Concentration Of Nanoparticles Research Articles

Charge-patterned nanofiltration membranes with polystyrene sulfonate particles and polyethyleneimine in cross-linked polyvinyl alcohol

Removing salinity has always been a challenge for wastewater treatment. Utilizing nanofiltration (NF) membranes is a promising approach. However, currently available NF membranes are less effective in monovalent salt removal. In this study, work toward the initial aim of fabricating charge mosaic membranes led to charge-patterned NF-selective films on polyether sulfone (PES) or polyacrylonitrile (PAN) support membranes, with similar rejection for mono- and divalent salts. The membranes were fabricated by a two-step layer assembly of first negatively charged polystyrene sulfonate (PSS) particles immobilized in a polyvinyl alcohol (PVA) layer, followed by coating a positively charged polyethyleneimine (PEI) layer. Both PVA and PEI were crosslinked using glutaraldehyde that had initially been impregnated into the support membrane. The type of support membrane, nanoparticle, PVA, and PEI concentrations during fabrication, as well as feed pH and salt concentration, play significant roles in separation performance of obtained composite membranes. Charge-patterned NF membranes fabricated using 0.5 wt.% PVA and 0.05 wt.% PSS for assembly of the first layer followed by coating 0.5 wt.% PEI solution had even somewhat higher rejection for monovalent salt (NaCl; ∼82%) compared to multivalent salts (Na2SO4, MgSO4, and MgCl2; ∼74%), at a permeance of 5.5 LMH/bar on the PES and 3.1 LMH/bar on the PAN support membrane.

Inhibition and Scavenging Free Radicals Activities by Natural Antioxidant: Honey Nanoparticles

Honey nanoparticles have shown numerous unique characteristics such as biocompatibility and are excellent agents for biological applications. This study aims to investigate honey nanoparticles for 2, 2-diphenyl-1-picryl-hydrazyl-hydrate (DPPH) free radical scavenging activity and their ability to offer protection against gamma radiation. In vitro antioxidant activity study of honey nanoparticles has shown good free radical scavenging activity for DPPH radical assayed within a concentration range of (0.05–2.5)[Formula: see text]×[Formula: see text][Formula: see text][Formula: see text]g/l, at higher concentrations of nanoparticles showed reverse trend in absorbance and inhibition indicating this finite range of concentration is suitable for scavenging free radicals, also nanoparticles were found to have significant antioxidant capacity and thus can be used as potential radical scavenger against deleterious damages caused by the free radicals.

Characterization and anticancer evaluation of zirconia nanoparticles synthesized via green route using sophora flavescens roots extract

The emergence of drug resistance in cancer cells has impeded recent progress in cancer therapy, leading to the investigation of novel anticancer drugs. The fabrication of metal and ZrO2 nanoparticles is a promising path with prospective applications across diverse technological domains. The present study investigates the potential anticancer effects of ZrO2 NPs obtained from the root extract of Sophora flavescens on MCF-7 breast cancer cells. The structural and chemical features of these nanoparticles are analyzed using several techniques such as flow cytometry, SEM, TEM, FTIR, and UV–vis spectroscopy. The examination of XRD and TEM images demonstrates the significant contribution of plant root extract in enhancing the efficiency of nanoparticles, leading to the formation of nearly tetragonal crystal structures with an average size of 8 nm. The MTT experiment verifies the nanoparticles' anticancer activity, which depends on the dosage. The IC50 value of 253 μg/mL indicates the half-maximal inhibitory concentration. The optical microscope reveals an unusual sight: MCF-7 cells appear more spherical and less dense at higher concentrations. This research also investigates the antibacterial properties of ZrO2 nanoparticles against harmful bacteria, particularly those resistant to multiple drugs. The diffusion disk assay indicates that the nanoparticles are active against drug-resistant isolates, with zones of inhibition ranging from 31 to 55 millimeters. Additionally, the researchers noted a positive correlation between nanoparticle concentration and the size of the inhibition zone. Overall, the data indicates the potential of ZrO2 NPs to aid in cancer therapy as well as in combating infections.

