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The growth-associated metabolites are produced during the exponential phase; however, this phase terminates due to substrate depletion or product inhibition. In the present study, a semicontinuous mode with a fill-and-draw strategy was applied to extend the exponential phase of the biosurfactant production to overcome the product inhibition and in turn, enhance the yield. Bioreactor studies were performed in batch mode, followed by the semicontinuous operation. A potential biosurfactant producer Bacillus subtilis RSL2 was used in this study at the previously optimized conditions of pH 6.6, temperature 41 °C and 5% (w/v) of molasses. A better mass transfer was achieved in the bioreactor as compared to the shake flask study. In the batch bioreactor study, 90% of sugar was utilized with simultaneous 13.7 g L

Hydroxyapatite (HAp) is one of the most studied biomaterials for orthopaedic applications, yet its commercialization holds in a few of the lags, such as non-antibacterial activity and target deficiency. In this context, we aimed to design a biphasic nanoassembly of Ferric-HAp-Zincite (ZFHAp) via a one-step co-precipitation method. Ferric-HAp obtained Ca9·333Fe1·167(PO4)7 phase in all the samples, and the secondary phases such as Ca9Fe(PO4)7 and Ca28·8Fe3·2(PO4)21O0.5 were governed by the Fe dopant concentration. Along with ferric-HAp, zincite phases were present in all the samples depending on the concentration of Zn precursor. The synthesized ZFHAp samples were hexagonal in structure with size

We report the tuneable spin angular momentum transfer (spin pumping) from Co60Fe20B20 (CFB) amorphous alloy into the Ta heavy metal nanolayers. All the films are grown on Si (100) substrate at room temperature using ion-beam sputtering technique. Structural studies reveal that the grown Ta films over amorphous CFB are crystalline even at ultrathin regime. The bilayers possess very low interface roughness (i.e., follows ballistic spin transport) in two series of CFB (4nm)/Ta (0-10nm) and CFB(6nm)/Ta (0-10nm) bilayers, which is characteristic of normal spin pumping. However, the anomalous behaviour has been observed for CFB (8nm)/Ta (0-10nm) bilayer series where the spin current generated in Ta with the thicker CFB behaves oppositely. The results demonstrate the strong dependence of ferromagnet thickness on the spin pumping into the Ta nanolayers. This study paves the way to choose suitable ferromagnetic layer thickness for spin current induced switching applications in spintronics.

The preferable mechanical properties of Mg alloys along with excellent compatibility with human bone have established their applicability as implant biomaterials. However, a higher corrosion/degradation rate of Mg alloys in body fluids limits its biomedical applications. In this direction, surface modification and coating are explored as appropriate strategies to mode the degradation rate of Mg alloys. The constituents of bioactive glass (BG) provide strength, bio-inertness and bone bonding capability. Hence, researchers have explored the coating of BG on Mg alloys and investigated chemical, mechanical and biological properties of the coated alloys. In this review, we have made an attempt to compile the literature works done on the coating of BG on Mg alloys and its features. Underlying interfacial aspects of the coated substrates towards the degradation behavior are highlighted. The way forward to further improve the coating characteristics of BG coated Mg alloys are remarked.

The outermost surfaces of Personal Protective Equipments (PPEs) interact with virus surface-protein as the first step during its transmission from aerosols and contacting surfaces, which can be tun...

Microbial surface attachment negatively impacts a wide range of devices from water purification membranes to biomedical implants. Mimics of antimicrobial peptides (AMPs) constituted from poly(N‐substituted glycine) „peptoids“ are of great interest as they resist proteolysis and can inhibit a wide spectrum of microbes. We investigate how terminal modification of a peptoid AMP‐mimic and its surface immobilization affect antimicrobial activity. We also demonstrate a convenient surface modification strategy for enabling alkyne–azide „click“ coupling on amino‐functionalized surfaces. Our results verified that the N‐ and C‐terminal peptoid structures are not required for antimicrobial activity. Moreover, our peptoid immobilization density and choice of PEG tether resulted in a „volumetric“ spatial separation between AMPs that, compared to past studies, enabled the highest AMP surface activity relative to bacterial attachment. Our analysis suggests the importance of spatial flexibility for membrane activity and that AMP separation may be a controlling parameter for optimizing surface anti‐biofouling., Efficient anti‐biofouling: We show that an archetypical antimicrobial peptoid could retain high activity even with terminal modifications. Immobilization by alkyne–azide „click“ coupling on one‐step modified amino‐surfaces was demonstrated. Appropriate spatial separation between immobilized peptoids, rather than increasing surface density, was found to promote both resistance against bacterial attachment and AMP surface activity.

