Allredharmon4087
Herein we report the coating of visible light-driven polycaprolactone (PCL) based micromotors with an anti-biofouling poly lactic-co-glycolic acid (PLGA) layer for effective navigation and detoxification in blood samples. The micromotors encapsulate CdSe@ZnS quantum dots as photoresponsive materials and a Fe3O4 nanoparticle patch to promote electron transfer and reaction with glucose present in the media for diffusiophoretic propulsion in diluted blood. The coating of the micromotor with the PLGA layer prevents red blood cell adhesion and protein adsorption due to the creation of a highly efficient hydration layer. This results in an enhanced speed and efficient operation for enhanced toxin removal as compared with the bare PCL micromotors. Hemolysis and MTT assays along with no platelets aggregation revealed the high biocompatibility of the micromotors with living cells. Effective adsorptive removal of two relevant toxins, sepsis associated Escherichia coli O111B4 toxin and snake venom α-bungarotoxin from blood is achieved with the PLGA micromotors. The new developments illustrated here represent one step forward in the use of light-driven micromotors for biomedical applications.We investigate the interfacial compatibilization effect of reduced octadecylamine-functionalized graphene oxide (ODA-GO) on the morphological and rheological properties of immiscible homopolymer blends of polydimethylsiloxane (PDMS) and polyisoprene (PI). We prepared droplet-matrix blends with a PI PDMS ratio of 30 70 or 70 30 and interfacially localized ODA-GO stabilizer loadings from 0.1% to 1%. Blends were examined by optical microscopy and rheometry. Both blends show typical droplet-matrix morphology with stabilized round drops that do not stick together. With the addition of ODA-GO, smaller drops were observed in PI-continuous blends as compared to the PDMS-continuous blends suggesting that the effects of particles are not symmetric in the two cases. At sufficiently high ODA-GO loadings, flow-induced coalescence is suppressed almost completely. Dynamic oscillatory rheology broadly confirms the morphological observations. Specifically, all the blends show an interfacial relaxation process that is distinct from the bulk viscoelasticity, and the dependence of this process on GO content and flow conditions confirms the compatibilizing effect of the ODA-GO. This work provides a strategy for interfacially-compatibilizated polymer blends with specific properties for practical applications.Seeking all-nature derived antibacterial agents with effective disinfection function, high human safety as well as environment-friendly characteristics are highly required in the food industry. Herein, we report the lactoferrin-thymol (LF-Thy) complex as an effective killing agent against Gram-negative Escherichia coli (E. coli) and Gram-positive Staphylococcus aureus (S. aureus). The multi-spectroscopy results clearly demonstrate the combination of LF and Thy to form the LF-Thy complex, accompanied with LF conformation variations including the increase in the hydrophobicity of amino acid residues and changes in the types of secondary conformation distribution in LF. Molecular docking results show that LF exhibits three possible binding sites and five predicted stable binding modes for Thy with the help of hydrogen bonding and hydrophobic interactions. Moreover, LF-Thy demonstrated a significantly higher antibacterial ability compared to LF and displays effective disinfection function against E. coli and S. aureus. The minimum inhibitory concentration (MIC) of LF toward E. coli and S. aureus is >40 mg mL-1 and 40 mg mL-1, which decreases to 10 mg mL-1 and 5 mg mL-1 after combination with Thy, respectively. U0126 nmr This work demonstrates the promising antibacterial activities of the LF-Thy complex and provides an alternative agent for combating bacterial infection in the food industry, which holds great potential for promoting the development of the all-natural healthcare food complex.Transition metal sulfides (TMSs) are the most used electrode materials for supercapacitors (SCs). However, they still suffer from unsatisfactory electrochemical properties. Designing a hollow mixed TMS nanostructure with a well-defined chemical composition and shape is an effective strategy to tackle this issue, yet remains challenging. Herein, using a bimetallic zeolitic imidazolate framework (Zn-Co-ZIF) with various Zn/Co ratios as the template, a series of trimetallic sulfide (Ni-Zn-Co-S) hollow nanocages were successfully prepared by sequential nickel nitrate etching, co-precipitation and vulcanization. As an electrode material for a three-electrode SC in an aqueous alkaline electrolyte, the Ni-Zn-Co-S-0.25 electrode achieves an ultra-high specific capacitance of 1930.9 at 1 A g-1 with a good rate performance (64.5% at 10 A g-1). In order to further prove the advantage of the as-prepared Ni-Zn-Co-S-0.25 material, it was assembled into an asymmetric energy storage device using an activated carbon (AC) anode. The Ni-Zn-Co-S-0.25//AC cell exhibits an outstanding energy storage capability (32.8 W h kg-1 at 864.8 W kg-1) with a splendid cyclic life (retaining ∼92.2% of the initial capacitance after 10 000 cycles). The excellent electrochemical performance of Ni-Zn-Co-S-0.25 is ascribed to the merits of the trimetallic sulfide hollow nanocage i.e., good electronic conductivity, a large active surface area, fast charge transfer, rich redox reactions and the synergic effect of different metal ions.Aqueous suspensions of nanosheets are readily obtained by exfoliating low-dimensional mineral compounds like H3Sb3P2O14. The nanosheets self-organize, at low concentration, into a periodic