Both radially varying viscosity and thermal micropolar effect on MHD Newtonian nanofluid flow through a porous media

The purpose of this research is to discuss the impact of radially varying viscosity on MHD peristaltic transport in a micropolar Newtonian nanofluid. The fluid moves through a porous media under the influence of ohmic dissipation and radiation. The mathematical equations governing the system were modified with long-wavelength and low-Reynolds number approximations. They were then solved using the homotopy perturbation method. A set of graphs illustrate numerical results regarding the relationships between axial velocity, micro-rotation velocity, temperature and nanoparticle concentration with physical variables. It is observed that both the micro-rotation velocity and temperature magnify with an increase in the value of Eckert number. Meanwhile, the value of the axial velocity reduces with an increase in the value of Eckert number. Furthermore, the current study has many applications in several scientific areas such as the medical industry, medicine and others. Gold nanoparticles can also be used to treat cancerous tumours.

Biodegradable glycine betaine encapsulated chitosan nanoparticles induce the expression of antioxidant enzyme genes to improve drought tolerance in maize

Drought is one of the main abiotic stresses that affect the growth and development of maize crop, thus causing food crises across the world. Nanoparticles are considered an effective tool for improving crop yield by upgrading the plant tolerance mechanism under abiotic stress. In this study, we investigated the role of foliar application of glycine betaine-encapsulated chitosan loaded nanoparticles (LNPs) and unloaded chitosan nanoparticles (NPs) in improving morphological, physiological, biochemical and molecular attributes in two maize varieties, HNG and CZP, grown under drought stress. Petri plates experiment was performed to screen different levels of drought (5 % and 20 %) and nanoparticle concentrations (10, 20 and 40 μg NPs). In the pot experiment, 20 % drought stress along with 20 μg LNPs and 20 μg NPs were used to examine the morphological, physiological and biochemical attributes of maize plants. Drought stress led to a significant reduction in fresh and dry weight, relative water content, root and shoot lengths, photosynthetic pigments, and antioxidant enzyme activities, including catalase, superoxide dismutase, ascorbate peroxidase, and proline content compared to control plants. However, foliar application of LNPs resulted in increased photosynthetic pigments, enhanced antioxidant enzyme activity, and elevated proline content under both control and drought-stressed conditions. Conversely, malondialdehyde (MDA) content decreased significantly with the application of LNPs and NPs alone under stress conditions. Moreover, nanoparticles also enhanced the relative expression levels of antioxidant genes, ZmAPX, ZmCAT, and ZmSOD. These findings highlight the potential of LNPs as an ecofriendly which helps in ameliorating drought stress in maize, and other plants.

Experimental and statistical investigation on the dielectric breakdown of magneto nanofluids for power applications

The insulating oil serves the dual purpose of providing insulation and cooling within transformers. This investigation aims to explore the impact of various nanoparticles on the dielectric breakdown voltage (BDV) of dielectric oils. The study examines the effect of the concentration of magnetic nanoparticles on the dielectric breakdown voltage of insulating oils. Nanoparticles such as iron (II, III) oxide (Fe3O4), cobalt (II, III) oxide (CO3O4), and ferrous phosphide (Fe3P) were utilized to create nanofluids with carrier mediums consisting of mineral oil and synthetic ester oil. BDV determination was conducted using a VDE and S–S electrode system according to IEC 60156 standards. Nanofluid were prepared using a two-step method, and their concentrations ranged from 0.01 g/L, 0.02 g/L, and 0.04 g/L in base oils. Twelve iterations were conducted for each prepared nanofluid, and breakdown voltage measurements were recorded. The results indicate a noteworthy enhancement in the breakdown voltage of nanofluids. The statistical analysis was performed on the dielectric property of nanofluid samples for better breakdown accuracy. The maximum enhancement at specific nanoparticle concentrations was shown by each nanofluid. The results show that under the S–S electrode configuration, the greatest overall enhancement was observed for Fe3P in mineral oil, with an enhancement of 70.05%, and Fe3O4 in synthetic ester oil, with an enhancement of 46.29%.

Highly luminescent, fast switching electro-optical device based on core-shell bimetallic nanoparticles/ ferroelectric liquid crystal composites.

