the host–guest inclusion between ferrocene groups (Fc) and β-cyclodextrin (β-CD). Then the resulting MNPs became amphiphilic in water above the LCST of PNIPAM and self-assembled into magnetomicelles with a size of 250 nm. These hybrid micelles show high loading capacity for anticancer drug (DOX) and high saturation magnetization simultaneously. Furthermore, these micelles could disassemble under the effects of oxidant or temperature, providing an opportunity to fine-tune the release properties of the encapsulated drug in response to temperature, H2O2 or pH independently, or a combined effect of multiple stimuli. Taking other advantages of magnetic carriers, such as high sensitivity to the external magnetic field, contrast effect to magnetic resonance, and magnetic hyperthermia, the micelles developed by this study show great potential application in cancer treatment.

Fibers with good flame retardant (FR) and smoke suppression performances are highly desirable for the purpose of eliminating fire hazard. This study developed a novel FR fiber by wet-spinning poly (vinyl alcohol)/&beta, cyclodextrin (PVA/&beta, CD) composite fiber and crosslinking it with hexamethylene diisocyanate (HDI). &beta, CDs showed good compatibility with PVA matrix, and the resulting PVA/CD/HDI fibers showed mechanical strength at the same level as natural cotton fiber. The PVA/CD/HDI fibers also showed excellent flame retardance (the LOI value of PVA/CD/HDI could reach 41.7%, and their peak of heat release (PHRR) could be reduced by up to 77.7% by neat PVA), and super-smoke suppression (the value of total smoke production (TSP) was only 28.6% compared to PVA). These dramatic reductions of fire hazard were ascribed to the char formation of &beta, CD and crosslinking structure of PVA/CD/HDI, which formed a compact char layer during combustion, thus preventing heat transmission and smoke release.

The adsorption of CO

Porous materials have attracted significant attention because of their rising applications in many fields. Cyclodextrins (CDs) are suitable building units in the fabrication of porous materials owing to their intrinsic nanoporous structure, easy modification, and biocompatibility, which may result in the formation of CD-based organic frameworks (including cyclodextrin metal-organic frameworks (CD-MOFs) and cyclodextrin covalent organic frameworks (CD-COFs)), and CD-based polymer hybrid porous materials. This review focuses on the recent progress in the fabrication and applications of CD-based porous materials with novel structures and functionalities.

A kind of metal-organic framework made from γ-cyclodextrin (γ-CD) and potassium ions were explored as excellent formaldehyde (HCHO) absorbents. The adsorption capacity and speed of γ-CD-MOF-K are both about 9 times higher than those of activated carbon, which are attributed to the porous structure and synergistic effect of hydrogen bonding and host-guest interactions.

Adsorption is used extensively to deal with increasingly serious water pollution. In this paper, beta-cyclodextrin-graphene oxide aerogel microspheres (CD-GAM) with 3D porous structure was prepared by electrospraying combining with freeze-casting and sequently mild self-assembly. Owing to the integration of graphene oxide (GO) and beta-cyclodextrin (β-CD), the CD-GAMs exhibit excellent broad-spectrum adsorption capabilities for dyes and organic micropollutants, including anionic dyes of methylene blue (439 mg/g) and Rhodamine B (388 mg/g), cationic dyes of acid red 87 (234 mg/g) and methyl orange (167 mg/g), organic micropollutants aromatic model compound of carcinogen 2,4-dichlorophenol (17 mg/g), pharmaceuticals of propranolol hydrochloride (49 mg/g), contraceptive ethynyl estradiol (19 mg/g) and plastic components bisphenol A (38 mg/g). The adsorption capacity of CD-GAM for most pollutants reach equilibrium within 10 min. In addition, the CD-GAM maintained stable regenerative adsorption capacity more than 80 % in five cycles. The broad-spectrum adsorbent CD-GAM is an ideal choice for removing complex and diverse pollutants from wastewater.

Shape memory polymers (SMPs), with the capability to change from one or more temporary shapes to predetermined shapes in response to an external stimulus, have attracted much interest from both academia and industries. When introducing supramolecular interactions that have been featured as dynamic and reversible into the design of novel SMPs, intriguing and unique functionalities have been engendered and thereby broaden the potential applications of the SMPs to new territories. In this review, we summarize recent progress made in SMPs based on supramolecular interactions, provide insight into the material design and shape memory mechanism, elucidate and evaluate their properties and performance, and point out opportunities and applications of SMPs.