The article investigates electrically active ceramic composite of $$\mathrm{Ca}_{10}(\mathrm{PO}_4)_6(\mathrm{OH})_2$$ Ca 10 ( PO 4 ) 6 ( OH ) 2 (HAP) and $$\mathrm{Ba}_{0.5}\mathrm{Sr}_{0.5}\mathrm{TiO}_{3}$$ Ba 0.5 Sr 0.5 TiO 3 (BST) for biomedical applications. The study is a systematic blend of the materials science aspect of composites with a special focus on the dielectric and biological properties and their relationships. The article emphasized primarily extracting the dielectric constant ($$\epsilon _r)$$ ϵ r ) of the specimens (that lay in the range of 3–65) and related them to microstructural properties like the grain size and at.% of BST. A broad outlook on the importance of $$\epsilon _r$$ ϵ r in determining the suitability of bioceramics for clinical applications is presented. Bioactivity analysis of the specimens led to probing the surface charges (that were negative), and it was found crucial to the growth of dense apatite layers. Furthermore, the cytocompatibility of the specimens displayed cell viability above 100% for Day 1, which increased substantially for Day 3. To reveal other biological properties of the composites, protein adsorption studies using bovine serum albumin (BSA) and fetal bovine serum (FBS) was carried out. Electrostatic interactions govern the adsorption, and the mathematical dependence on surface charges is linear. The protein adsorption is also linearly correlated with the $$\epsilon _r$$ ϵ r , intrinsic to the biomaterials. We delve deeper into protein–biomaterials interactions by considering the evolution of the secondary structure of BSA adsorbed into the specimens. Based on the investigations, 20 at.% HAP–80 at.% BST (20H–80B) was established as a suitable composite comprising the desired features of HAP and BST. Such explorations of electrical and biological properties are interesting for modulating the behavior of bioceramic composites. The results project the suitability of 20H–80B for designing electrically active smart scaffolds for the proposed biomedical applications and are expected to incite further clinical trials.

Exchange bias (EB) of magnetic nanoparticles (MNPs) in the nanoscale regime has been extensively studied by researchers, which have opened up a novel approach in tuning the magnetic anisotropy properties of magnetic nanoparticles (MNPs) in prospective application of biomedical research such as magnetic hyperthermia. In this work, we report a comparative study on the effect of magnetic EB of normal and inverted core@shell (CS) nanostructures and its influence on the heating efficiency by synthesizing Antiferromagnetic (AFM) NiO (N) and Ferrimagnetic (FiM) Fe

The aggregation of therapeutic proteins is potentially encountered during various steps such as bioprocessing, formulation, storage, transportation and administration. The aggregation results in irreversible drug loss and also leads to an increase in the risk of immunogenicity. The aggregated proteins have also been associated with various protein deposition diseases like amyloidosis. Various physicochemical factors like pH, temperature, salt concentrations, ionic strength, shear and surface affect the stability of proteins. Interestingly, therapeutic proteins simultaneously experience these physical, chemical and mechanical stresses during upstream, downstream and storage processes. The above physicochemical factors are reported to induce the unfolding and aggregation of proteins. The mechanistic insights of this complex aggregation behavior may allow devising strategies to limit/restrict this unwanted phenomenon. This review intends to undertake systematic descriptions of the key physicochemical factors in upstream and downstream bioprocesses and correlating their implications with the unfolding and aggregation of therapeutic proteins. The present review highlights the impacts of environmental, chemical and mechanical factors of the bioprocessing on the stability/aggregation of therapeutic proteins. The present review offers insight into this important phenomenon, which will be helpful for real-world challenges in the bioprocess and bio-therapeutic industries.