Owing to the passive nature of liquid crystal (LC) materials, achieving luminous displays using pure LC materials is challenging. In addition, it is difficult to achieve a fast switching time using pristine ferroelectric LC devices without compromising their cell thickness. Herein, we have developed a fast switching and highly luminescent electro-optical device by dispersing a minute concentration of bimetallic nanoparticles (Au@Ag NPs) having a spherical gold core and a silver shell within a ferroelectric liquid crystal (FLC) host matrix, ZLI3654. Au@Ag core-shell NPs having synergic attributes of both counterparts were successfully synthesized by a facile seed-mediated route. The Au core helps to tune the shape of the Ag shell and provides enhanced electron density as well as improved stability against oxidation. Introducing nanoparticles induces little structural modifications to the host FLC, resulting in an improvement in the mesogenic alignment. Interestingly, ∼29-fold enhancement in the photoluminescence (PL) intensity is observed on dispersing 0.25 wt% of Au@Ag NPs into the FLC host matrix. The enhanced electromagnetic field in the FLC-nanocomposite is attributed to the Localized Surface Plasmon Resonance of Au@Ag NPs, which strengthens the photon absorption rates by the FLC molecules, culminating in the massive enrichment of the PL intensity. In addition, the improved localized electric field inside the FLC device led to a noticeable enhancement in the spontaneous polarization, dielectric permittivity, and, most interestingly, ∼53% fastening in the switching time at an optimum concentration (0.25 wt%) of Au@Ag NPs. The improved electro-optical parameters of the Au@Ag NPs/FLC composite have been compared with the performance of both pristine Au NPs/FLC and Ag NPs/FLC composites, respectively, for the comprehensiveness of the study. The present study paves a systematic way to develop FLC-based advanced electro-optical devices with faster switching and higher luminescence properties.

Influence of Deposition Temperature and WC Concentration on the Microstructure of Electroless Ni-P-WC Nanocomposite Coatings with Improved Hardness and Corrosion Resistance

This study aims to develop Ni-P coatings with high P content (≥11 wt.%) reinforced with WC nanoparticles on F22 steel substrates. The introduction of conductive WC in the plating solution dramatically increases reactivity of the plating solution, and consequently a tuning of deposition parameters, in terms of temperature and WC concentration, is required to obtain nanocomposite coatings with improved mechanical properties. The coatings’ porosity and incorporation and dispersion of the reinforcing phase as a function of temperature and WC concentration were analyzed by quantitative image analysis from Scanning Electron Microscopy (SEM) micrographs. Increasing the temperature and concentration of nanoparticles leads to a faster plating rate and a dramatic increase in both porosity and agglomeration of the reinforcing phase, with detrimental effects on the coatings’ microhardness. The best compromise between coating parameters was obtained by deposition at 70 °C and 6.5 g/L of WC, with a plating rate ≈ 12 μm/h, porosity lower than 1.5%, and a good combination between particle incorporation and agglomeration. In these conditions, a hardness increase by 34% is achieved in comparison to standard Ni-P. Coatings were then heat treated in air at 200 °C for 2 h, to induce growing stress relaxation, or 400 °C for 1 h, to study effects of crystallization and precipitation. X-Ray Diffraction (XRD) analysis demonstrated that WC introduction does not alter the microstructure of Ni-P coatings, but delays grain growth coarsening of precipitates. Hardness improvement by 6.5% and 45% is registered after treatment at 200 °C and 400 °C, respectively. An increase in elastic modulus, measured by instrumented indentation, was found in WC-reinforced coatings compared with Ni-P. Potentiodynamic polarization tests revealed that both introduction of WC nanoparticles and heat treatment also enhance corrosion resistance.

Microscopic mechanism of nanofluids electrospray: A molecular dynamics study

Cone-jet electrospray is widely used in various fields, such as electrospinning, nanostructured porous coating preparation, and inkjet printing, for which it can produce a large number of monodisperse and high charge-to-mass ratio droplets. A molecular dynamics method is employed to investigate the cone-jet electrospray emission behavior of nanofluids, where the microscopic mechanism of cone-jet electrospray including the formation of the cone, disintegration of the jet, stability of hydrogen bond, and interactions between molecules is revealed. In this paper, the influence of operating parameters and liquid physical properties were numerically conducted and extensively analyzed. The results show that the cone-jet electrospray only occurs in a certain range of applied voltage and flow rate, and the temperature and concentration of nanoparticles have a great effect on the jet length and the number of clusters produced by jet disintegration. When the electric field intensity increases, the length of the jet and the number of clusters increase. However, regardless of the electric field intensity, the maximum axial density is always located near the capillary outlet and the maximum radial density is located at the central axis of the capillary. As the temperature increases, the number of clusters increases significantly due to the synthetical effect of electric field-induced disintegration and evaporation, whereas the jet length is reduced. With an increase in concentration of nanoparticles at room temperature, the Taylor cone not only appears earlier but also has a larger angle. Meanwhile, the non-bonded interactions between ethanol molecules become stronger. This work provides microscopic mechanisms of nanofluids cone-jet electrospray and is potentially useful to optimize the design parameters of industrial applications.

