In river water, milk, and bovine serum, molecularly imprinted polymer nanoparticles with hydrophilic polymer brushes showed excellent molecular recognition (see picture). Readily prepared by ...precipitation polymerization with a macromolecular chain‐transfer agent, such nanoparticles are promising alternatives to antibodies for many applications owing to their superior dispersion and binding properties in biological matrices.
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BFBNIB, FZAB, GIS, IJS, KILJ, NLZOH, NUK, OILJ, SAZU, SBCE, SBMB, UL, UM, UPUK
A facile, general, and highly efficient approach to obtain azobenzene (azo)-containing molecularly imprinted polymer (MIP) microspheres with both photo- and thermoresponsive template binding ...properties in pure aqueous media is described for the first time, which involves the first synthesis of “living” azo-containing MIP microspheres with surface-immobilized alkyl halide groups via atom transfer radical precipitation polymerization (ATRPP) and their subsequent modification via surface-initiated atom transfer radical polymerization (ATRP) of N-isopropylacrylamide (NIPAAm). The successful grafting of poly(NIPAAm) (PNIPAAm) brushes onto the obtained MIP microspheres was confirmed by FT-IR, SEM, water dispersion stability and static contact angle studies, and template binding experiments. The introduction of PNIPAAm brushes onto the azo-containing MIP microspheres significantly improved their surface hydrophilicity and imparted thermoresponsive properties to them, leading to their pure water-compatible and thermoresponsive template binding properties. In addition, the binding affinity of the imprinted sites in the grafted azo-containing MIP microspheres was found to be photoresponsive toward the template in pure water, and this photoregulation process proved to be highly repeatable under photoswitching conditions.
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IJS, KILJ, NUK, PNG, UL, UM
A new and efficient approach to obtaining molecularly imprinted polymers (MIPs) with both pure water-compatible (i.e., applicable in the pure aqueous environments) and stimuli-responsive binding ...properties is described, whose proof-of-principle is demonstrated by the facile modification of the preformed MIP microspheres via surface-initiated reversible addition–fragmentation chain transfer (RAFT) polymerization of
N-isopropylacrylamide (NIPAAm). The presence of poly(NIPAAm) (PNIPAAm) brushes on the obtained MIP microspheres was confirmed by FT-IR as well as the water dispersion and static contact angle experiments, and some quantitative information including the molecular weights and polydispersities of the grafted polymer brushes, the thickness of the polymer brush layers, and their grafting densities was provided. In addition, the binding properties of the ungrafted and grafted MIPs/NIPs in both methanol/water (4/1, v/v) and pure water solutions were also investigated. The introduction of PNIPAAm brushes onto the MIP microspheres has proven to significantly improve their surface hydrophilicity and impart stimuli-responsive properties to them, leading to their pure water-compatible and thermo-responsive binding properties. The application of the facile surface-grafting approach, together with the versatility of RAFT polymerization and the availability of many different functional monomers, makes the present methodology a general and promising way to prepare water-compatible and stimuli-responsive MIPs for a wide range of templates.
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GEOZS, IJS, IMTLJ, KILJ, KISLJ, NUK, OILJ, PNG, SAZU, SBCE, SBJE, UL, UM, UPCLJ, UPUK
Mucin 3A (MUC3A) is overexpressed in colorectal cancer (CRC) and associated with poor prognosis, but the related mechanism remains unclear. Our study found that MUC3A promotes the progression of CRC ...by activating the PI3K/Akt/mTOR signaling pathway. Knockout of MUC3A significantly inhibited the proliferation of CRC cells and induced G1 phase arrest by upregulating p21 protein, an important cell cycle regulator. Moreover, knockout of MUC3A significantly inhibited invasion ability and enhanced the sensitivity to the chemotherapeutic agent 5-FU. Furthermore, we found that knockout of MUC3A repressed the PI3K/Akt/mTOR pathway through RNA-seq. Treatment with the PI3K/Akt/mTOR pathway inhibitor rapamycin successfully eliminated the difference in proliferation, invasion and chemoresistance between MUC3A knockout cells and control cells. Our study suggests that MUC3A is a potential oncogene that promotes the proliferation, invasion, and chemotherapy resistance of CRC. Moreover, CRC patients with high expression of MUC3A may benefit from rapamycin treatment.
