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Reversible Pickering emulsions, achieved by switchable, interfacially active colloidal particles, that enable on-demand emulsification/demulsification or phase inversion, hold substantial promise for biphasic catalysis, emulsion polymerization, cutting fluids, and crude oil pipeline transportation. However, particles with such a responsive behavior usually require complex chemical syntheses and surface modifications, limiting their extensive use. Herein, we report a simple route to generate emulsions that can be controlled and reversibly undergo phase inversion. The emulsions are prepared and stabilized by the interfacial assembly of polyoxometalate (POM)-polymer, where their electrostatic interaction at the interface is dynamic. The wettability of the POMs that dictates the emulsion type can be readily regulated by tuning the number of polymer chains bound to POMs, which, in turn, can be controlled by varying the concentrations of both components and the water/oil ratio. In addition, the number of polymer chains anchored to the POMs can be varied by controlling the number of negative charges on the POMs through an in situ redox reaction. As such, a reversible inversion of the emulsions can be triggered by switching between exposure to ultraviolet light and the introduction of oxygen. Combining the functions of POM itself, a cyclic interfacial catalysis system was realized. Inversion of the emulsion also affords a pathway to high-internal-phase emulsions. The diversity of the POMs, the polymers, and the responsive switching groups open numerous new, simple strategies for designing a wide range of responsive soft matter for cargo loading, controlled release, and delivery in biomedical and engineering applications without time-consuming particle syntheses.
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Emulsion gels, also known as gelled emulsions or emulgels, have garnered great attention both in fundamental research and practical applications due to their superior stability, tunable morphology and microstructure, and promising mechanical and functional properties. From an application perspective, attention in this area has been, historically, mainly focused on food industries, e.g., engineering emulsion gels as fat substitutes or delivery systems for bioactive food ingredients. However, a growing body of studies has, in recent years, begun to demonstrate the full potential of emulsion gels as soft templates for designing advanced functional materials widely applied in a variety of fields, spanning chemical engineering, pharmaceutics, and materials science. Herein, a concise and comprehensive overview of emulsion gels is presented, from fundamentals to applications, highlighting significant recent progress and open questions, to scout for and deepen their potential applications in more fields.
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Emulsion as a fine dispersion of immiscible liquids has involved widespread applications in industry, pharmaceuticals, agriculture, and personal care. Stimuli-responsive emulsions capable of on-demand demulsification or changing their properties are required in many cases such as controllable release cargo, oil recovery, emulsifier recycling, and product separation, great progress is achieved in these areas. Among these various triggers, much effort is made to develop physical stimuli, due to the noninvasive and environmentally friendly characteristics. Physical stimuli-responsive emulsions provide plenty of valuable practical applications in the fields of sustainable industry, biomedical reaction, drug delivery. Here, the recent development in the field of emulsions in response to physical stimuli consisting of temperature, light, magnetic fields, electrical fields, etc., is summarized. The preparation methods and mechanisms of physical stimuli-responsive emulsions and their applications of catalysis reaction, drug delivery, and oil recovery are highlighted in this review. The future directions and outstanding problems of the physical stimuli-responsive emulsions are also discussed.
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Sistemas de Liberación de Medicamentos , Emulsiones , TemperaturaRESUMEN
Structural colors particularly of the angle-independent category stemming from wavelength-dependent light scattering have aroused increasing interest due to their considerable applications spanning displays and sensors to detection. Nevertheless, these colors would be heavily altered and even disappear during practical applications, which is related with the variation of refractive index mismatch by liquid wetting/infiltrating. Inspired by bird feathers, we propose a simple deposition toward the coating with angle-independent structural color and superamphiphobicity. The coating is composed of â¼200 nm-sized channel-type structures between hollow silica and air nanostructures, exhibiting a robust sapphire blue color independent of intense liquid intrusion, which duplicates the characteristics of the back feather of Eastern Bluebird. A high color saturation and superamphiphobicity of the biomimetic coating are optimized by manipulating the coating parameters or adding black substances. Excellent durability under harsh conditions endows the coating with long-term service life in various extreme environments.
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Responsive nanoparticle surfactants (NPSs) can dynamically and reversibly modulate the interfacial interactions between incompatible components, which are essential in the interfacial catalysis, corrosion, and self-assembly of block copolymers (BCPs). However, NPSs with stimuli-responsive behavior often involve tedious chemical synthesis and surface modifications. Herein, we propose a strategy to in situ construct a kind of dynamic and reversible NPSs by the interfacial electrostatic interaction between the negatively charged nanoparticles (NPs) and the positively charged homopolymers. The NPSs assembled at the oil/water interface reduce the interfacial tension and direct the confined assembly of BCP. Meanwhile, the dynamic NPSs can be disassembled by increasing the pH value or introducing competitive electrostatic attractions, which can dynamically and reversibly change the interfacial properties as well as the alignment of polymer chains, enabling BCP microparticles with reversibly switchable lamellar and cylindrical structures. Furthermore, by the introduction of aggregation-induced emission luminogens as tails to the NPSs, the reversible transformation of BCP microparticles can be visualized by fluorescence emission, which is dependent on the nanostructures of microparticles. This work establishes a concept for dynamically manipulating interfacial interactions and reversibly switching BCP microparticles without time-consuming NPS synthesis, showing promising applications in the fabrication of smart materials with switchable structures and properties.