A pH and glutathione (GSH) dual bio-relevant triggered supramolecular system is constructed through the non-covalent host–guest interactions between the adamantane (ADA) on camptothecin (CPT) and β-cyclodextrin (β-CD) on the side chain of the backbone of hyaluronic acid (HA). The obtained non-covalent supramolecular β-CD-g-OX-HA/ADA-CPT complex could further self-assemble into a stable uniform sphere micellar structure with constant drug loading content in the extracellular environment but is cleaved in the cytosol of the cancer cells due to the acidic environment and the presence of a high concentration of GSH, resulting in a synergistic-fast pH and GSH triggered drug releasing behavior. The cytotoxicity of the supramolecular β-CD-g-OX-HA/ADA-CPT micelles was investigated using Hep G2 cancer cells by MTT assays, which displayed that supramolecular β-CD-g-OX-HA/ADA-CPT micelles had exhibited enhanced cellular proliferation inhibition against Hep G2 cancer cells compared to the free CPT, while the β-CD-g-OX-HA had good cell compatibility. In vivo studies of the β-CD-g-OX-HA/ADA-CPT micelles showed a higher in vivo efficacy without side effects and also confirmed the compatibility of the β-CD-g-OX-HA. It is anticipated that this supramolecular complex will give the possibility to fabricate new types of bio-relevant triggered nanocarriers for cancer therapy.

A new type of chiral magnetic nano-particles was prepared via covalently linked magnetic nano-particles (Fe3O4) and heptakis (6-O-triisopropylsilyl)-β-cyclodextrin (6-TIPS-β-CD). The resulting selectors (TIPS-β-CD-MNPs) combined the high magnetic property Fe3O4 and efficient chiral recognition ability of 6-TIPS-β-CD. The enantioselectivity of TIPS-β-CD-MNPs towards 1-(1-naphthyl) ethylamine was six times higher than that of parent β-CD modified Fe3O4 particles.

Self-healing materials (SHMs) have been a research hot topic in recent years owing to their greatly improved longevity and safety in practical applications. Recently, research on SHMs has gradually expanded from structural materials to functional materials. Functional materials with self-healing properties (FMSH) require simultaneous repairing not only of the mechanical properties but of the functionalities from damaged cracks or wounds. It is more challenging to introduce both self-healing properties and a particular functionality to materials owing to the difficulties of preparing the materials and their more complex healing mechanism. Herein, we summarize the recent progress that has been made in FMSH, put forward insights from the perspectives of material preparation and healing mechanisms and highlight future developments for FMSH.

Increasing resistance to humid environments is a major challenge for the application of γ-CD-K-MOF (a green MOF) in real-world utilisation. γ-CD-K-MOF-H

Light-, pH- and thermal-responsive hydrogels were prepared by introducing dansyl-aggregations and azo-cyclodextrin inclusion complexes as switches. The resulting material showed dual shape memory behavior in response to light, pH or temperature, respectively, and exhibits the triple-shape memory effect in response to light and pH sequentially.

Airborne particulate matter (PM) pollution has become a serious environmental problem. Thus, there is a need for the development of air filters with satisfactory overall performance. In this paper, we develop a kind of β-cyclodextrin (β-CD) based air filter with high strength, which has not only high filtration efficiency (about 99%) but also good air permeability (the pressure drop is only 45Pa). Especially after long-term application, the pression drop of β-cyclodextrin based was less than half of the commercial air-filter. Additionally, the material can capture the toxic gasous chemicals (e.g. formaldehyde and SO2). The introduction of β-CD is supposed to be the key factor for improvement of air filter.

Inspired by the functions of leeches, for the first time homogeneous materials integrating hydrogels and elastomers were achieved by free radical polymerization. 2-Methoxyethyl acrylate (MEA) was used as elastomer monomer and Pluronics functionalized with vinyl groups acted as cross-linkers to impart the hydrogel property to the materials. The resulting Pluronic/PMEA gels possess a swelling ratio of about 210% and good water-retaining ability. Compression tests of Pluronic/PMEA gels at swelling equilibrium state show a stress up to 1.6 MPa under 85% strain. The gels act as elastomer after dehydration. Uniaxial tensile fracture stress and the elongation reached 1200 kPa and 500%, respectively, and compression stress was above 22 MPa. Furthermore, the Pluronic/PMEA gels also show self-healing properties. Owing to the excellent mechanical performance in both wet and dry conditions, this hydrogel-elastomer integrated material may have potential applications in tissue engineering, soft robotics, and biomedical devices.

The research of hydrogels has been increasingly focused on designing an effective energy dissipation structure in recent years. Here, we report a kind of novel supramolecular cross-linker, which was formed by self-assembling amphiphilic block copolymers with guest groups at the end and vinyl-functionalized cyclodextrin (CD) through host–guest interaction. These cross-linkers could dissipate energy effectively since they combined multiple sacrificial mechanisms across multiscales through physical interactions. The resulted hydrogel shows distinguishing mechanical properties (fracture toughness of 2.68 ± 0.69 MJ/m3, tension strength of up to 475 kPa, uniaxial stretch over 2100%), remarkable fatigue resistance, and thermal- and light-responsive behaviors.