Unsteady flow of nanofluid over a sheet of variable thickness with nonlinear kinematics

The transport of heat in an unsteady flow of nanofluid has been discussed in this paper. The flow is maintained over a non-flat, variably porous, and moving sheet in the present simulation. Moreover, the sheet has both constant temperature and nanoparticle concentration at its surface. Unsteadiness in all field variables (i.e. the flow, temperature, and nanoparticles concentration) has been produced by the time-dependent quantities, specified at the surface of the sheet (i.e. kinematics of sheet). The well-known Buongiorno model of nanofluid has been undertaken in the present studies. Furthermore, the simulation includes the particular cases of uniform and linear (polynomial & algebraic functions) stretching/shrinking and injection/suction velocities. Besides that observations of the same nature have been recorded for the non-flat sheet. The boundary layer form of the governing PDEs has been utilized to evaluate the exact status of field variables in the flow domain. Appropriate conditions are imposed by considering the geometry of the flow problem. The problem at hand is simplified by introducing a new set of functions for the field variables because of boundary inputs. After this treatment, the system of boundary value ODEs, which contains several dimensionless numbers (parameters), has appeared, and the problem is solved numerically for various values of parameters, involved in it. More precisely, effects of unsteadiness, wall roughness, surface deformation parameters, Prandtl, Schmidt, thermophoretic, and Brownian motion numbers have been seen on profiles of four field variables. Besides that, the numerical results are also obtained for the skin friction coefficient, Nusselt, and Sherwood numbers. The present modelled problem and its solution are compared with classical models of that particular nature and with their solutions.

Foraminiferal detoxification breakdown induced by fatal levels of TiO2 nanoparticles

The increase discharge of titanium dioxide (TiO2) nanoparticles, derived from engineered material waste, exerts a detrimental impact on both the marine ecosystem and public health. The cytotoxicity of TiO2 nanoparticles on marine organisms should be imperatively understood to tackle the urgent concern for the well-being of marine life. Various concentrations of TiO2 nanoparticles have proven to reach fatal levels in aquatic organisms, requiring a deeper exploration of cytotoxicity. Notably, certain benthic foraminifers, such as Ammonia veneta, have been identified as capable of incorporating TiO2 nanoparticles into vesicles. However, these organisms exhibit a detoxification mechanism through exocytosis, as indicated by previous transcriptomic inferences. This presents the advantage of assessing the tolerance of foraminifers to TiO2 nanoparticles as pollutants and investigating the long-term effects of cytotoxicity. In this study, we scrutinized the distribution of TiO2 nanoparticles within cells and the growth rates of individuals in seawater media containing 1, 5, 10, and 50 ppm TiO2 nanoparticles, comparing the results with a control group over a 5-week period, utilizing A. veneta stain. Transmission electron microscopy observations consistently revealed high concentrations of TiO2 nanoparticles in vesicles, and their expulsion from cells was evident even with exposure to 5 ppm TiO2 nanoparticles. Under the control and 1 ppm TiO2 conditions, foraminifers increased their cell volume by adding a calcification chamber to their tests every 1 or 2 days. However, the 5-week culturing experiments demonstrated that foraminifers gradually ceased growing under 5 ppm TiO2 nanoparticle exposure and exhibited no growth at > 10 ppm concentrations, despite an ample food supply. Consequently, these findings with A. veneta suggest that the foraminiferal detoxification system could be disrupted by concentrations exceeding 5 ppm of TiO2 nanoparticles. The toxic effect of TiO2 nanoparticles on meiofauna, such as benthic foraminifers, have been poorly understood, though these organisms play an important role in the marine ecosystem. Environmental accumulation of TiO2 nanoparticles on the coast has already exceeded twenty times more than foraminiferal detoxification level. Future studies focusing on toxic mechanism of TiO2 nanoparticles are crucial to prevent the breakdown of the marine ecosystem through accelerating discharge of TiO2 nanoparticles into the ocean.