Exchange bias (EB) of magnetic nanoparticles (MNPs) in the nanoscale regime has been extensively studied by researchers, which have opened up a novel approach in tuning the magnetic anisotropy properties of magnetic nanoparticles (MNPs) in prospective application of biomedical research such as magnetic hyperthermia. In this work, we report a comparative study on the effect of magnetic EB of normal and inverted core@shell (CS) nanostructures and its influence on the heating efficiency by synthesizing Antiferromagnetic (AFM) NiO (N) and Ferrimagnetic (FiM) Fe3O4 (F). The formation of CS structures for both systems is clearly authenticated by XRD and HRTEM analyses. The magnetic properties were extensively studied by Vibrating Sample Magnetometer (VSM). We reported that the inverted CS NiO@Fe3O4 (NF) MNPs have shown a greater EB owing to higher uncompensated spins at the interface of the AFM, in comparison to the normal CS Fe3O4@NiO (FN) MNPs. Both the CS systems have shown higher SAR values in comparison to the single-phased F owing to the EB coupling at the interface. However, the higher surface anisotropy of F shell with more EB field for NF enhanced the SAR value as compared to FN system. The EB coupling is hindered at higher concentrations of NF MNPs because of the enhanced dipolar interactions (agglomeration of nanoparticles). Both the CS systems reach to the hyperthermia temperature within 10 min. The cyto-compatibility analysis resulted in the excellent cell viability (> 75%) for 3 days in the presence of the synthesized NPs upto 1 mg/ml. These observations endorsed the suitability of CS nanoassemblies for magnetic fluid hyperthermia applications.

Rapid transmission of the severe acute respiratory syndrome coronavirus 2 has affected the whole world and forced it to a halt (lockdown). A fast and label-free detection method for the novel coronavirus needs to be developed along with the existing enzyme-linked immunosorbent assay (ELISA) and reverse transcription polymerase chain reaction (RT-PCR)-based methods.In this report, biophysical aspects of severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2) spike glycoprotein are outlined based on its recent reported electron microscopy structure. Protein binding sites are analyzed theoretically, which consisted of hydrophobic and positive charged amino acid residues. Different strategies to form mixed self-assembled monolayers (SAMs) of hydrophobic (CHImplementation of the engineered surfaces in quartz crystal microbalance (QCM)-based detection techniques for the diagnosis of the novel coronavirus from oral swab samples is highlighted. The proposed strategy can be explored for the label-free and real-time detection with sensitivity up to ng level. These engineered surfaces can be reused after desorption.

Poly(N-substituted glycine) “peptoids” are an interesting class of peptidomimics that can resist proteolysis and mimic naturally found antimicrobial peptides (AMPs), which exhibit wide spectrum activity against bacteria. This work investigates the possibility of modifying peptoid AMP mimics (AMPMs) with aliphatic lipid “tails” to generate “lipopeptoids” that can assemble into micellar nanostructures, and evaluates their antimicrobial activities. Two families of AMPMs with different distributions of hydrophobic and cationic residues were employed—one with a uniform repeating amphiphilicity, the other with a surfactant-like head-to-tail amphiphilicity. To further evaluate the interplay between self-assembly and activity, the lipopeptoids were variously modified at the AMPM chain ends with a diethylene glycol (EG2) and/or a cationic group (Nlys-Nlys dipeptoid) to adjust amphiphilicity and chain flexibility. Self-assembly was investigated by critical aggregation concentration (CAC) fluorescence assays and dynamiclight scattering (DLS). The structure of a key species was also verified by small-angle X-ray scattering (SAXS) and cryo-electron microscopy (cryo-EM). To screen for antibacterial properties, we measured the minimum inhibitory concentrations (MIC) against S. aureus, E. coli, and P. aeruginosa. We found that certain combinations of lipid tail and AMPM sequences exhibit increased antibacterial activity (i.e., decreased MICs). Perhaps counter-intuitively, we were particularly interested in increased MICs in combination with low CACs. Concealing antimicrobial interactions due to packing of AMPMs in nano-assemblies could pave the way to AMPMs that may be “inert” even if unintentionally released and prevent microbes from gaining resistance to the lipopeptoids. Overall, incorporation of EG2 significantly improved lipopeptoids packing while the hydrophobic tail length was found to have a major influence over the MIC. One particular sequence, which we named C15-EG2-(kss)4, exhibited a very low CAC of 34 μM (0.0075 wt.%) and a significantly increased MIC above values for the unmodified AMPM. With the sequence design trends uncovered from this study, future work will focus on discovering more species such as C15-EG2-(kss)4 and on investigating release mechanisms and the potency of the released lipopeptoids.

