Enhancement of the Piezocatalytic Response of La-Doped BiFeO Nanoparticles by Defects Synergy.

Because of their intrinsic polarization and related properties, ferroelectrics attract significant attention to address energy transformation and environmental protection. Here, by using trivalent-ion-lanthanum doping of BiFeO nanoparticles (NPs), it is shown that defects and piezoelectric potential are synergized to achieve a high piezocatalytic effect for decomposing the model Rhodamine B (RhB) pollutant, reaching a record-high piezocatalytic rate of 21 360 L mol min (i.e.

Nano-size cobalt-doped cerium oxide particles embedded into graphitic carbon nitride for enhanced electrochemical sensing of insecticide fenitrothion in environmental samples: An experimental study with the theoretical elucidation of redox events.

In the present work, a nanocomposite, based on embedding Co-doped CeO nanoparticles into graphitic carbon nitride (g-CN), was applied to functionalize commercial glassy carbon paste. This is the first application of the electrochemical sensor, developed through the proposed procedure, in electrochemical sensing. The sensor was utilized for the electrochemical determination of organophosphate pesticide fenitrothion (FNT).

Epoxide Hydrolases: Multipotential Biocatalysts.

Epoxide hydrolases are attractive and industrially important biocatalysts. They can catalyze the enantioselective hydrolysis of epoxides to the corresponding diols as chiral building blocks for bioactive compounds and drugs. In this review article, we discuss the state of the art and development potential of epoxide hydrolases as biocatalysts based on the most recent approaches and techniques.

A General Synthetic Route to High-Quality Perovskite Oxide Nanoparticles and Their Enhanced Solar Photocatalytic Activity.

The main limitations of current methods for synthesizing perovskite oxide (ABO ) nanoparticles (NPs), e.g., the high reagent costs and sophisticated equipment, the long time and high-temperature processing, or multiple post-processing and thermal treatment steps, hamper their full study and potential application.

Nanocrystalline TiO/TiCT MXene composites with a tunable work function prepared using atmospheric pressure oxygen plasma.

Composites of TiO and TiCT MXene are of great interest because they combine superior TiO photocatalytic activity with excellent MXene conductivity. As these composites have conventionally been prepared using methods requiring high temperatures, a process for producing similar materials at reduced temperature could be beneficial for applications in flexible and printed electronics. Therefore, we used low-temperature dielectric barrier discharge to develop a method for forming crystalline TiO by treating TiCT MXene surfaces with high-power-density oxygen plasma comprising various energetic and reactive oxygen species, which oxidize MXene surfaces and form TiO nanoparticles on disordered graphitic carbon sheets within a few seconds.

Facile fabrication of screen-printed MoS electrodes for electrochemical sensing of dopamine.

Molybdenum disulfide (MoS) screen-printed working electrodes were developed for dopamine (DA) electrochemical sensing. MoS working electrodes were prepared from high viscosity screen-printable inks containing various concentrations and sizes of MoS particles and ethylcellulose binder. Rheological properties of MoS inks and their suitability for screen-printing were analyzed by viscosity curve, screen-printing simulation and oscillatory modulus.

Gallic acid-coated silver nanoparticles as perspective drug nanocarriers: bioanalytical study.

The ability of silver nanoparticles (AgNPs) to be used as drug nanocarriers has helped rapidly to invent novel strategies to treat diseases, such as cancer. The nanoparticles may offer a valuable tool to novel pH-sensitive drug delivery systems in the present scenario because of their undergoing mechanisms associated with the regulated dissolution, aggregation, and generation of oxygen radicals as well. These processes could be monitored by electrochemical (bio)sensors that are less money and time-consuming compared to other analytical approaches, however, with comparable analytical performance.

Lectin-Based Protein Microarray for the Glycan Analysis of Colorectal Cancer Biomarkers: The Insulin-Like Growth Factor System.

Lectin-based protein microarrays are used for glycoprofiling of various kinds of biological samples. Here we describe lectin-based microarray assay in the reverse-phase format where glycoprotein samples are spotted onto microarray slide and then are incubated with set of lectins. This configuration allows high-throughput screening of a large cohort of samples by a set of lectins without need of separation of glycans from glycoproteins.

