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Chronic wounds are prone to fungal infections, possess a significant challenge, and result in substantial mortality. Diabetic wounds infected with Candida strains are extremely common. It can create biofilm at the wound site, which can lead to antibiotic resistance. As a result, developing innovative dressing materials that combat fungal infections while also providing wound healing is a viable strategy to treat infected wounds and address the issue of antibiotic resistance. Present work proposed anti-infective dressing material for the treatment of fungal strains Candida-infected diabetic foot ulcer (DFU). The nanofiber was fabricated using polyvinyl Alcohol/chitosan as hydrogel base and co-loaded with silver nanoparticles (AgNP) and luliconazole-nanoparticles (LZNP) nanoparticles, prepared using PLGA. Fabricated nanofibers had pH close to target area and exhibited hydrophilic surface suitable for adhesion to wound area. The nanofibers showed strong antifungal and antibiofilm properties against different strains of Candida; mainly C. albicans, C. auris, C. krusei, C. parapsilosis and C. tropicalis. Nanofibers exhibited excellent water retention potential and water vapour transmission rate. The nanofibers had sufficient payload capacity towards AgNP and LZNP, and provided controlled release of payload, which was also confirmed by in-vivo imaging. In-vitro studies confirmed the biocompatibility and enhanced proliferation of Human keratinocytes cells (HaCaT). In-vivo studies showed accelerated wound closure by providing ant-infective action, supporting cellular proliferation and improving blood flow, all collectively contributing in expedited wound healing. [ABSTRACT FROM AUTHOR]

Our aim was to develop multiwalled carbon nanotubes (MWCNTs)-based nanoconstructs for the codelivery of N -desmethyl tamoxifen (N-TAM) and a mild P-gp efflux inhibitor, i.e. , quercetin (QT) to treat multiple drug resistant (MDR) cancer cells. The hypothesis banks on three-tier attack on the MDR mechanisms viz. drug derivatization, MWCNT permeation and P-gp inhibition. Tamoxifen was converted to N-TAM and was conjugated to carboxylated MWCNTs mediated by a biodegradable linker, i.e. , tetraethylene glycol (TEG). QT was adsorbed on the conjugate to fetch the final product, i.e. , N- TAM-TEG-MWCNT-QT. Spectroscopic analysis confirmed successful conjugation of N-TAM and physical adsorption of QT. The in-vitro release of N-TAM from the N-TAM-TEG-MWCNT conjugate was minimal to that of pure drug under physiological conditions, but markedly enhanced under the acidic pH of cancer cells. The developed nanometeric formulation was found to be haemo-compatible. Reduced IC 50 values and better cellular uptake in drug resistant MDA-MB-231 cells were observed, followed by enhanced drug availability in the systemic circulation of rodents vis-à-vis naïve drug. The smart nanosystem conferred the desired temporal drug delivery, enhanced drug efficacy, biocompatibility and conducive pharmacokinetics, which are the crucial desired attributes to tackle the increasing concern of MDR in cancer chemotherapy. [ABSTRACT FROM AUTHOR]

Abstract: The fabrication of monolayer/multilayer films of Polyvinylpyrrolidone (PVP) stabilized NiCo alloy nanoparticles with an average particle size 7nm via Langmuir–Blodgett method is presented in this paper. The NiCo alloy nanoparticles were synthesized in ethanol using hydrazine hydrate as reducing agent at 60°C in the presence of PVP and washed with a mixture of chloroform–methanol (1:1) solution to get pure PVP capped alloy nanoparticles. The NiCo alloy suspension was spread to the interface of air/water and transferred to the glass surface. The formation of a Langmuir monolayer/multilayer of PVP stabilized NiCo particles at air/water interface were revealed with the pressure-area isotherm curve. The transfer of nanoparticles on the glass surface was found to be efficient for the first six layers as exhibited by the pressure-area isotherm and increases in absorption intensity in the UV–Vis range. The atomic force microscopy results show that this film has a cubic symmetry in a two dimensional (2D) array. [Copyright &y& Elsevier]

