Innovative Method for Water-in-Oil Emulsion Treatment Using Atmospheric Nonthermal-Plasma Technology.

The field of plasma-liquid interactions is rapidly growing, with increasing publications across applications. While plasma's interactions with water and oil have been researched, there is a notable gap in the study of plasma-emulsion interactions and their practical applications. Investigating plasma-emulsion interactions offers a dual advantage, as demonstrated in this study, as it is applicable to both water/oil separation and emulsion stabilization processes. This study introduces a groundbreaking approach utilizing the fountain dielectric barrier discharge (FDBD) plasma reactor. The reactor exposes a model emulsion to different plasma gases, such as air, nitrogen, argon, and ammonia, along with varying parameters of plasma input voltage and treatment time. Consequently, due to demulsification, the emulsion segregates into distinct water and oil phases. Remarkably, the results demonstrate that short-term plasma treatment leads to the separation of over 99% of emulsified water. However, prolonged exposure to plasma for around 7 min reveals a decrease in the volume of free-separated water, implying the occurrence of stable emulsion formation instead of further demulsification. To optimize experimental conditions for compliance with regulatory requirements, the study employs the response surface methodology (RSM). Adapting pH and separation contours in three-dimensional (3D) RSM plots shows that achieving higher separation is likely associated with higher pH levels in air, nitrogen, and argon plasmas. Notably, the plasma treatment involving ammonia gas elevates the pH level and yields the highest degree of separation compared with air, nitrogen, or argon plasmas.

Developing a facile graphitic carbon nitride (g-C3N4)-coated stainless steel mesh with different superhydrophilic/underwater superoleophobic and superoleophilic behavior for oil-water separation.

There is an increasing demand for the development of inexpensive and effective approaches for the oil-water separation due to the global concern in oil industries. The present study was conducted to fabricate graphitic carbon nitride/thermoplastic polyurethane (g-C3N4/TPU)-coated stainless steel meshes via the dip-coating method to investigate the capability of g-C3N4 nanosheets (CN-NS) in oil-water separation. CN-NS was synthesized using the polycondensation process followed by exfoliation with Hummer's method. We studied the effect of TPU and CN-NS concentration on wettability behavior to obtain an optimized coating solution. CN-NS-coated mesh showed superoleophilic/hydrophobic behavior at CN-NS:TPU ratio of 50:50, and it efficiently passed oil from the emulsified water-in-oil mixture (with 50 wt.% oil) with the efficiency of 99%. The wettability behavior of superhydrophilic/underwater superoleophobic was also obtained at CN-NS:TPU ratio of 80:20, and it was able to separate water from the emulsified water-in-oil mixture with the efficiency of 79% under gravity. Both filters were able to separate free water and oil mixtures with flux and efficiency of 6114 L.m-2.h-1 and ~ 99.99%, respectively. The mechanism of wettability behavior of the coating is mainly related to the functional groups on the edge of g-C3N4-NS, thus increasing the hydrophilic properties of the surface. In addition, the micro-nano hierarchical structure of the surface coating improves its roughness due to the presence of CN-NS, which is effectively embedded into the hydrophilic TPU. More importantly, commercially available TPU chemical and simple fabrication of g-C3N4 from an inexpensive precursor make the method reported herein as a significant alternative for large-scale application.

Mechanistic insights into the inhibitory activity of FDA approved ivermectin against SARS-CoV-2: old drug with new implications.

The novel corona virus (Covid-19) has become a great challenge worldwide since 2019, as no drug has been reported yet. Different clinical trials are still under way. Among them is Ivermectin (IVM), an FDA approved drug which was recently reported as a successful candidate to reduce SARS-CoV-2 viral load by inhibiting Importin-α1 (IMP-α1) protein which subsequently affects nuclear transport of viral proteins but its basic binding mode and inhibitory mechanism is unknown. Therefore, we aimed to explore the inhibitory mechanism and binding mode of IVM with IMP-α1 via different computational methods. Initially, comparative docking of IVM was performed against two different binding sites (Nuclear Localization Signal (NLS) major and minor sites) of IMP-α1 to predict the probable binding mode of IVM. Then, classical MD simulation was performed (IVM/NLS-Major site and IVM/NLS-Minor site), to predict its comparative stability dynamics and probable inhibitory mechanism. The stability dynamics and biophysical analysis of both sites highlighted the stable binding of IVM within NLS-Minor site by establishing and maintaining more hydrophobic contacts with crucial residues, required for IMP-α1 inhibition which were not observed in NLS-major site. Altogether, these results recommended the worth of IVM as a possible drug to limit the SARS-CoV-2 viral load and consequently reduces its progression.Communicated by Ramaswamy H. Sarma.

Protonation states at different pH, conformational changes and impact of glycosylation in synapsin Ia.

Synapsin I (SynI) is the most abundant brain phosphoprotein present at presynaptic terminals that regulates neurotransmitter release, clustering of synaptic vesicles (SVs) at active zones, and stimulates synaptogenesis and neurite outgrowth. Earlier studies have established that SynI displays pH-dependent tethering of SVs to actin filaments and exhibits a maximum binding around neutral pH, however, the effect of pH shift from acidic to basic on the conformational stability of SynI has not been explored yet. Another important aspect of SynIa is its O-GlcNAcylation (O-GlcNac) at the Thr87 position, which is responsible for the positive regulation of synaptic plasticity linked to learning and memory in mice. Furthermore, reduced levels of O-GlcNAc have been observed in Alzheimer's disease, suggesting a possible link to deficits in synaptic plasticity. In this study, the effect of pH and glycosylation on the structure and functional stability of SynIa is determined through molecular dynamics (MD) simulation approach. The 3D structure of SynIa was established via threading-based homology modeling methods. It was observed that the structure of SynIa adopts extended conformational changes as the pH shifts from acidic to basic, resulting in a compact conformation at pH 8.0. Moreover, the results obtained by comparing the glycosylated and unglycosylated protein indicated that the glycan moiety imparts stability to the protein by forming intramolecular hydrogen bond interactions with the protein residues. The results indicate that although O-GlcNAc moieties do not induce a significant change in SynIa structure they minimize protein dynamics, likely leading to enhanced protein stability.