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Graphical abstract The pH windows of vesicles formed by unsaturated fatty acids are successfully migrated to neutral environment, which shows great potential for the application in drug delivery system. Abstract Fatty acids, as anionic surfactants, can form different self-assembled structures in alkaline solutions. It has been reported that unsaturated fatty acids (UFAs) are more likely to form vesicles in this condition. Generally, fatty acid vesicles are formed near their respective pKa (8–9), which is far from the neutral range to which the life system fits. Furthermore, vesicles formed by UFAs are extremely sensitive to pH, which limit their application. To solve this problem, we added sodium dodecyl sulfate (SDS), an anionic surfactant, to the vesicles formed by C 18 UFAs to adjust the ionic effect in aqueous solution. Thereby, the formed pH windows of vesicles are migrated and expanded, which can be close to the pH range of physiological environment. Meanwhile, the vesicles formed by SDS-UFAs were determined by cryogenic transmission electron microscopy (cryo-TEM) and particle size analyzer to obtain nanocarriers with a particle size of 200–300 nm. Afterwards, the hemolysis, cytotoxicity, sustained release behavior and cellular uptake of drug-loaded nanocarriers were evaluated in vitro. This result can provide theoretical guidance for the application of drug-loaded vesicles in drug delivery system. [ABSTRACT FROM AUTHOR]

Abstract: This paper describes an interesting structure dependent thermo-reversible dissolution of organic molecules in the presence of β-cyclodextrin (β-CD) in N, N-dimethyllformamide (DMF). β-CD could influence the solubility of dissolved organic molecules, resulting in the precipitation of organic molecule–β-CD complex from the original transparent solution as the temperature is increasing, while the precipitate will be dissolved again upon cooling. Different organic molecule–β-CD complex precipitates corresponded to different turbid temperatures (T t ). No precipitates were observed solely for either organic molecules or β-CD in DMF when the temperature increased, indicating the structure dependent recognition of β-CD to organic molecules. This molecular recognition behavior had been successfully applied in the separation of xylene isomers in preparative scale. [Copyright &y& Elsevier]

Abstract: Methylated β-cyclodextrin and a class of phthalate esters were found to be able to form “supramolecular amphiphiles” with double-chains in aqueous solution and could further assemble into stable vesicles under variable conditions. The vesicles were fully characterized by transmission electron microscopy (TEM), scanning electron microscopy (SEM), dynamic light scattering (DLS) and Cryo-transmission electron microscopy (Cryo-TEM). The mechanism of the vesicle-formation was suggested based on the UV–vis spectrum, 1H NMR, 2D NMR NOESY, FT-IR spectrum and X-ray diffraction (XRD) results and further simulated by molecular dynamic simulation. The vesicles’ responses to the stimuli were also studied. [Copyright &y& Elsevier]

The self-assembly properties of long-chain C 18 fatty acids salts have good application in the field of environmental protection, drug control relieve, renewable energy and so on. Their degree of unsaturation is varied from saturated, monounsaturated to polyunsaturated fatty acids, which influence their self-assembly behaviors. Moreover, different external stimuli can also affect different self-assembly behaviors. In this work, three different fatty acids (stearic acid, C 18:0 ; oleic acid, C 18:1 ; linoleic acid, C 18:2) were chosen as the building blocks to self-assemble with arginine, a basic amino acid. The phase behaviors of ion-pairing systems affected by pH, temperature and solvent were investigated based on diagrams in more detail. The rich phase transition was observed through the characterization by cryogenic-transmission electron microscopy (cryo-TEM), polarizing microscopy, particle size analysis and rheological properties. We hope that the phase transition (self-assembly behaviors) controlled by these external conditions may provide a good guide for many related fields. [ABSTRACT FROM AUTHOR]