In the present study, bimetallic aluminium doped zinc oxide (AZO) nano-assemblies were synthesized for heavy metal removal and disinfection of wastewater. These bimetallic nanoparticles (NPs) were prepared by a simple co-precipitation method and characterized using field emission transmission electron microscopy (FETEM), X-ray diffraction (XRD), Fourier transform infrared spectroscopy (FT-IR), Brunauer–Emmett–Teller (BET), a Litesizer, and energy dispersive X-ray spectroscopy (EDS). The AZO NPs was tested for lead removal at various environmental conditions and optimized at pH 4 and 25 °C. The kinetic data were well fitted to the pseudo-second-order model and the process consisted of both surface adsorption and intraparticle diffusion. Al doping enhanced the surface charge of AZO NPs four fold as compared to ZnO, which improved colloidal stability and contributed towards its reusability. AZO NPs exhibited excellent removal efficiency of 86% over three adsorption-desorption cycles. The adsorption was found to be an exothermic and physicochemical process. The prepared AZO NPs were also used to treat a real wastewater sample and found to effectively remove Pb(II) and kill all the bacteria present.

Protein aggregation is induced by various environmental or external factors and associated with various neurodegenerative diseases. Among various external factors, shear stress is inevitable for both in vivo and in vitro applications of proteins. In this study, Aβ (1–40) peptide, a derivative of the amyloid precursor protein, was subjected to constant (300, 500, 700 s−1) and varying (ramp) shear in a parallel plate geometry to explore the implications of shear in terms of macro (viscosity) and micro (secondary structure, morphology) characteristics. Aβ (1–40) solution followed a shear thickening flow behaviour with performance index value ‘n’ of 2.12. The fibrillation process resulting from the shear force was evaluated in terms of dissipation energy, which was found to exceed the free energy of unfolding. This resulted in the formation of β-sheet rich structures, which were confirmed by CD and FTIR analyses and enhanced Th-T fluorescence. The apparent rate of aggregation (k) was found to increase with the shear rate, and inversely related to the solution viscosity. The maximum k value was 0.21 ± 0.3 min−1 at 700 s−1. The molecular weights of aggregates were determined using gel filtration, which were proportionally related to the solution viscosity. The average molecular weights were estimated to be 70, 62 and 52 KDa for samples sheared at 300, 500 and 700 s−1, respectively. The present study has deciphered the interplay of viscosity, a fluid property, with the aggregation process and its corresponding change in the secondary structures of the peptide. These findings provide useful insights for understanding various proteopathies under shear force. Communicated by Ramaswamy H. Sarma

In this study, the development of uniaxial magnetic anisotropy (UMA) and out-of-plane coercivity (Hc┴) in W/Co20Fe60B20(CoFeB)/W structures by tuning the annealing temperature (TA) such as 300°C, 400°C and 500°C were achieved. For 400°C film, W and CoFeB interfaces play a major role in achieving the large Hc┴. Furthermore, the observation of large Hc┴ was found to be significantly induced by the interface on the two sides of CoFeB layer. The two-fold UMA strongly is stabilized in W/CoFeB/W trilayers up to 500°C. A maximum in-plane uniaxial anisotropy energy density (Ku) was observed for the 500°C annealed films, which is accompanied by the dominance of Hc┴ owing to the over-oxidation and/or occurrence of inter-diffusion across the interfaces. The oxidation and relieving of boron atoms in the CoFeB at higher annealing temperatures were confirmed by X-ray photoelectron spectroscopy (XPS). The control over the interface shared between the W and CoFeB is concluded to be essential in order to alter the strength of magnetic anisotropy. Hence, an investigation on W/CoFeB/W structures could be very beneficial for the modern Spin-Orbit Torque (SOT) based data storage applications and this inspires relevant research work to widen magnetic systems.