We report on enhanced nonlinear optical absorption and optical limiting in β-MnO 2 sponge-like nanowire network decorated with Ag nanoparticles excited by nanosecond laser. A simple two-step process is used to prepare the samples. The structure, morphology and the elemental analysis of the prepared samples are studied using x-ray diffraction, field emission scanning electron microscopy and energy-dispersive x-ray spectroscopy. Nonlinear optical absorption properties of the samples in solution is studied using the open aperture Z-scan technique employing 5 ns laser pulses at 532 nm. Nonlinear transmission measurements show that β-MnO 2 exhibit weak saturable absorption at low fluence and large optical limiting at high fluence, while upon decoration with Ag particles, Ag/β-MnO 2 shows strong saturable absorption at low fluence and enhanced optical limiting at higher fluence with an optical limiting threshold value three times lower than that of bare β-MnO 2 nanowires. The results indicate that these materials are potentially useful for constructing saturable absorbers and optical limiters. • β-MnO 2 nanowire network decorated with Ag nanoparticles. • Simple and cheap doped nanowire synthesis process. • Ag-doped β-MnO 2 nanowires may lead to cheap and efficient optical limiters. [ABSTRACT FROM AUTHOR]

• PFLD of Escherichia coli using M/biochar under visible light is reported. • Microscopic evaluations suggested detrimental effects on the bacterial membrane. • Resazurin assay suggested the hindrance of metabolic activity of PCD treated cells. • Treatment of M/biochar with HCT-116 cell lines showed ≈80 % cell viability. • PFLD treated water did not show any remarkable toxicity on growth of maize plants. Waterborne diseases caused by bacterial contamination of water sources remain one of the perilous public health challenges in low and middle-income countries. In this regards, we report a photo-Fenton like reaction for disinfection of water contaminated with common waterborne bacterium, Escherichia coli under visible light using biochar supported maghemite nanoparticles (M/biochar). Waste leaves of Cymbopogon flexuosus impregnated with ferric chloride were subjected to pyrolysis, which leads to the formation of M/biochar. M/biochar was found to be more effective than only Maghemite nanoparticles for disinfection of targeted bacterium in a photo-Fenton like process. Fluorescence and scanning electron microscopy images indicated compromization of bacterial cell membrane. Experimental evidence infers that hydroxyl radicals could be the major component responsible for disinfecting E. coli in the present process. Results obtained from Resazurin assay indicate that reactive oxygen species produced during photo-Fenton like reaction may have impeded the oxido-reductase protein system of the bacteria and hence hampered its metabolic activity. Proposed process has been successfully investigated for disinfection of real water samples contaminated with E. coli and treated water did not induce a noticeable toxic effect on the growth of maize plants and hence could have the potential for real world applications. [ABSTRACT FROM AUTHOR]

• Arsenic is removed with bilayered oleic acid functionalized iron oxide nanoparticles. • Maximum monolayer sorption capacity (q max) was 32.8 μg g−1 for As(V) in 120 min. • As(V) adsorption was heterogeneous and pseudo second order model fitted the data. • Antagonism of common anions follows the order: Cl– < SO 4 2– < NO 3 – < F– < PO 4 3–. • Adsorbent exhibited good As(V) removal performance from the cocktail mixture. Groundwater, one of the significant potable water resources of the geological epoch is certainly contaminated with class I human carcinogenic metalloid of pnictogen family which delimiting its usability for human consumption. Hence, this study concerns with the elimination of arsenate (As(V)) from groundwater using bilayer–oleic coated iron–oxide nanoparticles (bilayer–OA@FeO NPs). The functionalized (with high–affinity carboxyl groups) adsorbent was characterized using the state–of–the–art techniques in order to understand the structural arrangement. The major emphasis was to examine the effects of pH (5.0–13), contact times (0–120 min), initial concentrations (10–150 μg L–1), adsorbent dosages (0.1–3 g L–1), and co–existing anions in order to understand the optimal experimental conditions for the effective removal process. The adsorbent had better adsorption efficiency (∼ 32.8 μg g–1, after 2 h) for As(V) at neutral pH. Adsorption process mainly followed pseudo–second–order kinetics and Freundlich isotherm models (R2∼0.90) and was facilitated by coulombic, charge–dipole and surface complexation interactions. The regeneration (upto five cycles with 0.1 M NaOH) and competition studies (with binary and cocktail mixture of co–anions) supported the potential field application of the proposed adsorbent. [ABSTRACT FROM AUTHOR]

