摘要：An alkaline isolation method was applied to extract polysaccharide from residues of peanut oil processing while retaining high protein content, in order to enhance the emulsifying ability of these materials. The obtained complexes (PECs) containing protein (13–18%, dry basis) were named as PEC8.0, PEC10.0 and PEC12.0 according to extraction pH values. The protein content of PECs increased with increasing extraction pH value, thereby the hydrophobicity was improved. Additionally, as extraction pH value increased to 10.0, the protein of PECs covalently bonded to polysaccharide and polysaccharide conformation unfolded simultaneously, thus particle size was enlarged. Furthermore, the increasing concentration of PECs further induced the formation of large complex particles. Then, they were used to stabilize the Pickering emulsions with oil fractions (φ) of 0.4–0.7. The emulsions stability especially the gel structure was maintained by the interactions of large particles adsorbed in the interface and those in the continuous phase. Stability analysis indicated the emulsifying capacity of PEC10.0 and PEC12.0 was superior to that of PEC8.0, due to difference of their particle properties. This suggested the promoting effect of alkali in preparation of polysaccharide-protein complex as good Pickering stabilizer.
摘要：It is important for antitumor drugs to accumulate at the tumor site and penetrate deeply to play a role in treatment. However, it is difficult for the drugs to reach the destination on account of the complex tumor microenvironment such as elevated tumor interstitial fluid pressure (IFP) and solid stress. Here, we report a type of nanocarrier composed entirely of Camellia oleifera protein (COP), which could lower tumor IFP and solid stress. Its physicochemical properties, cellular uptake, in vitro cytotoxicity and tumor perfusion, biodistribution, and in vivo antitumor efficiency were evaluated. It was found that COP NPs had good cellular uptake ability and cytocompatibility. When loading doxorubicin, COP NPs showed an in vitro concentration-dependent cytotoxicity. Importantly, the tumor IFP and solid stress were greatly reduced after injecting COP NPs into
摘要：The objective of this work is to fabricate zein/fucoidan composite nanoparticles for the delivery of pterostilbene, a hydrophobic nutraceutical with diverse beneficial biological activities. Pterostilbene-encapsulated zein/fucoidan composite nanoparticles were prepared using an anti-solvent precipitation method. The fucoidan levels affected the physicochemical properties of the composite nanoparticles. When the zein to fucoidan mass ratio was 10:1, 5:1, 2:1, or 1:1, the prepared zein/fucoidan nanoparticles were stable, and these nanoparticles showed higher pterostilbene encapsulation efficiency than did zein nanoparticles. Fucoidan-stabilized zein nanoparticles exhibited globular structure with average diameters of 120–150 nm. Fourier-transform infrared spectroscopy, X-ray diffraction, and fluorescence spectrum analysis confirmed that the formation of composite nanoparticles was mainly driven by electrostatic, hydrogen-bonding, and hydrophobic interactions between pterostilbene, zein, and fucoidan. Furthermore, the photochemical stability of pterostilbene encapsulated in zein/fucoidan nanoparticles was markedly better than that of pterostilbene loaded in zein nanoparticles or unencapsulated pterostilbene. Zein/fucoidan nanoparticles provided a better controlled release of pterostilbene than did zein nanoparticles under simulated gastrointestinal conditions. Moreover, the cytotoxicity assay demonstrated that zein/fucoidan nanoparticles were nontoxic to Caco-2, HK-2, and L-02 cells. Based on our results, the zein/fucoidan nanoparticles may be a promising delivery carrier for the encapsulation, protection, and release of pterostilbene.
摘要：The effect of the hexadecyltrimethylammonium bromide concentration in the silica sol, which is used to obtain antireflection coatings over silicate glass, on the light transmission of coated glass and the hardness of the coatings was studied. An increase in the concentration of hexadecyltrimethylammonium bromide in the sol from 1.37 × 10–2 to 5.20 × 10–2 M increases the maximum light transmission of glass with an antireflective coating from 94.7 to 99.0%, and minimum, from 84.7 to 93.6%, reduces the refractive index of the coating from 1.43 up to 1.27. The 3H–4H coating hardness acceptable for practice can be achieved provided that the maximum light transmission of glass with a single-layer double-sided coating is ≤96.0–97.0%, the refractive index of the antireflection coating is ≥1.35–1.36, and the maximum volume content of nanopores in the coating is not more than 20.0–23.0 vol % .
摘要：Calcium carbonate (CaCO3) nanoparticles have diverse applications in biomedicine, including ultrasound imaging, biosensing, drug delivery, and theranostics. One of its crystal polymorphs, vaterite, exhibits many unique features, such as its high solubility, porosity, and spherical shape, which make it suitable for drug delivery; however, the instability of this polymorph makes the large-scale fabrication of these particles challenging. In this work, we utilized a fast precipitation technique to fabricate CaCO3 hybrid particles, with the biocompatible polymeric additives bovine serum albumin (BSA) and polydopamine (PDA), a polymer with unique optical properties. The results showed that BSA and PDA can be used together to produce hybrid particles with variable sizes and polymorph compositions, depending on the reaction or mixing time applied. We also demonstrated that, by controlling other fabrication process parameters, including the PDA polymerization time, addition order of the salts, and the pairing of the salts with the polymer additives, we could tune the physicochemical properties of the resulting CaCO3 hybrid particles. These findings are important in designing hybrid particle systems with tailored properties for specific applications, including contrast-enhanced ultrasound and photoacoustic imaging, drug delivery, photothermal therapy, and cancer theranostics.