Simulation-based optimisation of thermodynamic conditions in the ESEM for dynamical in-situ study of spherical polyelectrolyte complex particles in their native state.

We present a complex analysis and optimisation of dynamic conditions in the environmental scanning electron microscope (ESEM) to allow in-situ observation of extremely delicate wet bio-polymeric spherical particles in their native state. According to the results of gas flow and heat transfer simulations, we were able to develop an improved procedure leading to thermodynamic equilibrium between the sample and chamber environment. To quantify and hence minimise the extent of any sample deformation during specimen chamber pumping, a strength-stress analysis is used.

Crystal Growth Mechanisms of BiFeO Nanoparticles.

A wet-chemical synthesis process was designed to obtain reproducible single-phase multiferroic BiFeO nanoparticles. The phase purity, single crystallinity, and size of the nanoparticles are confirmed through the analysis of X-ray diffraction patterns, Raman spectroscopy, and high resolution transmission electron microscopy experiments. Crystal nucleation happens within the amorphous-rich area in multiple seeds, leading to the formation of single crystalline nanoparticles with no preferential faceting.

Surface Proximity Effect, Imprint Memory of Ferroelectric Twins, and Tweed in the Paraelectric Phase of BaTiO.

We have used energy-filtered photoemission electron microscopy (PEEM) at the photoemission threshold to carry out a microscopic scale characterization of the surface charge and domain structure of the (001) surface in BaTiO. Signatures of ferroelectric and ferroelastic domains, and tweed, dominate the surface structure of BaTiO at room temperature. The surface ferroic signatures are maintained on heating to temperature (~550 K), well above the transition temperature (393 K).

Baeyer-Villiger oxidations: biotechnological approach.

Baeyer-Villiger monooxygenases (BVMOs) are a very well-known and intensively studied class of flavin-dependent enzymes. Their substrate promiscuity, high chemo-, regio-, and enantioselectivity are prerequisites for the use in synthetic chemistry and should pave the way for successful industrial processes. Nonetheless, only a very limited number of industrial relevant transformations are known, mainly due to the lack of BVMOs stability and cofactor dependency.

A lectin-based cell microarray approach to analyze the mammalian granulosa cell surface glycosylation profile.

The high complexity of glycome, the repertoire of glycans expressed in a cell or in an organism, is difficult to analyze and the use of new technologies has accelerated the progress of glycomics analysis. In the last decade, the microarray approaches, and in particular glycan and lectin microarrays, have provided new insights into evaluation of cell glycosylation status. Here we present a cell microarray method based on cell printing on microarray slides for the analysis of the glycosylation pattern of the cell glycocalyx.

Principal component analysis for the forensic discrimination of black inkjet inks based on the Vis-NIR fibre optics reflection spectra.

Nineteen black inkjet inks of six different brands were examined by fibre optics reflection spectroscopy in Visible and Near Infrared Region (Vis-NIR FORS) directly on paper with a view to achieving good resolution between them. These different inks were tested on nineteen different inkjet printers from three brands. Samples were obtained from prints by reflection probe.

Negative-pressure-induced enhancement in a freestanding ferroelectric.

Ferroelectrics are widespread in technology, being used in electronics and communications, medical diagnostics and industrial automation. However, extension of their operational temperature range and useful properties is desired. Recent developments have exploited ultrathin epitaxial films on lattice-mismatched substrates, imposing tensile or compressive biaxial strain, to enhance ferroelectric properties.

Lectin-based protein microarray analysis of differences in serum alpha-2-macroglobulin glycosylation between patients with colorectal cancer and persons without cancer.

Glycosylation is co- and posttranslational modifications affecting proteins. The glycopattern changes are associated with changes in biological function and are involved in many diseases including cancer. We present the lectin-based protein microarray method enabling determination of differences in protein glycosylation.

Whole-cell Gluconobacter oxydans biosensor for 2-phenylethanol biooxidation monitoring.

A microbial biosensor for 2-phenylethanol (2-PE) based on the bacteria Gluconobacter oxydans was developed and applied in monitoring of a biotechnological process. The cells of G. oxydans were immobilized within a disposable polyelectrolyte complex gel membrane consisting of sodium alginate, cellulose sulphate and poly(methylene-co-guanidine) attached onto a miniaturized Clark oxygen electrode, forming whole cell amperometric biosensor.