Healable, electrically conductive materials are highly desirable and valuable for the development of various modern electronics. But the preparation of a material combining good mechanical elasticity, functional properties, and intrinsic self-healing ability remains a great challenge. Here, we design composites by connecting a polymer network and single-walled carbon nanotubes (SWCNTs) through host-guest interactions. The resulting materials show bulk electrical conductivity, proximity sensitivity, humidity sensitivity and are able to self-heal without external stimulus under ambient conditions rapidly. Furthermore, they also possess elasticity comparable to commercial rubbers.

Two end-decorated homopolymers, methoxy polyethylene glycol-ferrocene (mPEG-Fc) and poly(N-isopropylacrylamide)-β-cyclodextrin (PNIPAM-β-CD), were further orthogonally self-assembled into stable micelles in aqueous solution by controlling the temperature of the solution via terminal host–guest interactions. Because of the H2O2 cleavable CD/Fc connection and thermoresponsive PNIPAM, an H2O2 and thermo dual-controlled drug release based on this system was also achieved. Interestingly, the cytotoxicity evaluation of mPEG-Fc/PNIPAM-β-CD indicated good biocompatibility. Compared with free doxorubicin, the doxorubicin-loaded supramolecular micelles exhibited equal cellular proliferation inhibition toward A549 cells. This supramolecular complex is thus anticipated to serve as a promising new type of alternative drug-delivery system.

This study reported a smart, easy to apply, flexible and green strategy for obtaining a biomimic micro-nanostructures. 1-Mercapto-12-( p -nitrophenoxy) dodecane (MPND) and n -dodecanethiol were used to form low surface energy film on a silver mesodendritic structure coated zinc substrate. Scanning electron microscope (SEM) and X-ray photoelectron spectroscopy (XPS) were used to characterize surface morphology and mesocrystal structures. Noncovalently linked sodium nonanoyloxy benzene sulfonate (NOBS) was used to form “lipid-like bilayers” on the surface, making it possible for the surface to switch its surface wettability reversibly. The water contact angle (CA) on the constructed surface varies from 168 ± 2° (before processed by NOBS) to 55 ± 2° (after processed by NOBS). This phenomenon can be explained by the formation and disruption of “lipid-like bilayers” to affect the wettability of the surface. This work is of great scientific interests and may provide insights into the design of novel functional devices that are relevant to surface wettability, such as microfluidic devices and sensors.

Self-assembly of stimuli-responsive polymeric nanoparticles have attracted great attention in recent years due to their prospective biological applications. This paper developed a novel pH-sensitive amphiphilic dendritic polyrotaxane drug-polymer conjugate by covalently linking doxorubicin (DOX) and dendritic polyrotaxane via a pH-responsible hydrazone bond with 1.84 wt% (weight percent) of DOX. The drug-polymer conjugate was amphiphilic and could be self-assembled to micelles (PR-g-DOX micelles) in an aqueous solution. The globular morphology and compact micelles with a diameter of around 110 nm were observed by SEM and TEM. Moreover, the micelles showed a significantly faster DOX release at mildly acidic pH of 6.0 and 5.0 and almost no burst release at the physiological pH of 7.4. Notably, it was confirmed that this micelle could efficiently deliver DOX to the nuclei of the tumor cells, which led to a much greater cytotoxic effects in the A549 cancer cells than the parent DOX. In vivo results revealed better drug tolerability of PR-g-DOX micelles and a higher in vivo efficacy without any increase in the toxicity of the PR-g-DOX micelles. Furthermore, the maximum tolerated dose (MTD) results showed that PR-g-DOX micelles showed an excellent safety profile with a two-fold higher MTD (10 mg kg−1 DOX) than that of free DOX (5 mg kg−1 DOX). We are convinced that the PR-g-DOX micelle has tremendous potentials for targeted cancer therapy.

A self-healable conductive composite is developed by combining the small molecules and nanotubes through host-guest interactions. This material shows uniform conductivity, microwave absorption and humidity sensing properties, and can be rapidly healed to over 90% electrical and mechanical properties with the aid of water multiple times. In addition, the produced material is also remouldable and recyclable.

A dual redox and biorelevant triggered supramolecular system is developed through noncovalent supramolecular inclusion interactions between the ferrocene (Fc) modified on camptothecin (CPT) and β-cyclodextrin (β-CD) at the end of methoxy polyethylene glycol (mPEG). With these two segments, a stable noncovalent supramolecular structure, i.e., mPEG-β-CD/Fc-CPT, can be formed, and then self-assembled into micellar structures in water. Interestingly, these supramolecular micelles showed uniform sphere structure, high and constant drug loading content, hyper-fast redox-responsive drug release, and exhibited equal cellular proliferation inhibition toward A549 cancer cells. The cytotoxicity evaluation of mPEG-β-CD also indicated good biocompatibility. In vivo results revealed the mPEG-β-CD/Fc-CPT nanoparticles had higher in vivo efficacy without side effects. It is anticipated this supramolecular complex may serve as a new kind of promising alternative for drug delivery systems.