stack of membranes, i.e. a lamellar liquid-crystalline phase. Due to the dilution, this stack has a large period of a few hundred nanometres, it behaves as a 1-dimensional photonic material and displays structural colours. We experimentally investigated the dependence of the period on the nanosheet concentration. We theoretically showed that it cannot be explained by the usual DLVO interaction between uniform lamellae but that the particulate nature of nanosheet-laden membranes must be considered. Moreover, we observed that adding small amounts of 100 kDa poly(ethylene oxide) (PEO) decreases the period and allows tuning the colour throughout the visible range. PEO adsorbs on the nanosheets, inducing a strong reduction of the nanosheet charge. This is probably due to the Lewis-base character of the EO units of PEO that become protonated at the low pH of the system, an interpretation supported by theoretical modeling. Oddly enough, adding small amounts of 1 MDa PEO has the opposite effect of increasing the period, suggesting the presence of an additional intermembrane repulsion not yet identified. From an applied perspective, our work shows how the colours of these 1-dimensional photonic materials can easily be tuned not only by varying the nanosheet concentration (which might entail a phase transition) but also by adding PEO. From a theoretical perspective, our approach represents a necessary step towards establishing the phase diagram of aqueous suspensions of charged nanosheets.A novel chromium(VI)-based compound, [(CH3CH2)3N(CH2Cl)][CrO3Cl] (1), undergoes a high-temperature phase transition at around 340.9 K, accompanied by an ultra-large entropy change of 63.49 J mol-1 K-1. Compound 1 exhibits a moderate ferroelectric polarization of 0.48 μC cm-2 and a remarkable CD signal. Strikingly, 1 occupies a narrow band gap of 2.22 eV, which is chiefly attributed to the inorganic [CrO3Cl]- tetrahedron. It is believed that these findings will contribute to an alternative pathway for the design of multifunctional ferroelectric materials, whose potential applications will be in semiconductors, energy storage, etc.The regiodivergent catalytic dehydrogenative cross-coupling reactions at both sp2 and sp3 hybridized carbons of aromatic compounds are particularly challenging. Herein, we report the finding of transient directing group controlled regiodivergent C(sp3)-C(sp2) and C(sp2)-C(sp2) cross-coupling in the o-methyl benzaldehyde frameworks. Catalyzed by palladium, using K2S2O8 or [F+] reagents as by-standing oxidants and unactivated arenes as substrates/solvents, various benzyl benzaldehydes or phenyl benzaldehydes were prepared. A mechanism study indicated that the regiospecificity is dominated by the [5,6]-fused palladacycle or [6,5]-fused palladacycle intermediates, which are generated from Pd-chelation with specified transient directing groups and further C-H activations.The magnetic tunneling junction (MTJ) controlled by electric field as an alternate approach for energy efficiency is the highlight for nonvolatile RAM, while there is still a lack of research on resistance manipulation with the electric field in nanoscale MTJs. In this study, we integrated nanoscale MTJs on the (011) orientated Pb(Mg1/3Nb2/3)0.7Ti0.3O3 (PMN-PT) ferroelectric substrates and systematically investigated the magnetoresistance as a function of the magnetic field and electric field. A single domain state of the nanoscale MTJ was demonstrated by the experimental result and theoretical simulation. Afterward, the obvious electric field control of R-H curves was obtained and explained by the competition between magnetoelastic energy and shape anisotropy. More importantly, simulation results also predicted that the switching pathway of magnetic moments under the magnetic field is strongly dependent on the applied electric field, displaying the electric field control of chiral switching in the nano-MTJ. Our work is a milestone in the realization of the emerging dubbed straintronics field.Tip-induced optical spectroscopy overcomes the inherent resolution limits of conventional optical techniques enabling studies of sub-nm sized objects due to the tip's near-field antenna action. This statement is true for individual molecules on surfaces or in the gas phase, but does not hold without restrictions for spatially extended samples. The reason is that the perturbations caused by the tip extend into the sample volume. The tip may induce strain, heating or hot-carrier injection locally in the material. These effects add additional degrees of complexity by changing near-field and far-field optical response. The far-field response varies because strain relaxation, heat and carrier diffusion possess areas of influence exceeding the sample area influenced by the short-range near-field effects. Tip-in spectra are not simply enhanced compared to tip-out spectra, they will also vary in spectral appearance, i.e., peak positions, relative peak intensities, and linewidths. Detailed studies of MoS2 samples ranging from a single layer to bulk-like multi-layer MoS2 also reveal that the spectra are sensitive to variations of phonon and band structure with increasing layer number. These variations have a direct impact on the signals detected, but also clearly modify the relative magnitudes of the contributions of the tip-induced effects to the tip-in spectra. In addition, the optical response is affected by the kind of tip and substrate used. Hence, the presented results provide further insight into the underlying microscopic mechanisms of tip-enhanced spectroscopy and demonstrate that 2D materials are an ideal playground for obtaining a fundamental understanding of these spectroscopic techniques.