• ME coupling in'Y' doped double perovskite La 2 NiMnO 6 nanoparticles has been achieved. • Rhombohedral crystal structure with particle size in the range from ~16 to 22 nm has been achieved. • Evidence of strain mediated coupling. • 'α' (0.37793 mV/cm.Oe) is achieved for LNMO-4Y at 1902 Oe near room temperature. Nanoparticles of double perovskite La 2 NiMnO 6 (LNMO) and Yttrium (Y) doped La 2 NiMnO 6 (LNMO) were synthesized via sol-gel route. XRD pattern of LNMO and 'Y' doped LNMO confirm the formation of nanocrystals and crystallize in rhombohedral crystal structure. TEM images with SAED pattern also shows the nanocrystalline nature having the particle size ranging from ~16 to 22 nm. Particle size estimated from TEM is in well agreement with XRD results. FTIR spectra and Raman spectra confirm the presence of well-defined bands which are typical of double perovskite structures. The P-E hysteresis loop measurements confirm the enhanced ferroelectric nature of the magnetic double perovskite LNMO-4Y nanoparticles. The variation in maximum polarization with respect to applied magnetic field confirms the evidence of strong strain mediated coupling in the samples and estimated maximum value of magneto-electric coefficient 'α' (33 × 10−5 µC/cm2.Oe or 0.37793 mV/cm.Oe) is achieved for LNMO-4Y at 1902 Oe near room temperature. [ABSTRACT FROM AUTHOR]

• Waste frying oil methyl ester (WFME) as a substitute to conventional diesel fuel. • Effects of various parameters on various combustion parameters were analyzed. • Optimal combination of output parameters was predicted by CCD and RSM. • Every model has a statistically significant by using an analysis of variance. Growing environmental concerns and stringent emission regulations have fueled the search for an alternative fuel without engine modification that can minimize pollution from compression ignition (CI) engines. Biodiesel is a suitable alternative fuel to fossil diesel that is often made from edible or non-edible oils. The current investigation is primarily concerned with the usage of waste frying oil methyl ester (WFME) as a substitute for conventional diesel with titanium oxide (TiO 2) nanoparticles as additives in a CRDI diesel engine. In this work, the influence of WFME blend ratio (0–20%), injection pressure (IP) (400–600 bar) compression ratio (CR) (16–20), and concentration of TiO 2 nanoparticles (60–220 ppm) on various combustion parameters such as ignition delay (ID), maximum cylinder pressure (P max), combustion duration (CD), and heat release rate (HRR) were studied. The investigations were constructed with the use of a statistical technique known as Design of Experiments (DoE), which is based on the central composite design (CCD) of response surface methodology (RSM). The WFME biodiesel was found to be the best blend of input parameters at a 454 bar IP and 19.4 CR with diesel at 27.7% WFME biodiesel and 201 ppm TiO 2 NPs. Moreover, the desired output at aforesaid optimum combinations exhibited P max 67.1 bar, HRR 72.95(J/CAD), CD 42.54 (CAD), and ID 8.12 (CAD). Confirmatory tests confirmed the estimated combination, and the forecasting error was found to be within 4%. When it comes to improving the engine's performance, RSM's combination works best. [ABSTRACT FROM AUTHOR]