Nano-photothermal platforms based on the second near-infrared (NIR-II) spectral window attract considerable attention in antimicrobial treatment for the negligible bacterial resistance and deeper penetration in biological tissues. Nevertheless, combining NIR-II photothermal therapy (PTT) with diversified therapeutic modalities for synergistic and enhanced therapeutic efficacy remains challenging for clinical trials. Herein, we report a bacteria-targeting nanozyme based on hollow-structured Cu 2 MoS 4 (PV@HCMS) for performing synergistic therapy of NIR-II (1064 nm) PTT and chemodynamic therapy (CDT). PV@HCMS with superb photothermal conversion efficiency and peroxidase-like (POD-like) catalytic performance could generate highly cytotoxic •OH via NIR-II-enhanced Fenton-like reactions. Polyethyleneimine-vancomycin (PV) modified copolymers conjugated via amide bonds endows PV@HCMS with robust bacterial eradication property through a dual-targeting approach, in turn favoring the synergistic PTT-CDT. Both in vitro and in vivo antimicrobial evaluation show satisfactory bactericidal efficacy and biocompatibility. Of special note, PV@HCMS is further incorporated into the thermosensitive hydrogel poloxamer F127 to form a composite dressing (PHF) with outstanding skin regeneration function and antimicrobial activity for the comprehensive treatment of burn infection. This study proposes a multi-modal collaborative therapy based on nanozymes for enhanced anti-infective efficacy in different scenarios through the optimal design of both composition and morphology. [Display omitted] [ABSTRACT FROM AUTHOR]

Agricultural plastic film (APF) is extensively used in modern agriculture. However, to the best of our knowledge, the self-cleaning property and light transmittance of APF are still the main factors affecting crop yield at present. To solve these problems, for the first time, we developed polyethylene-based dust-proof composite APF with multi-scale micro-nano structure and light conversion performance. By combining the carbon dots (CDs) and hydrophobic silica nanoparticles (FSi-SiO 2) with organically modified montmorillonite (OMMT), composite materials with multi-scale micro-nano structure and low surface energy (SFE) were constructed (FSi-SiO 2 /CDs@OMMT). After blending with linear low-density polyethylene (LLDPE, PE), a self-cleaning dust-proof APF with "lotus-effect" was synthesized (PE/FSi-SiO 2 /CDs@OMMT). The PE/FSi-SiO 2 /CDs@OMMT exhibited excellent hydrophobic property, which had a water contact angle (WCA) of 108.9°. The results of the mechanical properties tests showed that the horizontal and portrait tensile strength of PE/FSi-SiO 2 /CDs@OMMT improved from 25.08 and 27.41 MPa to 33.14 and 42.21 MPa and that the horizontal and portrait elongation at break improved from 273.53 % and 380.23–369.43 % and 480.73 %, respectively. In addition, the anti-fouling and dust-proof performance were studied, and the results showed that the anti-fouling rate and dust removal efficiency of PE/FSi-SiO 2 /CDs@OMMT were reached to 99.84 % and 99.58 %, respectively. Additionally, PE/FSi-SiO 2 /CDs@OMMT also possessed excellent thermal stability, anti-algae and anti-bacterial adhesion properties, and light conversion performance. This work could provide a facile approach and strategy to fabricate functional APF for agricultural application. [Display omitted] • The preparation raw materials and method of PE/FSi-SiO 2 /CDs@OMMT are inexpensive and facile. • PE/FSi-SiO 2 /CDs@OMMT possess blue fluorescence effect and multi-scale micro-nano structure. • PE/FSi-SiO 2 /CDs@OMMT exhibit excellent hydrophobic property, mechanical property, thermal stability, anti-fouling and dust-proof performance, anti-algae and anti-bacterial adhesion properties. • PE/FSi-SiO 2 /CDs@OMMT exhibit excellent light conversion performance. [ABSTRACT FROM AUTHOR]

Exploring a facile, low-cost, scalable, and environmentally friendly fluorescent superhydrophobic material is urgent and significant for the further development of superhydrophobic materials. In this work, we developed two series of superhydrophobic materials with different scale hierarchical structures. 0.5FSi-SiO 2 @MMT possessed a dual-scale hierarchical structure and showed a WCA of 155.62 ± 1° and a WSA of 4.8 ± 0.2°. On this basis, by introducing CDs, the denser multi-scale hierarchical structure of FSi-SiO 2 /0.1CDs@OMMT was achieved resulting in a higher WCA of 169.22 ± 2° and a lower WSA of 2.3 ± 0.2°. FSi-SiO 2 /0.1CDs@OMMT possessed a fluorescence property derived from the doping of biomass carbon quantum dots prepared from banana peels and displayed an emission band located at 430 nm. In addition, FSi-SiO 2 /0.1CDs@OMMT also exhibited good heat and dispersion stability. Interestingly, chemical resistance was significantly improved after introducing CDs. It is anticipated that this work will provide a facile and general approach with the industrial potential to fabricate superhydrophobic materials with hierarchical micro-nano structures and blue fluorescence for self-cleaning and light conversion applications. [Display omitted] [ABSTRACT FROM AUTHOR]