Physical and bioengineering properties of polyvinyl alcohol lens-shaped particles versus spherical polyelectrolyte complex microcapsules as immobilisation matrices for a whole-cell Baeyer-Villiger monooxygenase.

Direct comparison of key physical and chemical-engineering properties of two representative matrices for multipurpose immobilisations was performed for the first time. Polyvinyl alcohol lens-shaped particles LentiKats® and polyelectrolyte complex microcapsules were characterised by advanced techniques with respect to the size distribution of the particles, their inner morphology as revealed by fluorescent probe staining, mechanical resistance, size-exclusion properties, determination of effective diffusion coefficient and environmental scanning electron microscope imaging. While spherical polyelectrolyte complex microcapsules composed of a rigid semipermeable membrane and a liquid core are almost uniform in shape and size (diameter of 0.

Perspectives in glycomics and lectin engineering.

This chapter would like to provide a short survey of the most promising concepts applied recently in analysis of glycoproteins based on lectins. The first part describes the most exciting analytical approaches used in the field of glycoprofiling based on integration of nanoparticles, nanowires, nanotubes, or nanochannels or using novel transducing platforms allowing to detect very low levels of glycoproteins in a label-free mode of operation. The second part describes application of recombinant lectins containing several tags applied for oriented and ordered immobilization of lectins.

Giant ultrafast photo-induced shear strain in ferroelectric BiFeO3.

Generation of strain using light is a key issue for future development of ultrasonic devices. Up to now, photo-induced GHz-THz acoustic phonons have been mainly explored in metals and semiconductors, and in artificial nanostructures to enhance their phononic emission. However, despite their inherent strong polarization (providing natural asymmetry) and superior piezoelectric properties, ferroelectric oxides have been only poorly regarded.

Biocatalysis with Escherichia coli-overexpressing cyclopentanone monooxygenase immobilized in polyvinyl alcohol gel.

Unlabelled: This is the first reported study on the immobilization of living recombinant Escherichia coli cells that overexpress cyclopentanone monooxygenase in polyvinyl alcohol gel particles LentiKats®. Immobilized cells overexpressing cyclopentanone monooxygenase have been used as a model of biocatalyst for enantioselective Baeyer-Villiger biooxidation of rac-bicyclo[3.2.

The direct magnetoelectric effect in ferroelectric-ferromagnetic epitaxial heterostructures.

Ferroelectric (FE) and ferromagnetic (FM) materials engineered in horizontal heterostructures allow interface-mediated magnetoelectric coupling. The so-called converse magnetoelectric effect (CME) has been already demonstrated by electric-field poling of the ferroelectric layers and subsequent modification of the magnetic state of adjacent ferromagnetic layers by strain effects and/or free-carrier density tuning. Here we focus on the direct magnetoelectric effect (DME) where the dielectric state of a ferroelectric thin film is modified by a magnetic field.

Microbial monooxygenase amperometric biosensor for monitoring of Baeyer-Villiger biotransformation.

A whole-cell amperometric biosensor consisting of genetically engineered Escherichia coli immobilised in polyelectrolyte membrane onto a miniaturised oxygen electrode was developed and used for monitoring of biotransformation based on Baeyer-Villiger oxidation. Baeyer-Villiger oxidation is commonly performed using microorganisms overexpressing Baeyer-Villiger monooxygenase enabling the production of enantiopure lactones or esters used in pharmaceutical industry. The biorecognition element, genetically modified E.

Label-free detection of glycoproteins by the lectin biosensor down to attomolar level using gold nanoparticles.

We present here an ultrasensitive electrochemical biosensor based on a lectin biorecognition capable to detect concentrations of glycoproteins down to attomolar (aM) level by investigation of changes in the charge transfer resistance (Rct) using electrochemical impedance spectroscopy (EIS). On polycrystalline gold modified by an aminoalkanethiol linker layer, gold nanoparticles were attached. A Sambucus nigra agglutinin was covalently immobilised on a mixed self-assembled monolayer formed on gold nanoparticles and finally, the biosensor surface was blocked by poly(vinyl alcohol).