Development and characterisation of agar/silver nanoparticles-based film from Gracilaria canaliculata for food packaging

Gracilaria canaliculata was used as a novel source to extract agar, and for the green synthesis of silver nanoparticles. Silver nanoparticles (0.1 - 0.3%) were incorporated into the agar matrix to develop an environment-friendly food packaging material using the solution casting method. The concentration of nanoparticles affected the physical, thermal, and mechanical properties of the films. Films containing higher concentrations of silver nanoparticles exhibited promising properties, and demonstrated strong antimicrobial activity against both Gram-negative and Gram-positive foodborne pathogens. The film formulation exhibited no cytotoxic effect on HepG2 cells, with cell viability exceeding 94%. These findings suggested that the film possessed favourable characteristics for use as a food packaging material, presenting a potential alternative to plastics.

Effects of magnetic fields and nanoparticle concentration on hydro-thermal performance of a surface enhanced microchannel

This article numerically investigates fluid flow and heat transfer in plain wall (PWMC) and oblique fin (OFMC) microchannels under varying magnetic fields using water- Al2O3 nanofluid as a working fluid. Effects of magnetic flux (Hartmann number, Ha = 0–30), fluid velocity (Reynolds number, Re = 100–500), and nanoparticle volume fraction (ϕ = 0%–2%) on the overall thermo-fluid performance are analyzed. Magnetic fields can significantly improve the heat transfer in OFMC in a higher rate compared to the PWMC. Also, there is a less increment on the pressure drop in the OFMC in comparison to PWMC. In addition, individual, as well as combined effect of Joule and viscous heating on the thermo-fluid performance is investigated. Due to the combined effect of Joule and viscous heating, the Performance Evaluation Criterion (PEC) in OFMC can be improved by 21%. However, the PEC in OFMC can be enhanced by 55% without considering the combined effect. The detailed characteristics flow and heat transfer are also studied by analyzing the velocity contours, isotherms, streamlines, friction factors, and Nusselt numbers. The present study concludes the importance of consideration of Joule and viscous heating for an accurate modeling, where the viscous heating plays the dominant role. The present findings can be instrumental in enhancing the performance of micro heat sinks to optimize hydrothermal performance in high powered motors, nuclear fusion reactors etc., where magnetic field is present.

A novel approach to detect glucose concentration using active cavity Whispering Gallery Mode sensor

AbstractThis paper presents a new approach to particle detection using an active microresonator operating in the transparency regime. Simulations demonstrate that when particles interact with the microresonator surface, they induce optical losses. To compensate for these losses, the optical gain is amplified to restore the transparency regime. Simulation results show a linear relationship between nanoparticle concentration and the pump power required to compensate for optical losses. By the use of microresonator with a very high quality factor, this approach offers an accurate and sensitive method for detecting nanoparticles, without the need for complex equipment.

Numerical study on nanofluidic transport mechanism in Ellis flow within curved channel comprising compliant walls subjected to peristaltic activity

Peristaltic movement of fluid flows has significant applications in biomedical engineering, medicine, human physiology, etc. Specifically, it is very useful to understand and cure the very common intestinal diseases in human beings. A number of theoretical and empirical models are used to analyze peristaltic movement. In this work, the peristaltic movement of nanofluid is modeled with a non-Newtonian Ellis fluid model in a curved channel with compliant wall properties. The effects of Brownian motion, thermophoresis, and nonlinear radiations are considered in the heat transfer for better thermal analysis. The mathematical modeling of the physical problem yields the nonlinear partial differential equations with boundary conditions. First, the governing partial differential equations are non-dimensionalized, and then the resultant system is simplified by using the assumptions of a small Reynolds number and long wavelength. Then the obtained boundary value problem of differential equations is solved with the built-in Mathematica command NDSolve. The accuracy and reliability of the adopted procedure are verified by comparing the computed results with the reported literature. The impacts of the pertinent parameters (Brownian motion, thermal radiation, mixed convection, and thermophoresis phenomenon) on thermal energy, velocity, concentration, heat transfer rate, and stress at the lower wall are analyzed both in qualitative and quantitative manners. This study revealed some interesting facts, such as the peristaltic-driven motion of nanoliquid is strongly influenced by wall properties (i.e., wall elasticity, mass density, and wall damping). In addition, the flow experienced more resistance in the case of larger wall damping, but larger wall elasticity and mass density provide favorable movement for fluid motion. In addition, mixed convection plays a vital role in heat transfer and nanoparticle concentration in the curved domain. In addition, the curved channel walls have a higher stress factor than straight-plane channels. The results of the current study are very useful to understand many biological phenomena, such as the peristaltic movement of liquid during dialysis, food movement through the intestine, etc.