[Display omitted] • Spray combustion characteristics of boron-loaded slurry fuel are studied in a swirl-stabilized combustor. • XRD and TGA data of collected burnt products confirm that boron particles are completely oxidized. • The temperature data at the combustor exit suggest a positive thermal contribution from boron combustion and subsequent heat release. For many decades, liquid hydrocarbon fuels are being used to propel air-breathing engines. However, the energy content of liquid hydrocarbon fuels has reached close to its limitation. Any further improvement in energy value is quite difficult through chemical methods. Slurry fuels, which are colloidal suspensions of solid energetic particles in liquid fuel, became a potential alternative fuel. Among several solid additives, boron is considered the best choice because of its higher heating values. However, our knowledge about boron-loaded slurry fuel is very limited. Therefore, here in this study, we experimentally investigated the combustion characteristics of boron/Jet A-1 slurry fuel spray in a swirl-stabilized combustor. A particle loading of 10% by weight is considered here for the experiment. The feed boron, as well as the burnt boron samples, were characterized using standard material characterization techniques in order to understand the surface morphology, oxidation behavior, and active boron content. The combustion characteristics of slurry fuel were analyzed through spectroscopy and BO 2 * chemiluminescence imaging. Positive thermal contribution from boron combustion was quantified via temperature measurements at three different radial locations of the combustor exit. The spectroscopy and chemiluminescence signatures indicate that combustion of boron particles occurs downstream of the dump plane. The exit temperature of boron-laden slurry fuel measured at all three different radial locations is higher compared to neat Jet A-1. An increment of 19% in exit temperature was observed in the case of boron slurry fuel relative to neat Jet A-1. The X-ray diffractograms (XRD) and thermogravimetric analysis (TGA) show the complete oxidation of boron particles. [ABSTRACT FROM AUTHOR]

Abstract: The presence of surfactants (Hexamine, tetraethylammonium bromide (TEAB), cetyltrimethylammonium bromide (CTAB), tetraoctylammonium bromide (TOAB) and PVP) on the surface of zinc oxide (ZnO) nanoparticles resulted variation in their optical properties. The optical properties of each surfactant-capped zinc oxide nanoparticles were investigated using UV–visible absorption and fluorescence techniques. The particle size of these nanoparticles were calculated from their absorption edge, and found to be in the quantum confinement range. The absorption spectra and fluorescent emission spectra showed a significant blue shift compared to that of the bulk zinc oxide. Large reduction in the intensity of visible emission of zinc oxide/surfactant was observed and these emissions were vanished more quickly, with the decrease in excitation energy, for the smaller nanoparticles. Out of the four surfactants (other than PVP), CTAB-capped zinc oxide has smallest particle size of 2.4nm, as calculated from the absorption spectrum. Thus the presence of surfactant on the surface of zinc oxide plays a significant role in reducing defect emissions. Furthermore, ZnO/PVP nanoparticles showed no separate UV emission peak; however, the excitonic UV emission and the visible emission at 420nm overlap to form a single broad band around 420nm. [Copyright &y& Elsevier]

The structural, microstructural, and optical properties of Mg-doped ZnO nanoparticles prepared via. thermal decomposition route. The Rietveld analysis was executed for prepared sample, which revealed that the hexagonal wurtzite structure for all samples along with changes in lattice parameters and bond length. The various relevant parameters, such as strain, stress, and energy density, are analyzed using different improved forms of W-H equations via. a complete Willamson-Hall (W-H) method. Scanning electron microscopy (SEM) analysis resultant that the synthesized nanoparticles (NP's) are nearly spherical for Zn 1-x Mg x O, up to x = 0.04, and transform into a rectangular shape for x = 0.10. UV–Visible spectroscopy revealed an observation of fundamental absorption peak around 375 nm, which further shifted towards the higher wavelength, recommended the blue shift in the bandgap energy. The photoluminescence (PL) studies show a green emission band at 550 nm, demonstrating the occurrence of oxygen vacancy defects in the lattice of ZnO. Zn 1-x Mg x O (0≤ × ≤0.10) nanoparticles have been prepared by the thermal decomposition method. Structural, microstructural, and optical properties of ZnO nanoparticles were examined under the 'Mg' doping. X-ray diffraction pattern obtained for Zn 1-x Mg x O (0≤ × ≤0.10) confirms its hexagonal wurtzite structure. The Rietveld analysis performed for a prepared sample revealed that the lattice parameters and bond length are enhanced by increasing Mg%. The various relevant parameters, such as strain, stress, and energy density, are analyzed using different improved forms of W-H equations by a complete Willamson-Hall (W-H) method. Scanning electron microscopy (SEM) analysis derived that the synthesized nanoparticles(NP's) are nearly spherical for Zn 1-x Mg x O, up to x = 0.04, and transform into a rectangular shape for x = 0.10. UV–Visible spectroscopy revealed an observation of fundamental absorption peak around 375 nm, which further shifted towards the higher wavelength, recommended the blue shift in the bandgap energy. FTIR analysis Validate the existence of Zn-O stretching mode due to the presence of absorption modes in 400–600 cm−1 for all the samples. The photoluminescence (PL) studies show a green emission band at 550 nm, demonstrating the occurrence of oxygen vacancy defects in the lattice of ZnO. Image 1 • XRD and Rietveld refinement confirms the hexagonal wurtzite structure for all samples. • A small variations in lattice parameters provoked by Mg doping. • Through Willamson-Hall approach strain, stress and energy density were calculated. • Tailoring in bandgap energy has been found with Mg doping which is useful for optical devices. • Evidence of oxygen vacancy defects observed through PL studies. [ABSTRACT FROM AUTHOR]