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DOBA, IZUM, KILJ, NUK, PILJ, PNG, SAZU, SIK, UILJ, UKNU, UL, UM, UPUK
A facile, general, and efficient one-pot approach to obtaining narrow or monodisperse, highly cross-linked, surface-functionalized, and “living” polymer microspheres with uniformly cross-linked ...structures by atom transfer radical precipitation polymerization (ATRPP) is described for the first time. The simple introduction of atom transfer radical polymerization (ATRP) mechanism into precipitation polymerization system allows the direct generation of uniformly cross-linked “living” polymer microspheres with their number-average diameters ranging from 0.73 to 3.25 μm and their polydispersity indices being typically lower than 1.01. The polymerization parameters (including stirring rate, monomer loading, initiator and catalyst concentrations, molar ratio of cross-linker to monovinyl functional comonomer, and polymerization scale and time) have proven to show significant influence on the morphologies of the resulting polymer microspheres, which makes it very convenient to control the particle sizes by easily tuning the reaction conditions. The general applicability of ATRPP was demonstrated by synthesizing a series of uniform functional copolymer microspheres with different incorporated functional comonomers (i.e, 4-vinylpyridine, acrylamide, and 2-hydroxyethyl methacrylate). Moreover, the “livingness” of the resulting polymer microspheres was confirmed by their direct grafting of hydrophilic polymer brushes via surface-initiated ATRP under mild reaction conditions. Furthermore, a “grafting from” particle growth mechanism is proposed for ATRPP, which is considerably different from the “grafting to” particle growth mechanism in the traditional precipitation polymerization.
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IJS, KILJ, NUK, PNG, UL, UM
In this contribution, a facile one-pot strategy is developed for the assembly of noble metal (Au and Pt) nanoparticles onto one-dimensional ZnO microrods using a green non-toxic reagent amino acid, ...lysine with two amino functional groups as the capping agent. Noble metal nanoparticles with a small size capped by lysine are formed and simultaneously anchored onto the surface of ZnO. No pre-functionalization of the ZnO support is needed, hence simplifying the synthesis and reducing the fabrication cost. Inspired by the catalytic properties of Au nanoparticles in both catalyst and sensor materials, we have examined the gas sensing performances towards ethanol detection. Obtained results demonstrate that after decoration by Au nanoparticles, the sensor shows significantly enhanced sensing performances in terms of high sensitivity, fast response and recovery, excellent reproducibility and good selectivity. The improved sensor properties are probably ascribed to the catalytic Au promoters and the Schottky barriers at the metal and semiconductor interface.
A one-pot strategy using lysine is developed to fabricate Au (Pt)/ZnO hybrid microrods, which can serve as advanced sensor materials.
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IJS, KILJ, NUK, UL, UM, UPUK
A novel, facile, and general one‐pot strategy is explored for the synthesis of diverse noble‐metal (Au, Pt, Ag, or Pt/Au)/Fe2O3 hybrid nanoparticles with the assistance of lysine (which is a ...nontoxic, user friendly amino acid that is compatible with organisms) and without using any other functionalization reagents. Control experiments show that lysine, which contains both amino and carboxylic groups, plays dual and crucial roles as both linker and capping agents in attaching noble metals with a small size and uniform distribution onto an Fe2O3 support. Considering the perfect compatibility of lysine with organism, this approach may find potentials in biochemistry and biological applications. Furthermore, this novel route is also an attractive alternative and supplement to the current methods using a silane coupling agent or polyelectrolyte for preparing hybrid nanomaterials. To demonstrate the usage of such hybrid nanomaterials, a chemical gas sensor has been fabricated from the as‐synthesized Au/Fe2O3 nanoparticles and investigated for ethanol detection. Results show that the hybrid sensor exhibits significantly improved sensor performances in terms of high sensitivity, low detection limit, better selectivity, and good reproducibility in comparison with pristine Fe2O3. Most importantly, this general approach can be further employed to fabricate other hybrid nanomaterials based on different support materials.
