Shielding of the specific body organ using the biocompatible material helps preventing direct exposure of that part to the foreign entities responsible for infections. Here we show the potential of ...the A2 milk protein recovered from the milk of cow from Indian origin for possible prevention of the direct exposure to other foreign molecules. We measured the surface pressure of the monolayers of different types of protein samples using Langmuir isotherm experiments. The surface pressure measurements for the monolayer of four types of protein macromolecules have been carried out using the Wilhelmy plate micro pressure sensor. We studied the self-organization of different protein macromolecules and their monolayer compression characteristics. The electrochemical behaviour is studied using electrochemical impedance spectroscopy. We found the highest surface pressure for the monolayer of A2 protein. Further, it is also found that A2 protein exhibited the highest surface activity amongst the other proteins. This property can be effectively used for making the envelope of the A2 protein surrounding the targeted entity.
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We study the dynamics of vortices in a two-dimensional, nonequilibrium system, described by the compact Kardar-Parisi-Zhang equation, after a sudden quench across the critical region. Our exact ...numerical solution of the phase-ordering kinetics shows that the unique interplay between nonequilibrium and the variable degree of spatial anisotropy leads to different critical regimes. We provide an analytical expression for the vortex evolution, based on scaling arguments, which is in agreement with the numerical results, and confirms the form of the interaction potential between vortices in this system.
DNA based nanostructures provide a versatile foundation because they exhibit fascinating luminescent and detection properties. Among such DNA nanostructures, DNA assembled fluorescent metal ...nanoclusters (NCs), such as silver (Ag), gold (Au) and copper (Cu) nanoclusters, as a new class of fluorophore have attracted progressively more attention owing to their unique electronic structures and the subsequent unusual physical and chemical properties. These excellent properties make them ideal luminescent probes for bio-chemical applications. Blending of metal with DNA sequences as a stabilizing agent has generated a large number of biosensors, as well as imaging and catalytic properties. To date, significant efforts have been devoted to the synthesis, properties and application studies of DNA hosted Au, Ag and Cu NCs. In this review article, we focus on summarizing recent advances in controllable synthesis of DNA, nucleotide-templated NCs strategies and emerging applications of metal NCs, including Au, Ag and Cu. Finally, we conclude with the enduring goal of this area of research, which could explore as novel promisingly environmental-benign approaches to construct nano clusters through DNA-based conjugation and modulation.
In this review, we have discussed the emergence of promising environmental-benign DNA assembled fluorescent metal nanoclusters and their unique electronic structures, unusual physical and chemical properties.
The local structure and atomic packing in CuxZr100−x (46≤x≤70) alloys have been investigated using classical molecular dynamics. We convincingly demonstrate that the atomic packing efficiency of the ...polytetrahedral clusters strongly correlates with the glass-forming ability. It is found that the full-icosahedra (<0,0,12,0>), which is considered to be a key local structural feature associated with the glass formation in metallic alloys, alone cannot explain the compositional dependence of glass-forming ability. We suggest that the population of the so-called defected icosahedra (<0,2,8,2>), apart from the full-icosahedra, could be crucial to account for the observed high atomic packing efficiency in the best glass-forming compositions.
•Local structure and atomic packing in CuxZr100−x (46≤x≤70) alloys are studied.•Atomic packing efficiency strongly correlates with the glass-forming ability (GFA).•Full icosahedra (<0,0,12,0>) alone cannot explain the compositional dependence of GFA.•Population of the defected icosahedra (<0,2,8,2>) is important.
Bimetallic MOFs offer many advantageous properties rather than monometallic MOFs useful for variety of applications including energy storage and conversion, catalysis, gas separation, sensing, etc. ...Desired morphology with precise control of crystal size is of utmost importance for specific applications. Microfluidics-incorporated continuous synthesis is demonstrated for bimetallic ZIF-8/67 exhibiting significant nanocrystallinity, porosity and surface area. The microfluidic approach of synthesizing MOF is found very time-efficient in comparison with the conventional techniques. Bimetallic ZIF-8/67 samples were synthesized at different reaction conditions, without adding capping agents and modulators, followed by sophisticated characterization techniques including powder X-ray diffraction, field emission scanning electron microscopy, transmission electron microscopy, energy-dispersive spectroscopy, X-ray photoelectron spectroscopy, thermogravimetric analysis, Brunauer–Emmett–Teller analysis and Fourier transform infrared spectroscopy.