摘要：Using biomass materials as exfoliating agents to produce graphene is a promising strategy due to their biocompatibility, reproducibility and sustainability. However, it’s still a challenge to prepare high-concentration graphene dispersion using biomass exfoliating agents. Here, we present a green and facile method to prepare few layered graphene nanosheets in aqueous solution by one-pot ball milling in the presence of protein, casein (CN). The results show that CN protein could be acted as an efficient exfoliating and stabilizing agent, producing water-soluble graphene nanosheets with a concentration up to 2.14 mg ml−1. As CN protein contains both amino and carboxyl groups, thus the prepared graphene nanosheets decorated with CN protein (GN-CN) show zwitterionically charged character and thereby can be stably dispersed under both acidic and alkaline conditions. Moreover, the oven-dried GN-CN hybrid exhibits exceptional redispersibility in water with a concentration as high as 100 mg ml−1 and even more. Benefiting from the zwitterionic character, GN-CN shows the Pickering emulsion effect over a wide pH range. As a proof of concept, the application of the zwitterionic GN-CN as a Pickering emulsifier to prepare microcapsule phase change composite material has been successfully demonstrated.
摘要：Thrombin, a major protein involved in the clotting cascade by the conversion of inactive fibrinogen to fibrin, plays a crucial role in the development of thrombosis. Antithrombin nanoparticles enable site-specific anticoagulation without increasing bleeding risk. Here we outline the process of making and the characterization of bivalirudin and d-phenylalanyl-l-prolyl-l-arginyl-chloromethyl ketone (PPACK) nanoparticles. Additionally, the characterization of these nanoparticles, including particle size, zeta potential, and quantification of PPACK/bivalirudin loading, is also described.
摘要：Mussel-inspired dopamine (DA) self-polymerization over a variety of substrates has become a simple but versatile approach for synthesis of surface protein-imprinted materials. However, relatively high nonspecific binding to the imprinted polydopamine (PDA) coatings has long been an open problem because of their multifunctionalities. We herein propose a facile strategy for reduction of the nonspecific adsorption by covering the imprinted PDA coatings with slightly crosslinked nonlinear poly(ethylene glycol) (PEG) layers via aqueous precipitation polymerization before template removal. Vinyl groups are introduced onto the PDA coatings via Cu2+ mediated metal coordination for facilitating surface polymerization. The Cu2+ and embedded template are removed after polymerization. For proof of hypothesis, the protein imprinted PDA coatings were formed with SiO2 nanoparticles as representative nano-supports and lysozyme as a model protein template. Protein binding tests show that the grafted PEG layers with an optimized feed crosslinking degree can significantly enhance both recognition selectivity and specific binding capacity to the imprinted nanoparticles, typically with the imprinting factor increasing from 2.6 to 6.4. Also, the PEG layers can remarkably improve the stability of the PDA coatings in the acidic template removal solution. The presented strategy represents the first example for PEGylation of protein-imprinted PDA coatings, and may be extended for surface imprinting of other bio/organic molecules over other substrate materials.
摘要：The relationship between the short-term retrogradation dominated by amylose and the long-term retrogradation dominated by amylopectin still lacks specific experimental confirmation. In order to explore this relationship, four types of amylose crystal seeds (ACS) were prepared and added to native rice starch to intervene the long-term retrogradation. The average particle size of ACS was 200–450 nm. The maximum relative crystallinity of retrograded starch increased from 13.64% to 17.88% under the intervention of ACS. The ratio of absorbance at 1047 to 1022 cm−1 of retrograded starch increased from 0.670 to the maximum 0.887. The retrogradation rate constant increased significantly from 0.024 up to 0.051 d−1. The long-range order, short-range order, and retrogradation rate of retrograded starch all increased significantly, which indicated that the intervention of ACS promoted the long-term retrogradation of starch. These findings provided data support for the analysis of correlation between different stages of starch retrogradation.
摘要：A variety of three-dimensional DNA assemblies have been proposed as drug carriers owing to their good biocompatibility and easy fabrication. In this study, inspired by the structure of cockleburs, a novel aptamer-tethered DNA assembly was developed for effective targeted drug delivery. The Apt-nanocockleburs were fabricated via a facile process of DNA base pairing: four complementary DNA single strands, including one aptamer-ended strand and three sticky-end strands, were applied to pair with each other. The main body of the nanocockleburs can load doxorubicin (Dox) whilst the covered aptamer spines bind to the target MCF-7 cells.