Dual control! A novel, facile, and general one‐pot strategy is explored for constructing diverse noble‐metal (Au, Pt, Ag or Pt/Au)/Fe2O3 hybrid nanoparticles by using lysine as a dual linker and capping reagent (see figure). The hybrid Au/Fe2O3 nanoparticles exhibit significantly improved sensor performance in terms of high sensitivity, low detection limit, good selectivity, and reproducibility in comparison to pristine Fe2O3.
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BFBNIB, FZAB, GIS, IJS, KILJ, NLZOH, NUK, OILJ, SAZU, SBCE, SBMB, UL, UM, UPUK
Polypyrrole-coated SnO2 hollow spheres hybrid materials have been synthesized through an in situ polymerization of pyrrole monomers in the presence of preprepared SnO2 hollow spheres. The hybrids ...were characterized by transmission electron microscopy (TEM), scanning electron microscopy (SEM), X-ray diffraction (XRD), Fourier transform infrared spectrometer (FTIR), and thermogravimetric analysis (TG). Experimental data showed certain synergetic interaction existed in the hybrids, probably resulting in the enhanced thermal stability of polypyrrole coatings. Gas sensing tests showed that the hybrids possessed very fast response and high sensitivity to ammonia gas at room temperature, implying its potential application for gas sensors.
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IJS, KILJ, NUK, PNG, UL, UM
ZnO hollow spheres were successfully prepared by using carbon microspheres as templates and characterized by X-ray diffraction (XRD) analysis, scanning electron microscope (SEM), transmission ...electron microscope (TEM) and selected area electron diffraction (SAED). A gas sensor was fabricated from the as-prepared ZnO hollow spheres and tested to different concentrations of NH
3 and NO
2 at different operating temperatures. The results showed that the ZnO hollow-sphere sensor exhibited extremely different sensing behaviors to NH
3 and NO
2. The optimum operating temperature of the sensor was 220
°C for NH
3 and 240
°C for NO
2, respectively. At 220
°C, the responses to 25, 50 and 75
ppm NH
3 were 7.9, 11.1 and 20.4 and the response times were as long as several minutes. At 240
°C, the responses to 10, 50 and 100
ppm NO
2 were 140.6, 172.8 and 286.8 and the corresponding response times were 31, 19 and 9
s. In addition, it is also shown that the gas sensor exhibited much higher response to NO
2 than to other gases at 240
°C, implying the good selectivity and potential application of the sensor for detecting NO
2.
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GEOZS, IJS, IMTLJ, KILJ, KISLJ, NUK, OILJ, PNG, SAZU, SBCE, SBJE, UL, UM, UPCLJ, UPUK, ZRSKP
Astrocyte elevated gene-1 (AEG-1), upregulated in various types of human cancers, has been reported to be associated with the carcinogenesis of human cancer. However, the functional significance of ...AEG-1 in human esophageal squamous cell carcinoma (ESCC) remains unknown. In the present study, we showed the expression of AEG-1 was markedly upregulated in esophageal cancer cell lines and surgical ESCC specimens at both transcriptional and translational levels. Immunohistochemical analysis revealed that 80 of 168 (47.6%) paraffin-embedded archival ESCC specimens exhibited high levels of AEG-1 expression. Statistical analysis suggested the upregulation of AEG-1 was significantly correlated with the clinical staging of the ESCC patients (P = 0.001), T classification (P = 0.002), N classification (P = 0.034), M classification (P = 0.021) and histological differentiation (P = 0.035) and those patients with high AEG-1 levels exhibited shorter survival time (P < 0.001). Multivariate analysis indicated that AEG-1 expression might be an independent prognostic indicator of the survival of patients with ESCC. Furthermore, we found that ectopic expression of AEG-1 in ESCC cells could significantly enhance cell proliferation and anchorage-independent growth ability. Conversely, silencing AEG-1 by short hairpin RNAi caused an inhibition of cell growth and anchorage-independent growth ability on soft agar. Moreover, we demonstrated that the upregulation of AEG-1 could reduce the expression of p27Kip1 and induce the expression of cyclin D1 through the AKT/FOXO3a pathway. Our findings suggest that the AEG-1 protein is a valuable marker of ESCC progression and that the upregulation of AEG-1 plays an important role in the development and pathogenesis of human ESCC.
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