The rapid development of nanomedicine has increased the likelihood that manufactured nanoparticles will one day come into contact with people and the environment. A variety of academic fields, including engineering and the health sciences, have taken a keen interest in the development of nanotechnology. Any significant development in nanomaterial-based applications would depend on the production of functionalized nanoparticles, which are believed to have the potential to be used in fields like pharmaceutical and biomedical sciences. The functionalization of nanoparticles with particular recognition chemical moieties does result in multifunctional nanoparticles with greater efficacy while at the same time minimising adverse effects, according to early clinical studies. This is because of traits like aggressive cellular uptake and focused localization in tumours. To advance this field of inquiry, chemical procedures must be developed that reliably attach chemical moieties to nanoparticles. The structure-function relationship of these functionalized nanoparticles has been extensively studied as a result of the discovery of several chemical processes for the synthesis of functionalized nanoparticles specifically for drug delivery, cancer therapy, diagnostics, tissue engineering, and molecular biology. Because of the growing understanding of how to functionalize nanoparticles and the continued work of innovative scientists to expand this technology, it is anticipated that functionalized nanoparticles will play an important role in the aforementioned domains. As a result, the goal of this study is to familiarise readers with nanoparticles, to explain functionalization techniques that have already been developed, and to examine potential applications for nanoparticles in the biomedical sciences. This review's information is essential for the safe and broad use of functionalized nanoparticles, particularly in the biomedical sector. • Surface functionalization of Nanoparticles. • Types and properties of nanoparticles. • Synthesis of nanoparticles. • Application of nanoparticles. [ABSTRACT FROM AUTHOR]

Through digestive ripening (DR), a polydispersed colloid can be processed to obtain a monodispersed system. Recent advances in DR have rendered the process prospectively scalable, soft-chemical and green. This in turn makes it relevant for industrial-scale manufacturing of nanoparticles (NPs) and quantum dots (QDs); a crucial step forward from a technological standpoint. However predictive models and associated results that offer chemical insights for experimental design for DR are largely missing. Currently two attempts to explain DR are notable: (i) Lee’s theory (essentially accounts for surface electrostatic enthalpy), and (ii) Clark’s model (flow-flux modelling across interfaces around the NP). Given recent experimental results, hard-soft-acid-base interactions associated with surfactant-surface interface seem essential. In this work, an expression is written to account for hard-soft-acid-base-interactions on particle surface, and dynamics of particle size evolution is simulated using an agent based approach. Parametric studies indicate following trends for the convergent radius: (a) considerable variance with surface charge, (b) considerable variance with surface energy, (c) dependence on absolute temperature which is almost entirely due to the thermal dependence of the solubility product term, and (d) a linear relationship to the negative logarithm of product of solubility and bulk diffusion constant. The solubility term, in light of recent reports, needs to be interpreted also in terms of solute solubility in the interfacial surfactant phase. The solvation-precipitation approach provided here offer preliminary but experimentally-relevant and computationally-grounded physico-chemical insights for design of DR experiments. [ABSTRACT FROM AUTHOR]