An effective parametric sensitivity analysis to improve electrical and thermal energy/exergy efficiency of PVT system using nanofluid

A 3D steady-state model of a photovoltaic/Thermal system with nanofluid is studied to investigate the electrical and thermal performance of PVT by utilizing a combination of statistical modeling and numerical simulation. The 3D CAD (Computer Aided Design) modeling of the photovoltaic thermal (PV/T) is performed using Ansys Space Claim. The current study is based on using a 2-way coupling FSI approach for modeling nanofluid-based PVT systems. Five output responses electrical power, thermal power, electrical exergy, thermal exergy, and entropy generation are chosen against four input parameters, solar radiation (G_sun), ambient temperature (Tamb), mass flow rate (ṁ), and nanoparticles concentration % (φ) to analyze system performance. A statistical prediction model is developed using response surface methodology (RSM) that starts from the design of experiment (DOE). The predicted outcomes obtained from the statistical model and the numerical simulation of the heat transfer model exhibit the existence of good fitness. Furthermore, optimization is performed using RSM for various optimization objectives to suggest the ideal design parameter values for optimal system performance. Sensitivity analysis illustrates that a rise in ambient temperature causes a drop in electrical power production and leads to an increase in thermal power. However, the increase in solar radiation boosts electrical power and causes a drop in thermal exergy, entropy generation increases with an increase in solar irradiation. Similarly, an increase in mass flow rate leads to an increase in thermal power. Multi-objective optimization with the highest composite desirability values depicts the influence of input design parameters and has a favorable effect on the objective of concurrently maximizing electrical and thermal power.

Impact of pH and ZnO NPs on the fabricated PVA-PVP/ZnO nanofibers: Morphology, absorption behavior, anticancer, and antibacterial activity

In this study, a cost-effective hydrothermal method was successfully used to synthesize ZnO NPs at different pH levels (8, 10, and 12). Nanofibers were produced from polymeric blends PVA-PVP and PVA-PVP/ZnO nanocomposite precursor through electrospinning. XRD analysis revealed the hexagonal wurtzite structure of the synthesized ZnO NPs, with the dominant crystal plane (101). The impact of pH variation was evident in the increased intensity values of the peaks corresponding to (100), (002), and (101) planes as pH levels rose. The average crystallite size decreased from 31.4 to 27.0 nm using Scherrer's calculation, while the microstrain increased from 11.2 to 12.4 ×10−4 as the pH increased from 8 to 12. As wellas the average particle size of the ZnO NPs decreased from 75.05 to 51.35 nm with increasing pH levels, as depicted in FESEM images. The PVA-PVP/ZnO electrospun nanofibers exhibited smooth surfaces and uniform structures, with average diameters of 80.14, 93.33, and 124.13 nm for pH 8, 10, and 12, respectively. The calculation of the optical energy gap using the ASF approach closely matched Tauc's model, ranging from 3.57 to 3.20 eV. Evaluation of the anticancer activity of the nanofibers against MCF-7 cells showed an increase in cytotoxicity from 18 to 64 % with varying concentrations of ZnO NPs ranging from 6.25 to 100 μg/ml. The highest inhibitory effect (about 16 mm) was observed at pH 12 against gram-positive (Staphylococcus aureus).

Utilization of torrefied date stones with synthesized TiO2 nanoparticles for promoting humidity sensing of PVA/PVP nanocomposites for smart food packaging and biomedical applications