We report a novel, yet simple, DC non-transferred thermal plasma torch assisted, green, plasma-chemical reactor configuration, for high-rate synthesis of tungsten-oxide nanomaterials, up to two hundred grams per hour. An expanded argon/oxygen plasma beam is produced with a collimated, frozen structure, which interacts uniformly and in a controlled manner, over a large area of the remotely placed, tungsten target, to produce superfine particles in bulk amounts and without mixed with large aggregates. The target surface gets oxidized to form volatile tungsten-oxide, from which nanoparticles are nucleated by gas phase condensation process. Optical emission spectroscopic studies reveal that a massive argon plasma ion density leads to the production of reactive atomic oxygen radicals that were responsible for the rapid oxidation kinetics. Non-stoichiometric tungsten-oxide in pale blue colour and nanometer sizes were deposited on the water-cooled walls of the vacuum chamber. This sample was annealed to produce nanocrystalline, tungsten-oxide in yellow colour, which was characterized with narrow size distribution and fine material crystallinity. Functional properties of the synthesized nanomaterials were also measured, their photocatalytic characteristics for the degradation of the dye Rhodamine-B and antibacterial properties against E. coli bacteria. The annealed powder sample could remove the dye almost completely in about three hours. The same nanopowders demonstrated promising antibacterial properties, which may therefore lead to multi-functionality during the treatment of wastewater. Their hydrogen evolution reaction activity is also investigated that demonstrates moderate performance.

Peptoids are biofunctional N-substituted glycine peptidomimics. Their self-assembly is of fundamental interest because they demonstrate alternatives to conventional peptide structures based on backbone chirality and beta-sheet hydrogen bonding. The search for self-assembling, water-soluble "minimal" sequences, be they peptide or peptidomimic, is a further challenge. Such sequences are highly desired for their compatibility with biomacromolecules and convenient synthesis for broader application. We report the self-assembly of a set of trimeric, water-soluble α-peptoids that exhibit a relatively low critical aggregation concentration (CAC ∼0.3 wt %). Cryo-EM and angle-resolved DLS show different sequence-dependent morphologies, namely uniform ca. 6 nm wide nanofibers, sheets, and clusters of globular assemblies. Absorbance and fluorescence spectroscopies indicate unique phenyl environments for ?-interactions in the highly ordered nanofibers. Assembly of our peptoids takes place when the sequences are fully ionized, representing a departure from superficially similar amyloid-type hydrogen-bonded peptide nanostructures and expanding the horizons of assembly for sequence-specific bio- and biomimetic macromolecules.

Nanoantibiotics are the new class of antibacterial agents that can be an alternative to the conventional antibiotics, which are expensive and require lengthy synthesis procedures. In view of such importance of nanoantibiotics, in the present study, we have systematically designed Al doped ZnO (AZO) via a co-precipitation method. ZnO nanoparticles own decent bactericidal activity against clinically isolated bacterial species, however, its bactericidal concentrations are compromised. To enhance the antibacterial efficiency of ZnO, different concentrations of Al was doped into ZnO lattice to design AZO nanorods, which were characterized using XRD, RAMAN, FESEM, DSC/TGA and Zetasizer. The XRD data confirmed a hexagonal wurtzite structure of AZO, while the bimetallic composition of the AZO was evaluated by RAMAN spectra and EDX. The average diameters of AZO nanorods were less than 100 nm. The zeta potential of ZnO was enhanced from 6.17 ± 0.5 to 22.7 ± 0.3 mV at 15% doping of Al. The biomedical value and commercial applicability of AZO nanorods were evaluated in terms of its biocompatibility using L929 mouse fibroblast and the antibacterial activity against Escherichia coli and Enterococcus hirae. The antibacterial activity was found to be significantly enhanced to ~ 19 times with MIC values of 14.33 ± 0.20 and 14.68 ± 0.20 µg/ml for AZO (15% doping) as compared to 254.88 ± 3.0 and 338.14 ± 9.0 µg/ml for ZnO against E. coli and E. hirae, respectively. The antibacterial mechanism was found to be electrostatic interaction between bacterial cell and AZO, followed by the intracellular accumulation of the Zn2+ ions. The release of Zn2+ ions from AZO was found to be kinetic controlled (diffusion limited). The synthesized nanorods showed excellent biocompatibility with more than 95 ± 3% of cell viability up to 6 days even at higher concentrations, indicating its promise for in vivo analysis. Hence, this study designates AZO as a plausible nanoantibiotic and unlocks its access for various other biomedical applications.