Abstract: Vesicles constructed by supramolecular amphiphiles are considered as more promising stimuli-responsive vehicles for carrying and delivering targeted molecules. In this research, novel supramolecular amphiphiles are directly assembled from UR-144, a general neuropathic drug, and a class of mono-diaminoalkane substituted β-cyclodextrins. In the aqueous solution, the supramolecular amphiphiles can assemble into vesicular particles, which were characterized in detail by transmission electron microscopy (TEM), atomic force microscopy (AFM), scanning electron microscopy (SEM) and dynamic light scattering (DLS). The mechanism was also suggested based on the NMR, Fourier transform infrared spectroscopy (FT-IR) and X-ray diffraction (XRD) experimental results. The vesicular particles tend to be damaged upon the addition of Cu2+ and meanwhile release UR-144. [Copyright &y& Elsevier]

Abstract: Micro-aggregates based on inclusion complexes between methyl orange (MO) and cyclodextrins (CDs) were investigated for the first time. The mixture of MO and γ-hydroxybutyric-β-cyclodextrin (γ-HB-β-CD) in water was observed to aggregate into vesicle-like particles by transmission electron microscopy (TEM), laser-confocal scanning microscopy (LCSM) and dynamic light scattering (DLS). Fluorescence measurements and NMR confirmed the existence of inclusion complexes between MO and γ-HB-β-CD. The formation mechanism and pH-responsive properties of the vesicle-like particles made by MO·γ-HB-β-CD have been investigated and discussed. This work is important reference for further investigating the vesicles and particles prepared based on host–guest interactions, and it is guide to understand the behavior of MO·β-CD complexes in fluorescent probes and bio-mimicking, etc. [Copyright &y& Elsevier]

In recent years, stimuli-responsive controlled-release pesticide formulations have drawn extensive as they show huge potential in the practical application of agriculture. Herein, a multifunctional composite nanocarrier was prepared by our group, Poly(N-isopropylacrylamide) modified graphene oxide (PNIPAm-GO), this is a temperature-responsive release pesticide formulation that can regulate pesticide release based on the temperature change. Lambda-cyhalothrin (LC) was loaded on PNIPAm-GO nanocomposite carrier via a simple physisorption process and LC@PNIPAm-GO exhibited temperature-responsive controlled release performance leading to release of LC at a specified temperature and extended its persisted release time. In addition, the LC@PNIPAm-GO controlled-release pesticide formulations showed both good water solubility and dispersion stability while its anti-UV property. Furthermore, we also assessed the biological safety of LC@PNIPAm-GO and proved that PNIPAm-GO is non-toxic. The study of this temperature-responsive pesticide formulation has promoted the development of intelligent pesticide formulations to great extent. [ABSTRACT FROM AUTHOR]

A series of chemical reactions were designed to form covalent bonds between polymers and GO nanosheets according to the synthetic route above. GE and GEA gained by in-situ RAFT polymerization on GO surface improve the dispersity of graphene oxide sheets in cement, which reinforce cement via regulating hydration process. Graphene oxide (GO) nanosheets own a large specific surface area and excellent mechanical properties. GO sheets can be dispersed in water to form nano dispersoid, and are easy to composite with cement-based materials. However, the dispersity of GO in alkaline cement slurry is inferior, which causes severe agglomeration, so that the enhancement effect of GO cannot be fully utilized. In this paper, GO-g-PPOE (GE) and GO-g-PPOE- b -PAA (GEA) were synthesized via RAFT polymerization on GO surface. The growth models of poly(poly(ethylene glycol) methyl ether methacrylate) (PPOE) and poly(poly(ethylene glycol) methyl ether methacrylate) -co- acrylic acid) (poly(POE-co-AA)) from GO surface were predicted by TEM and SEM. The result of Zeta potential proved that both GE and GEA effectively improved the dispersity of graphene oxide in cement pore solution. Due to the improvement of dispersity and the adsorption of metal ions in cement paste, GE and GEA promoted cement hydration, thereby reinforcing cement composites. [ABSTRACT FROM AUTHOR]