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Janus particles, having the property integration of each component, have attracted increasing attention due to their considerable potential in the field of material engineering applications. However, organic solvents or sophisticated equipment during the fabrication processes is generally inevitable. Here, we report a facile route to prepare Janus droplets and hydrogels via aqueous two-phase systems (ATPS). Simply merging two polymers, i.e., polyethylene glycol (PEG) and dextran (DEX), as aqueous droplets on a superamphiphobic surface leads to phase separation, provided that their concentrations exceed the threshold in the mixed aqueous droplets, thus generating a Janus structure. Various morphologies of such Janus droplets can be well controlled by manipulating the locations of these two polymers' concentration on the phase diagram, and the evolution of the mixed droplets are deterministic on the basis of the kinetics of their phase separation and the degree of hydrophobicity of the substrate. Introducing monomers and/or nanoparticles, further, into a certain phase of the ATPS droplet followed by photopolymerizing enables Janus hydrogel particles with diverse functionalities to be obtained. The ease and green techniques with which the Janus balance and curvature between two phases of the Janus droplet can be finely tuned point to new directions in designing Janus particles and hold great promises in biological engineering.
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BACKGROUND: With the feature of destructive and biliary malignancy, intrahepatic cholangiocarcinoma (ICC), presents unclear molecular mechanisms which contributes to typically poor prognosis for patients. Seizure-related 6 homolog-like 2 (SEZ6L2) is a gene that encodes for a seizure-associated protein localized on the cell surface. Thus far, the function of SEZ6L2 in ICC has not been reported. METHODS: We used data from The Cancer Genome Atlas and the Gene Expression Omnibus to analyze dynamics behind and levels of expression of SEZ6L2 in ICC. Then we used qRT-PCR and Immunohistochemical staining to detect levels of expression of SEZ6L2 and thereby determined the potential clinical significance of this protein in ICC. RESULTS: According to qRT-PCR and immunohistochemical analysis results, SEZ6L2 was overexpressed in ICC. Kaplan-Meier and Cox proportional hazard analyses indicated that patients afflicted by ICC with high levels of relative expression of SEZ6L2 have a poorer prognosis and that SEZ6L2 may be an independent prognostic factor which enables to the accurate prediction of overall survival (OS) and disease-free survivals' (DFS) expected rates. Subcutaneous xenograft models used to explore the role of SEZ6L2 in tumor formation in vivo. The dynamics of the SEZ6L2 gene being promote angiogenesis in cholangiocarcinoma are related to increasing expressive growth factors which include EGF, VEGF, PDGF and the activation of the P38-MAPK pathway. CONCLUSIONS: Our findings suggest that SEZ6L2 can serve as an advanced biomarker that can be used to accurately predict a patient prognosis and be used as a target for ICC treatment.
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PURPOSE: Renal cell cancer (RCC) is one of the primary causes of malignancy deaths all over the world. The most important cause of RCC-related mortality is metastasis. Epithelial-mesenchymal transition (EMT) plays an important role in metastasis of malignant tumors including RCC. miR-1-3p is confirmed to be decreased in many types of cancer. Nevertheless, the function of miR-1-3p in RCC metastasis and EMT process was still unclear. MATERIALS AND METHODS: In this study, information from clinical investigation, in vitro study, and in vivo study discovered miR-1-3p expression character and its status in RCC. The character of miR-1-3p in invasive and metastatic properties in vitro and in vivo was also inspected in RCC cells and xenograft tumor model, and expression levels of EMT markers were evaluated in RCC cells and tissues. RESULTS: miR-1-3p was proved to be decreased in RCC cell lines and tissues compared with normal renal cells and tissues. miR-1-3p expression level in RCC tissues was closely related with capsulation, lymph node metastasis, and vascular invasion. miR-1-3p was found to be able to block the EMT process in A498 and CAKI-1 RCC cells and tumors. Luciferase reporter assay and expression level rescue assays were employed to reveal that miR-1-3p inhibited the invasion and migration property of RCC cells by directly targeting Fibronectin 1. Upregulation of Fibronectin 1 partially reversed the suppressive effect of miR-1-3p on EMT process. CONCLUSION: In brief, this study has verified that miR-1-3p blocked the EMT process of RCC cells by reducing Fibronectin 1 expression. miR-1-3p/Fibronectin 1 axis may be considered as a new target for drug development of RCC.
