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Respiratory infections by RNA viruses are one of the major burdens on global health and economy. Viruses like influenza or coronaviruses can be transmitted through respiratory droplets or contaminated surfaces. An effective antiviral coating can decrease the viability of the virus particles in our surroundings significantly, hence reducing their transmission rate. Here, we have screened a series of nanoparticles and their composites for antiviral activity using a nanoluciferase-based highly sensitive influenza A reporter virus. We have identified copper–graphene (Cu–Gr) nanocomposite as a material with strong antiviral activity. Extensive material and biological characterization of the nanocomposite suggested a unique metal oxide-embedded graphene sheet architecture that can inactivate the virion particles within 30 min of preincubation and subsequently interferes with the entry of these virion particles into the host cell. This ultimately results in reduced viral gene expression, replication and production of progeny virus particles, and thereby slowing down of the overall pace of progression of infection. Using poly­(vinyl alcohol) (PVA) as a capping agent, we have been able to generate a Cu–Gr nanocomposite-based highly transparent coating that retains its original antiviral activity in the solid form and hence can be potentially implemented on a wide variety of surfaces to minimize the transmission of respiratory virus infections.

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Bacterial infections being sporadic and uncontrollable demands an urgent paradigm shift in the development of novel antibacterial agents. This work involves the fabrication of Cu 2 O nanopetals over copper foil that show superlative antibacterial and superhydrophobic properties. A superhydrophobic surface has been fabricated using the electrochemical deposition (ECD) method. Here, it is aimed to establish the superior antibacterial activity as an outcome of the inherent superhydrophobic property of the as-fabricated nanostructures. The present study finds that the elevated value of the water contact angle (154 ± 0.6°) does not allow proper bacterial adhesion, and it is immune from the possibility of biofouling. Specifically, two kinds of bacterial strains have been tested and the time response of the antibacterial activity has been studied over a period of 12 h, taking DH5α Escherichia coli as a Gram-negative model and Bacillus subtilis 168 as a Gram-positive model. Higher antibacterial effects were observed for the Gram-negative model (E. coli) owing to its simplistic cell wall structure which facilitates the easy diffusion of Cu + ions into the bacterial membrane. The simplicity of the developed method of fabrication along with the superlative superhydrophobic nature and excellent antibacterial property of the material, owing to its synergistic biophysical and biochemical modes of biocidal action, establishes its viability in many applications.

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Xylanases are used in various agricultural and industrial applications. A synthetic, modified, codonoptimized xylanase gene (XynZ) from Clostridium thermocellum was expressed in transgenic tobacco plants. The coding sequence of XynZ was placed between the modified Mirabilis mosaic virus full-length transcript promoter with duplicated enhancer domains and the terminator sequence from the rbcSE9 gene. Three constructs were developed to evaluate XynZ expression levels by targeting gene products into the cytosol, intercellular space, or endoplasmic reticulum in transgenic plants. These chimeric genes, expressed in transgenic tobacco (Nicotiana tabacum cv. Samsun NN) were stably inherited in successive plant generations (R0, R1, and R2 progeny; primary, second, and third generation) as shown by molecular characterization (RT-PCR and qRT-PCR) and enzymatic assays. A Western blot analysis of plant extracts showed presence of a polypeptide of the expected size that cross-reacted with xylanase-specific antibodies. Transgenic plants were morphologically similar to wild-type plants and showed no deleterious effect due to transgene expression. The expressed xylanase was heat-stable, having optimum activity between 55°C and 75°C over a pH range of 5 to 5.6.

Insertion of 2:1 organo-modified phyllosilicate tactoids into rheologically tough thermoplastics has extraordinary potential candidate in oxygen permeability and microstructural toughening. Herein, two commercially abundant clays have been taken for improvement of the thermoplastic's gas barrier property in reasonably low loading. The cause of low loading has been accounted to the usage of maleated polyethylene (MA-g-PE) during the melt mixing tenure. The optimized nanocomposite compression molded film has been tested against uniaxial stretching, which showed a negligible change in the residual permanent set with sacrificing the elongation at break feature. Moreover, nanoindentation was also performed to get the hardness of the sample surface. The flow behavior of the nanocomposites showed thixotropic likely with increasing the frequency. Oxygen transmission rate (OTR) has significantly decreased for tallow amine-modified nanoclay system (cloisite 15A) in compar

Luminescent carbon dots, a newcomer in the domain of nanolights and nanomaterials have been studied extensively since past few years due to their fascinating properties of sensor design, biocompatibility, cell tracking, or fluorescence based live cell assays, medical diagnosis, photocatalysts, and also being potential building blocks for nanodevices. In this study, one‐pot green synthesis of water dispersible fluorescent carbon dots have been synthesized by using roasted gram shells. The structural and optical properties of the as‐prepared carbon dots are characterized by TEM, FTIR, UV‐vis absorption, photoluminescence spectra. The carbon dots showed greenish blue fluorescence under UV irradiation, excitation dependent emission, upconverted emission, high pH tolerance, and good biocompatibility. The carbon dots labeled Escherichia coli (E. coli) unveiled multicolor emission behavior under different excitation wavelength. These carbon dots showed their superiority with respect to commercially available synthetic dyes which have severe limitations including photobleaching effect, high cost, etc. The incorporation of carbon dots in the bacterial culture medium does not show any kind of growth delay of the bacterium up to 400 mg mL−1. The goal is to establish this carbon dots in bio‐labeling assay with its physicochemical features (small particle size, high luminescence efficiency, good biocompatibility, low toxicity) against various environments such as wide range of pH, high ionic medium. Concisely, this work bestows an innovative aspect to the commercialization of carbon dots as a potent alternative to synthetic organic dyes for multicolor emitting probes for cell‐labeling gram negative bacteria E. coli.