The present article deals with synthesis of sol–gel derived tin dioxide (SnO 2 ) nanoparticles encapsulated in to guar gum (GG) biopolymer as the organic–inorganic hybrid materials for the determination of hydrazine. The organic–inorganic hybrid combines the perfunctory strength offered by the inorganic SnO 2 nanoparticles with flexible binding sites provided by the organic biopolymer (GG) solution by the ultrasonication. The phase identification, crystalline size, surface morphology and optical properties of prepared SnO 2 and SnO 2 -GG nanocomposites has been investigated through FT-IR, XRD, SEM, AFM, TEM, UV–Vis, and PL techniques. The colloidal solution of SnO 2 and GG is electrophoretically deposited (EPD) onto the indium tin-oxide (ITO) glass substrate and studied for the electrooxidation of hydrazine. Under the optimized experimental conditions, the linearity between the current response and the hydrazine concentration has been obtained in the range of 2–22 mM, with a low detection limit of 2.76 mM and a high sensitivity of 5.72 μA cm − 2 . Based on the linear increase in amperometric current, a sensitive hydrazine electrochemical sensor is constructed. The proposed SnO 2 -GG/ITO electrode shows a good response time (35 s), reproducibility, and long-term stability. The obtained results suggest that SnO 2 -GG nanocomposites electrode provides a favorable sensing platform for the electrochemical studies. In addition, the cyclic voltammetry (CV) studies are used to evaluate the kinetic parameters. [ABSTRACT FROM AUTHOR]

Abstract: The rivastigmine (RHT) loaded chitosan nanoparticles (CS-RHT NPs) were prepared by ionic gelation method to improve the bioavailability and enhance the uptake of RHT to the brain via intranasal (i.n.) delivery. CS-RHT NPs were characterized for particles size, particle size distribution (PDI), encapsulation efficiency, zeta potential and in vitro release study. Nose-to-brain delivery of placebo nanoparticles (CS-NPs) was investigated by confocal laser scanning microscopy technique using rhodamine-123 as a marker. The brain/blood ratio of RHT for different formulations were 0.235, 0.790 and 1.712 of RHT (i.v.), RHT (i.n.), and CS-RHT NPs (i.n.) respectively at 30min are indicative of direct nose to brain transport bypassing the BBB. The brain concentration achieved from i.n. administration of CS-NPs (966±20.66ngml−1; t max 60min) was significantly higher than those achieved after i.v. administration of RHT sol (387±29.51ngml−1; t max 30min), and i.n. administration of RHT solution (508.66±22.50ngml−1; t max 60min). The higher drug transport efficiency (355±13.52%) and direct transport percentage (71.80±6.71%) were found with CS-RHT NPs as compared to other formulation. These results suggest that CS-RHT NPs have better brain targeting efficiency and are a promising approach for i.n. delivery of RHT for the treatment and prevention of Alzheimer’s disease (AD). [Copyright &y& Elsevier]

Abstract: The purpose of the present investigation was to prepare venlafaxine (VLF) loaded chitosan nanoparticles (NPs) to enhance the uptake of VLF to brain via intranasal (i.n.) delivery. VLF loaded chitosan NPs were prepared and characterized for particle size, size distribution, zeta potential, encapsulation efficiency and in vitro drug release. In order to investigate the localization of chitosan NPs in brain and other organs qualitatively confocal laser scanning microscopy technique was carried out using rhodamine-123 (ROD-123) as marker. The levels of VLF in plasma and brain tissues were also determined, the brain/blood ratios of VLF for VLF (i.v.), VLF (i.n.), VLF chitosan NPs (i.n.) were 0.0293, 0.0700 and 0.1612, respectively, at 0.5h, indicative of better brain uptake of VLF chitosan NPs. The higher drug transport efficiency (508.59) and direct transport percentage (80.34) of VLF chitosan NPs as compared to other formulations suggest its better efficacy in treatment of depression. [Copyright &y& Elsevier]