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Traditional superhydrophobic cotton fabrics (SCFs) for oil/water separation were usually fabricated by surface coating with inorganic nanoparticles combined with nonrenewable and nonbiodegradable or even toxic fossil-based chemicals, which would lead to secondary environmental pollution after their lifetime. In this study, we report robust, nanoparticle-free, fluorine-free SFC, which was prepared by acid etching followed by surface coating with epoxidized soybean oil resin (CESO) and subsequent modification with stearic acid (STA). No toxic compound and no nanoparticle were included within the SCF and all the raw materials including cotton fabric, CESO and STA are biodegradable and derived from biological resources. The SCF showed excellent mechanical stability and chemical/environmental resistances. The superhydrophobicity of the SFC survived from mechanical abrasion, tape peeling, ultrasonication, solvent erosion and low/high temperature exposure. The SCF also exhibited good acid/alkali resistance with contact angle over 150° toward different pH water droplets. Moreover, the SCF could efficiently separate oil/water mixtures with efficiency above 97.9% and the superhydrophobicity remained after reusing for at least 10 times. The fully biological-derived SCF with excellent mechanical and chemical resistances exhibit great potential for separation of oil/water mixtures.
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Fibra de Algodón , Interacciones Hidrofóbicas e Hidrofílicas , Nanopartículas/química , Aceite de Soja/química , Agua/química , Ácidos Decanoicos/química , Ácidos Dicarboxílicos/química , Temperatura , HumectabilidadRESUMEN
Cellulose nanocrystal (CNC) with renewability, biodegradability, and nanoscale size was used as the rough structure component instead of inorganic nanoparticles to fabricate renewable and degradable superhydrophobic cotton fabric via a dip-coating method with cured epoxidized oil resin (CESO) as the binder. The superhydrophobic cotton fabric could selectively absorb oil from oily water and could separate various oil/water mixture very efficiently with separation efficiency higher than 98%. The superhydrophobic cotton fabric showed excellent stability, making it reusable for several times without lowering separation efficiency. Moreover, the superhydrophobic cotton fabric exhibited excellent solvent and chemical resistances. Furthermore, the superhydrophobic cellulosic fabric was degradable with weight loss of 14.4 wt% after hydrolytic degradation in phosphate buffer solution (pH 7.4) at 37 °C for 10 weeks. The superhydrophobic cotton fabric may exhibit great viability as sustainable and degradable alternative to traditional nonrenewable and non-degradable superhydrophobic materials in oil/water separation.
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Protein tyrosine phosphatase 4A2 (PTP4A2) has been implicated as an oncogenic protein in several human cancers. However, the level of PTP4A2 expression and its prognostic significance in nasopharyngeal carcinoma (NPC) remains unknown. In this study, Western blotting (WB), quantitative real-time PCR (qT-PCR) and immunohischemistry (IHC) was applied to evaluated the expression levels of PTP4A2 in NPC cell lines and tumor tissues combining two independent cohorts. Receiver-operator curve (ROC) analysis was used to assessed the optimal cut-off score in training cohort (266 cases). This cut-off score was subjected to determine the association of PTP4A2 expression with patients' clinical characteristics and survival outcome in the validation cohort (201 cases) and the overall population (467 cases). We found that PTP4A2 were significantly overexpressed in NPC cell lines compared with normal nasopharyngeal epithelial cell. Moreover, overexpression of PTP4A2 was positively correlated with advanced T classification (P<0.001) and TNM stages (P<0.001). And higher PTP4A2 expression was an independent prognostic factor for adverse overall survival (P<0.05) and poor disease-free survival (P<0.05). Our results demonstrated that the overexpression of PTP4A2 was closely associated with poor survival outcome in patients with NPC and may represent a novel prognostic biomarker and therapeutic target for this disease.
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BACKGROUND AND AIMS: Hepatocellular carcinoma (HCC) is one of the most common malignancies worldwide. Aberrant activation of sonic hedgehog (Shh) signaling pathway plays important roles in tumorigenesis and progression of several tumors. Cyclopamine, an important inhibitor of Shh signaling pathway, can induce cell apoptosis. However, the mechanisms underlying cyclopamine-induced apoptosis are not well understood. The aim of this study is to determine the expression of the Shh signaling pathway components in HCC and to investigate the mechanisms underlying cyclopamine-induced apoptosis in HCC cells. METHODS: Shh signaling components (Shh, Ptch, Smo and Gli-1) expression levels were evaluated by immunohistochemistry on tissue microarrays containing 98 HCCs with paired adjacent noncancerous liver tissues. The relationships between sonic hedgehog signal pathway and clinicopathological factors were analyzed in HCC. Cell viability was analyzed by 3-(4,5-dimethylthiazol-2-yl)-2,5-diphenyl tetrazolium bromide (MTT) assay. Apoptosis was detected by flow cytometry. mRNA and protein levels were analyzed by RT-PCR and Western blot, respectively. RESULTS: Shh, Ptch, Smo and Gli-1 were overexpressed in HCC tissues compared with paired adjacent noncancerous liver tissue. Activated Shh signaling pathway was associated with tumor size, capsular invasion and vascular invasion in HCC. Cyclopamine remarkably decreased cell viability, induced apoptosis and downregulated Bcl-2 expression in HCC cells. CONCLUSIONS: Shh signaling pathway plays an important role in HCC tumorigenesis and progression, indicating that Shh signaling pathway is a potential therapeutic target for HCC. Cyclopamine induces apoptosis through downregulating Bcl-2 in HCC.