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•Langmuir isotherms of monolayer of casein & whey protein macromolecules are evaluated.•Surface pressure was altered due to intermolecular interaction of ...proteins.•Electrical-equivalent resistances have been identified for protein samples using EIS.
Proteins are very important biological macromolecules, specific in their functions essential for many biological activities. Proteins are among the most vital components of all living matters with thousands of different types, and they are very specific in their nature which makes them important for usage in many biotechnological, biomedical, and food processing applications. Langmuir monolayer studies provide the characteristics of monolayer at the air-liquid interface. Langmuir monolayer of protein is affected by the molecular weight, macromolecular structure, denaturation and its purity. The interaction of the protein with other molecules greatly affects the behaviour of monolayer. Coconut oil layer at the air-water interface was prepared with different sub-phases including casein protein and whey protein. Wilhelmy plate measurement technique has been used to measure the surface pressure of the monolayer at the air-liquid interface. Experiments were carried out to study the stability using electrochemical impedance measurements. The electrostatic forces dominated the coconut oil - protein interaction, and the interface of macromolecules were controlled by expansion and compression. The macromolecules were adsorbed with a preferential orientation at the interface, and the stability of colloidal dispersions was governed by the intermolecular interactions. The stability using electrochemical impedance spectroscopy on the selected protein macromolecules along with other analysis were performed by varying various parameters.
Zeolitic imidazolate framework (ZIF) materials are thermally and chemically stable, and suitable for many possible applications, including chemical sensors, gas separation, energy storage, catalysis, ...etc. However, the conventional synthesis techniques of ZIFs need to be revisited to make them time-efficient and cost-effective with better process control. Here we show the potential of microfluidics for the synthesis of ZIF, resulting in improved porosity, surface morphology and stability. Four distinct operating conditions were used to synthesize ZIF-67 metal–organic framework, viz. sonication at room temperature, without sonication at room temperature, 70 °C, and 120 °C, using a fully continuous microfluidic technique incorporating a T-type micromixer connected to a helical microfluidic flow reactor (HMFR). ZIF-67 is synthesized in methanol at a constant metal salt/ligand ratio of 1:8 without adding modulators such as capping agents and surfactants. We used a T-micromixer coupled with a helically wound microfluidic tubing for the first time to synthesize the crystalline ZIF-67 resulting in synthesis of high quality ZIF through the continuous and time-effective processing route. The samples were characterized using FESEM, TEM, XPS, XRD, BET, TGA and FTIR which showed remarkable characteristics of ZIF-67 useful for many applications.
Abstract Modeling of the red blood cell (RBC) shape is an integral part of the experimental and computer simulation investigations of light scattering by these cells for fundamental studies as well ...as diagnostic applications in techniques like cytometry and quantitative phase imaging. In the present work, a comprehensive study of the geometrical characterization of healthy human RBCs using digital holographic microscopy (DHM) and six frequently employed parametric shape models is reported. It is shown that the comparison of the optical phase profiles, and the thickness profiles given by the models with the DHM results gives a better judgment of the appropriateness of the parametric shape models. It is also shown that the RBC parametric models offer a simpler solution to the refractive index-thickness decoupling problem in QPI methods. Results of geometrical characterization of 500 healthy RBCs in terms of volume, surface area (SA), and sphericity index (SI) led to the classification of the parametric models in two categories based on the nature of variation of these quantities with the cell diameter. In light of the variability of the healthy RBC shapes, our findings suggest that the parametric models exhibiting a negative correlation between the SI and the cell diameter would provide more reliable estimates of the RBC parameters in diagnostic applications. Statistical distributions and descriptive statistics of the RBC volume, SA and SI serve as a guide for the assessment of the capability of the studied parametric models to give a reliable account of the variability of the healthy RBC shape and size.
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