In the last few decades, biofuel cells have been explored extensively as an emerging technology and achieved the status of critical research endeavours among the intellectual communities working on power crisis across the world. The researchers around the globe are concentrating on harnessing the unique atomic and molecular properties of advance engineered materials, including nanotubes, nanosheets, nanoparticles and conducting polymers, on account of their capability to aid in the generation of efficient electricity from biological substrates using numerous biocatalysts. Because of the enhancement of nanotechnology, substantial milestones have been achieved in the realm of the biofuel cell, even though it is still challenging to uphold the performance of these cells. Implementation of nano materials and conducting polymers for biofuel cell assembly has been widely anticipated as an effective and capable approach to attain high power generation. In this review, we have documented the relevant and exciting methodologies used in the development of the enzyme based biofuel cells (EBC), focused on glucose as biofuel, using different nano materials utilized for EBC and emphasized the revolutions in this field. Every aspect of biofuel cell system including the fundamentals, charge transfer as well as the role of nano materials and conducting polymers in matrix development of electrode materials and its fabrication has been elucidated. To summarize the latest trend an extensive table has been incorporated including bio-sensing electrode, the enzymatic system mediator and output power density. Keywords: Biosensing electrodes, Glucose biofuel cells, Nano materials, Nanotubes, Graphene, Conducting polymers

Journal of alloys and compounds 749, 768 - 775 (2018). doi:10.1016/j.jallcom.2018.03.261, This paper demonstrates fine size-controlled synthesis of superparamagnetic carbon-encapsulated iron nanoparticles, by a supersonic plasma jet assisted rapid, bulk-production process, by manipulation of the pressure in the sample collection chamber. Transmission electron microscopy and small angle x-ray scattering measurements confirmed the formation of single-crystals with a narrow size distribution, having core average size of 5.0 nm and encapsulated by an ultrathin carbon coating, for sub-mbar pressure. VSM and Mossbauer characterization established the nanocrystallites to be superparamagnetic in nature, with saturation magnetization 67 emu/g and coercive field 7.4 Oe. Controlled plasma heating during synthesis led to the burning down of extra carbon that resulted in further enhancement of the magnetization of the product. Graphitization of the encapsulating layers also enhanced, which could successfully protect the metallic core from oxidation, as well as improved its cyto-compatibility. This purified sample could be ideal for targeted drugs delivery and water treatment applications. Another sample was processed through controlled reaction with oxygen, the as-synthesized sample having magnetic properties approaching that of the first sample, which may be more attractive especially for water treatment processes because of the simpler single-step processing of the material., Published by ScienceDirect, Amsterdam [u.a.]

World’s energy needs are majorly dependent on the fossil fuels, including petrochemical sources and coal. The alternate of these fuels include hydro and nuclear powers. However, all these resources are finite and current rate of consumption indicates the shortening of the fuels and energy in the near future. Diesel plays a remarkable role in the economy of the developing and developed countries in industry and other sectors being a basic fuel used in transportation. The increasing demand of alternate energy based on renewable resources and pollution-free production is a major concern these days for environmentalists. Biodiesel, in this regard is set to be the best entrant to acquire the desired alternative of conventional fuels. The production of biodiesel is carried out through transesterification reaction using edible oil feedstocks, which is not feasible for developing countries. Hence, utilization of low-grade feedstocks for biodiesel production is the new clinch for the developing countries. In general, the transesterification reaction is mediated by catalysts and hence, design of an effective catalyst is the key to produce efficient and commercially viable biodiesel. In this direction, it is necessary to understand the material chemistry of catalysts and mechanism of the catalytic transesterification reaction. This review enlightens the basics of transesterification, role of various process parameters and factors affecting biodiesel production from different feedstocks. In this review we have discussed various nanoporous heterogeneous catalysts investigated for biodiesel production and mainly focused on the mechanism involved in transesterification using heterogeneous catalysts. Keywords: Nanoporous materials, Biodiesel, Transesterification, Heterogeneous catalyst, Feedstocks, Yield

