Self-assembly of bovine serum albumin (BSA)-dextran bio-nanoconjugate: structural, antioxidant and in vitro wound healing studies.

Glycation of proteins is often considered as a method to improve their functional properties for promising applications in wound healing. Furthermore, a marked increase in percentage of radical scavenging activity of the conjugates makes it an effective antioxidant synthetic strategy. A simple conjugation process was employed to develop bovine serum albumin-dextran conjugates (BSA-dextran) using Maillard reaction. Higher electrophoretic mobility and surface charge in the prepared conjugates was observed in native PAGE electrophoresis and zeta potential. Moreover, the fluorescence, FTIR and Raman analysis of the BSA-dextran conjugates shows significant shift in the fluorescence and wavelength as a consequence of conjugate formation. In vitro wound healing assay showed increased cell proliferation and migration effect. These finding suggests that BSA-dextran conjugate could open up a new practical way for exploration in the area of wound healing.

Correction: Self-assembly of bovine serum albumin (BSA)-dextran bio-nanoconjugate: structural, antioxidant and in vitro wound healing studies.

[This corrects the article DOI: 10.1039/D0RA09301G.].

Hybrid chitosan-ZnO nanoparticles coated with a sonochemical technique on silk fibroin-PVA composite film: A synergistic antibacterial activity.

The hybrid chitosan-ZnO nanoparticles (C@ZnO NPs) are synthesized and coated on Silk fibroin-polyvinyl alcohol (SF-PVA) composite film by a sonochemical coating process. These are systematically studied for their synergistic antibacterial activity and reported. The coated composite films show the excellent antibacterial activity against Gram-positive and Gram-negative bacteria. The composite films are characterized by using X-ray diffraction (XRD), Fourier transform infrared spectroscopy (FTIR), and Scanning Electron Microscopy (SEM) studies. The specific surface area and porosity are studied by Brunauer-Emmett-Teller (BET) analysis under nitrogen gas adsorption. The swelling degree, mechanical property and cell viability study of coated and uncoated composite films are investigated. The results showed that the specific surface area, porosity, swelling degree, and mechanical property of coated composite films increased with increasing the concentrations of C@ZnO NPs on SF-PVA composite film. Cell viability study confirmed the cytocompatible nature of all the C@ZnO NPs coated composite films. Thus, obtained properties of composite films reveal the potential of this material which can be used as antibacterial wound dressing applications.

Surface-Modified Cobalt Ferrite Nanoparticles for Rapid Capture, Detection, and Removal of Pathogens: a Potential Material for Water Purification.

Enteric infections resulting from the consumption of contaminated drinking water, inadequate supply of water for personal hygiene, and poor sanitation take a heavy toll worldwide, and developing countries are the major sufferers. Consumption of microbiologically contaminated water leads to diseases such as amoebiasis, cholera, shigellosis, typhoid, and viral infections leading to gastroenteritis and hepatitis B. The present investigation deals with the development of effective method to capture and eliminate microbial contamination of water and improve the quality of water and thus decreasing the contaminated waterborne infections. Over the last decade, numerous biomedical applications have emerged for magnetic nanoparticles (MNPs) specifically iron oxide nanoparticles. For the first time, we have explored functionalized cobalt ferrite nanoparticles (NPs) for capture and detection of pathogens. The captured bacterial were separated by using simple magnet. To begin with, the prepared NPs were confirmed for biocompatibility study and further used for their ability to detect the bacteria in solution. For this, standard bacterial concentrations were prepared and used to confirm the ability of these particles to capture and detect the bacteria. The effect of particle concentration, time, and pH has been studied, and the respective results have been discussed. It is observed that the presence of amine group on the surface of NPs shows nonspecific affinity and capability to capture Escherichia coli and Staphylococcus aureus. The possible underlying mechanism is discussed in the present manuscript. Based upon this, the present material can be considered for large-scale bacteria capture in water purification application.

Photoinactivation of bacteria by using Fe-doped TiO2-MWCNTs nanocomposites.

In this study, nanocomposites of Fe-doped TiO2 with multi-walled carbon nanotubes (0.1- 0.5 wt. %) were prepared by using sol-gel method. The structural and morphological analysis were carried out with using X-ray diffraction pattern and transmission electron microscopy, which confirm the presence of pure anatase phase and particle sizes in the range 15-20 nm. X-ray photoelectron spectroscopy was used to determine the surface compositions of the nanocomposites. UV-vis diffuse reflectance spectra confirm redshift in the optical absorption edge of nanocomposites with increasing amount of multi-walled carbon nanotubes. Nanocomposites show photoinactivation against gram-positive Bacillus subtilis as well as gram-negative Pseudomonas aeruginosa. Fe-TiO2-multi-walled carbon nanotubes (0.5 wt. %) nanocomposites show higher photoinactivation capability as compared with other nanocomposites. The photoluminescence study reveals that the Fe-TiO2-multi-walled carbon nanotubes nanocomposites are capable to generate higher rate of reactive oxygen species species than that of other nanocomposites. Our experimental results demonstrated that the Fe-TiO2-multi-walled carbon nanotubes nanocomposites act as efficient antibacterial agents against a wide range of microorganisms to prevent and control the persistence and spreading of bacterial infections.

Enhanced photocatalytic inactivation of bacteria on Fe-containing TiO2 nanoparticles under fluorescent light.

In this paper, the photocatalytic activity of Fe-TiO2 nanoparticles (NPs) under fluorescent light was studied using Escherichia coli and Staphylococcus aureus. Fe-TiO2 NPs were synthesized using a sol-gel method and characterized with X-ray diffraction (XRD), X-ray photoelectron spectroscopy (XPS), UV-visible diffuse reflectance spectroscopy (UV-vis DRS) and transmission electron microscopy. The efficiency of photocatalytic inactivation towards E. coli was studied under different physicochemical parameters. The photocatalytic inactivation rate increased with increasing Fe content in TiO2 NPs and the highest inactivation was achieved for 3.0 mol% Fe-TiO2 NPs under fluorescent light. These results demonstrate that the presence of an optimum concentration of Fe in TiO2 matrix enhances the photocatalytic inactivation of TiO2 NPs under fluorescent light.

Innovative Developments in Bacterial Detection with Magnetic Nanoparticles.

It has been seen from the last decade that many bacterial strains are becoming insensitive to conventional detection techniques and it has its own limitations. Current developments in nanoscience and nanotechnology have expanded the ability to design and construct nanomaterials with targeting, therapeutic, and diagnostic functions. These multifunctional nanomaterials have attracted researchers, to be used as the promising tool for selective bacterial sensing applications. An important advantage of using magnetic nanoparticles to capture bacteria is the simple separation of bacteria from biological samples using magnets. This review includes significance of magnetic nanoparticles in bacterial detection. Relevant to topic, properties, designing strategies for magnetic nanoparticle, and innovative techniques used for detection are discussed. This review provides the readers how magnetic properties of nanoparticles can be utilized systematically for bacterial identification.