Fabricating smart and active packaging films with affordable cost has become the first demand for serving to market needs, particularly after COVID-19 disaster, for ensuring food security. Therefore, the broader goal of this work was to improve intelligent and active packaging films having humidity-sensing and antibacterial properties for biodegradable poly vinyl alcohol (PVA)/Polyvinylidene (PVP) reinforced with torrefied date stones (DS) and lethal amounts of TiO2 nanoparticles by a solvent-casting approach. Various concentrations of TiO2 NPs (i.e. 0.05, 0.15, and 0.30 %) in presence of 10 % torrefied DS (biochar) as a fixed content were used to fabricate PVA/PVP nanocomposite films. FT-IR spectra were utilized to monitor the DS functional groups before and after torrefaction at 270 °C. The crystal structure of synthesized TiO2 NPs as well as its impact on the PVA/PVP nanocomposites were verified by X-ray diffraction (XRD). The XRD micrographs and FT-IR spectra-based biofilms showcased that the degree of crystallinity and dispersibility of filler in the blend matrix were promoted, when the nanoparticles added. This was evidenced by SEM images. Mechanical testing also manifested that a great improvement in the tensile properties were noticed, especially at 0.30 % NPs and found the tensile strength reached ∼33 MPa compared to PVA/PVP blank (∼23.70 MPa) or PVA/PVP-BC (∼18.20 MPa). The humidity sensing properties were performed over a wide span of relative humidity from (11–97 % RH) and frequency (50 Hz-10 kHz). The data manifested that 100 Hz was the optimum testing frequency. Moreover, the gotten findings from humidity-sensing tests at 100 Hz exhibited that the sensor containing 0.15 % TiO2 NPs had higher sensitivity and could be considered as a nano-sensor for smart food packaging. Furthermore, the impact of TiO2 NPs on antibacterial activity was investigated to probably use these films in active packaging with prolonged shelf-life of food products and other promising applications including biological area.

A comparative analysis of the antimicrobial efficacy of different concentrations of silver nanoparticles and chlorhexidine against Enterococcus faecalis - In vitro study

Introduction: Root canal irrigants combat endodontic microbial flora, effectively targeting resilient microbes like Enterococcus faecalis, which persist despite treatment. Chlorhexidine (CHX), as an irrigant, boasts broad-spectrum antibacterial activity, notable substantivity in dentine, and favorable biocompatibility. In the realm of nanotechnology, the use of silver nanoparticle (AgNP) solutions appears promising, given their strong antibacterial and antimicrobial properties. Objective: The objective of the study was to compare the antimicrobial effectiveness of varying concentrations (1%, 0.75%, and 0.5%) of AgNPs and 2% CHX against E. faecalis. Materials and Methods: Four irrigant solutions, including 1%, 0.75%, and 0.5% AgNPs and 2% CHX with gentamicin as the control, will be assessed. The ATCC 29212 strain of E. faecalis will be cultivated at 37°C on brain–heart infusion Broth plates. After 48 h, the bacterial population will be quantified by counting colony-forming units on agar plates. Each irrigant will be applied to the plates, and the resulting bacterial inhibition zone will be measured. Results: Our study demonstrates the antimicrobial effects of 1%, 0.75%, and 0.5% AgNPs and 2% CHX against E. faecalis. While 2% CHX exhibited superior activity, AgNPs at various concentrations also displayed inhibitory effects against E. faecalis. Conclusion: In conclusion, this study highlights the antimicrobial properties of 1%, 0.75%, and 0.5% AgNPs and 2% CHX against E. faecalis. The results indicate that 2% CHX exhibits superior activity, while AgNPs at various concentrations also demonstrate inhibitory zones against E. faecalis.

Chitosan and Hyaluronic Acid Nanopolyelectrolyte Combined with Tanshinone IIA Targets Signal Transduction Pathway to Prevent Atherosclerosis

The purpose of this study was to evaluate the in vitro target impact of manufactured nanocarriers on vascular endothelial cells, as well as the effect of stable concentration and physicochemical properties of chitosan and hyaluronic acid nanoparticles loaded with tanshinone IIA, on the successful adsorption of targeting antibody. Polyelectrolyte composite nanoparticles were prepared by neutralizing chitosan (CS) and hyaluronic acid (HA). Anti-atherosclerosis antibody was quantitatively adsorbed on CS-HA nanoparticles after 4 h in water or PBS. Nanocarriers created in a lab are put through in vivo and in vitro tests on vascular endothelial cells and atherosclerotic plaques. Complexation and physicochemical properties of colloids were affected by external factors including charge mixing ratio and polymer content. The aforementioned method was used to produce non-stoichiometric CS-HA nano-colloids that were stable in water or PBS (pH 7.4) for over a month. Its morphology was analyzed using a scanning electron microscope. Nanoparticles of the CS-HA/CD47 antibody have a positive Zeta potential. Using this nanocarriers in vivo adsorbed to endothelial cells and plaques quite efficiently. Chitosan and hyaluronic acid nanopolyelectrolyte combined with tanshinone IIA nanoparticles were successfully synthesized. Customized nanocarriers may adsorb to endothelial cell lines and atherosclerotic plaques in vitro.