SARS-CoV-2 virus and other pathogenic microbes are transmitted to the environment through contacting surfaces, which need to be sterilized for the prevention of COVID-19 and related diseases. In this study, a prototype of a cost-effective sterilization box is developed to disinfect small items. The box utilizes ultra violet (UV) radiation with heat. For performance assessment, two studies were performed. First, IgG (glycoprotein, a model protein similar to that of spike glycoprotein of SARS-COV-2) was incubated under UV and heat sterilization. An incubation with UV at 70 °C for 15 min was found to be effective in unfolding and aggregation of the protein. At optimized condition, the hydrodynamic size of the protein increased to ~171 nm from ~5 nm of the native protein. Similarly, the OD280 values also increased from 0.17 to 0.78 indicating the exposure of more aromatic moieties and unfolding of the protein. The unfolding and aggregation of the protein were further confirmed by the intrinsic fluorescence measurement and FTIR studies, showing a 70% increase in the β-sheets and a 22% decrease in the α-helixes of the protein. The designed box was effective in damaging the protein's native structure indicating the effective inactivation of the SARS-COV-2. Furthermore, the incubation at 70 °C for 15 min inside the chamber resulted in 100% antibacterial efficacy for the clinically relevant E.coli bacteria as well as for bacteria collected from daily use items. It is the first detailed performance study on the efficacy of using UV irradiation and heat together for disinfection from virus and bacteria.

It has come to our attention that some of our cryo-electron microscopy (cryo-EM) images actually show ice contamination, (1) instead of the soft matter aggregates originally indicated in our publication. The images only relate to counterexample peptoid sequences that did not properly assemble (originally Figures 3D–K and S5E–G, I–M, and P). As such, our main finding of an ultrashort water-soluble tripeptoid assembling into ordered nanofibers is not changed. Our overall conclusions based on complementary cryo-EM, DLS, CAC, and fluorescence spectroscopy measurements are also unaffected. Nonetheless, the figures indicated and associated text require correction. In re-examining our cryo-EM data set, we found micrographs showing additional structures that are unlikely to be contaminants, which we previously took as less representative. Like the artifacts, the structures now identified are also irregular and consist of an ensemble of sizes centered around a mean. Incidentally, the mean sizes of these structures (50–250 nm in diameter, depending on sequence) fit better with our complementary DLS results—no agglomeration effect of individual 5–20 nm ice artifacts is needed anymore to reconcile the sizes measured by EM and DLS.

Here we report the effect of surface functionalization on Fe3O4 assembled nanoclusters with biopolymers, like chitosan and dextran using the solvo-thermal route. XRD analyses confirmed the formation of cubic spinel structure with crystallite sizes ranging from 11 to 14 nm. HRTEM analyses revealed the formation of spherical nanoclusters. Magnetic measurements demonstrate the typical ferromagnetic behavior with saturation magnetization (Ms) up to 71.048, 69.829 and 68.228 Am2Kg−1 for Fe3O4 (FO), chitosan coated Fe3O4 (CFO) and dextran coated Fe3O4 (DFO) respectively at room temperature. Negligible coercivity (Hc) and remenance (Mr) at room temperature implies nearly superparamagnetic behavior. Field cooled (FC) and Zero field cooled (ZFC) measurements of magnetization at an applied field of 100 Oe resulting in the blocking temperature above room temperature for all the samples. Induction heating ability of the samples under alternating magnetic field were studied by means of specific absorption rate measurements (SAR). It is shown that the surface functionalization significantly enhanced the SAR value up to 40% i.e., from 144.08 W/g for FO to 233.28 W/g for DFO at 1 mg/ml concentration. The study also concluded that the dipolar interactions are solely responsible for self-heating behavior of the nanoparticles. It was observed that by changing the sample concentration and different coatings, the final temperature can be tuned to the intended therapeutic (hyperthermia) temperature range (40–44 °C). The in vitro cytocompatibility test resulted in cell viability of more than 90%, which proved that the prepared nanomaterials are promising for the hyperthermia applications.

The present study reports laser surface texturing (LST) of Ti–6Al–4V using a Nd-YAG laser with a particular set of parameters and three different overlapping factors (OF): 0%, 25% and 50%. Biphasic calcium phosphate (BCP) film was deposited on bare as well as textured Ti–6Al–4V specimens by using radio frequency (RF) sputtering. The simultaneous effect of texturing as well as BCP coating on different physical and biological properties was investigated. The study revealed that the surface wettability of bare Ti–6Al–4V enhanced after laser texturing (as contact angle reduced from 89° to 71°-77°). It was further improved upon BCP deposition to make the Ti–6Al–4V superhydrophilic (contact angle ≈ 17°-21°). It was also observed that the surface roughness of bare Ti–6Al–4V significantly increased from Ra ≈ 94 nm to Ra ≈ 0.98–1.84 μm for different micro-dimpled texture substrates. The dimensions of micro-dimpled texture did not change after BCP deposition; however, a non-uniform film is deposited with increase in surface roughness. Protein adsorption was found as a function of surface hydrophobicity, which increased from 5.3 to 7.11 μg/cm2 with the rise in hydrophobicity of modified surfaces. Compared to bare Ti–6Al–4V and BCP deposited bare-Ti-6Al–4V surfaces, the BCP deposited textured surfaces exhibit higher number of well spread MG63 osteoblast cells. For the same surface chemistry, increase in surface area (roughness) improves cellular behavior. With texturing of the substrate, the cell adhered percentage and average cell area improved significantly and BCP-(50% OF)–Ti–6Al–4V was found to have the maximum cell spreading and proliferation. Overall, these findings revealed that a micro-dimpled textured surface followed by BCP film deposition strategy improved the physio-chemical properties of surfaces such as surface roughness and wettability. This in turn enhanced the bioactivity, cell adhesion and proliferation of bone cells (MG63) on modified Ti–6Al–4V surfaces and based on the results we envisage that can be potentially used for orthopedic and dental applications.

Remediation of heavy metal-contaminated soils has been drawing our attention toward it for quite some time now and a need for developing new methods toward reclamation has come up as the need of the hour. Conventional methods of heavy metal-contaminated soil remediation have been in use for decades and have shown great results, but they have their own setbacks. The chemical and physical techniques when used singularly generally generate by-products (toxic sludge or pollutants) and are not cost-effective, while the biological process is very slow and time-consuming. Hence to overcome them, an amalgamation of two or more techniques is being used. In view of the facts, new methods of biosorption, nanoremediation as well as microbial fuel cell techniques have been developed, which utilize the metabolic activities of microorganisms for bioremediation purpose. These are cost-effective and efficient methods of remediation, which are now becoming an integral part of all environmental and bioresource technology. In this contribution, we have highlighted various augmentations in physical, chemical, and biological methods for the remediation of heavy metal-contaminated soils, weighing up their pros and cons. Further, we have discussed the amalgamation of the above techniques such as physiochemical and physiobiological methods with recent literature for the removal of heavy metals from the contaminated soils. These combinations have showed synergetic effects with a many fold increase in removal efficiency of heavy metals along with economic feasibility.

In the recent years, considerable body of research has been carried out in the field of bioelectrochemical systems (BESs) for treatment of wastewater and generation of power. In these systems, different microbes are used for carrying out the transfer of electrons from medium to the anode electrode. The microbes employed are known as electrogens as they have the capacity to transfer electrons. Bacteria such as those belonging to the species such as Geobacter, Betaproteo, Deltaproteo and Desulfurnonas and of genus Shewanella are the commonly explored electrogens in BESs. In the past few years, a renewed interest in microbial fuel cell (MFC) research has developed, yet power generated from these devices has not significantly advanced. The primary reason for this non-advancement is that the research is more focused on improving power generation rather than on elementary understanding of the electron transfer processes. This review focuses on the methods used to study electron transfer processes in biofilms growing on the electrodes and presents several successful applications of MFCs. In this review, we have defined electrochemically active biofilms as biofilms that exchange electrons with conductive surfaces called electrodes.

International audience; We synthesized surfaces with different hydrophobicities and roughness by forming self-assembled monolayers (SAMs) of mixed amine and octyl silanes. Insulin aggregation kinetics in the presence of the above surfaces is characterized by a typical lag phase and growth rate. We show that the lag time but not the growth rate varies as a function of the amine fraction on the surface. The amount of adsorbed protein and the adsorption rate during the aggregation process also vary with the amine fraction on the surface and are maximal for equal parts of amine and octyl groups. For all surfaces, the growth phase starts for identical amounts of adsorbed insulin. The initial surface roughness determines the rate at which protein adsorption occurs and hence the time to accumulate enough protein to form aggregation nuclei. In addition, the surface chemistry and topography influence the morphology of aggregates adsorbed on the material surface and the secondary structures of final aggregates released in solution. (C) 2012 Elsevier B.V. All rights reserved.