A comprehensive study of Al-Cu-Mg system reinforced with nano-ZrO2 particles synthesized by powder metallurgy technique.

More focus has recently been placed on enhancing the strength, elastic modulus, coefficient of thermal expansion (CTE), wear and corrosion resistance, and other qualities of aluminum (Al) alloys by varying the quantity of ceramics added for a range of industrial uses. In this regard, Al-4.2-Cu-1.6Mg matrix nanocomposites reinforced with nano-ZrO2 particles have been created using the powder metallurgy approach. The microstructure and particle size distributions of the produced powders were analyzed using a diffraction particle size analyzer, XRD, TEM, and SEM. To achieve good sinterability, the powders were compacted and sintered in argon. The sintered nanocomposites' mechanical, elastic, and physicochemical characteristics were measured. Additionally, the behavior of corrosion, wear, and thermal expansion were examined. The results showed a decrease in the particle sizes of the Al-Cu-Mg alloy by adding ZrO2 nanoparticles up to 45.8 nm for the composite containing 16 wt.% ZrO2. By increasing the sintering temperature to 570 °C, the densification of nanocomposites was enhanced. Also, the coefficient of thermal expansion and wear rate remarkably decreased by about 28 and 37.5% by adding 16 wt.% ZrO2. Moreover, microhardness yield, strength, and Young's modulus were enhanced to 161, 145, and 64%, respectively, after adding 16 wt.% ZrO2. In addition, increasing the exposure time was responsible for decreasing the corrosion rate for the same sample.

Electrothermal transport of water conveying copper, silver and alumina nanoparticles through a vertical wavy microchannel.

This study emphasizes the significance of optimizing heat transmission, energy conversion, and thermal management in electronic devices, renewable energy systems, and emerging technologies like thermoelectric devices and energy storage systems. The aim is to enhance heat transfer efficiency for improved performance and lifespan of electronic equipment. The research utilizes a mathematical flow analysis to study a water-based ternary nanofluid's flow and thermal characteristics in a vertical microfluidic channel driven by peristalsis and electroosmosis. The ternary-hybrid nanofluid (THNF), comprising copper, silver, and alumina nanoparticles dissolved in water, is examined considering induced magnetic fields. The study delves into fluid flow, heat absorption, and mixed convection, using Debye-Hückel, lubrication, and long wavelength approximations. Results show that THNF exhibits superior heat transmission compared to pure water. Increasing solid volume fraction of nanoparticles decreases THNF's temperature. Induced magnetic fields impact the system. This research could influence thermal pipe heat sinks and bioengineered medical devices design.

Surfactin-Conjugated Silver Nanoparticles as an Antibacterial and Antibiofilm Agent against Pseudomonas aeruginosa.

The emergence of antimicrobial resistance is an alarming global health concern and has stimulated the development of novel functional nanomaterials to combat multi-drug-resistant (MDR) bacteria. In this work, we demonstrate for the first time the synthesis and application of surfactin-coated silver nanoparticles as an efficient antibacterial and antibiofilm agent against the drug-resistant bacteria Pseudomonas aeruginosa for safe dermal applications. Our in vivo studies showed no significant superficial dermal irritation, edema, and erythema, while microscopic analysis revealed that surfactin-coated silver nanoparticles caused no pathological alterations at the applied concentrations. These results support the potential use of surfactin-coated silver nanoparticles against drug-resistant bacterial biofilm infections and in skin wound dressing applications.

Concomitant Effect of Quercetin and Its Copper Complex in the Development of Sustained-Release Nanoparticles of Polycaprolactone, Used for the Treatment of Skin Infection.

The study aimed to improve the treatment of impetigo with naturally occurring quercetin and its copper-quercetin (Cu-Q) complex by preparing sustained-release (SR) nanoparticles of polycaprolactone (PCL). The solvent evaporation method was used for the copper-quercetin (Cu-Q) complex formation, and their PCL nanoparticles (PCL-NPs, Q-PCL-NPs, and Cu-Q-PCL-NPs) were prepared by the high-pressure homogenization method. Synthesis of nanoparticles was confirmed by their physicochemical and antibacterial properties of quercetin against Gram-positive as well as Gram-negative bacteria. The percentage loading efficiency of quercetin and release in 100 mM of phosphate buffer pH 7.4 and 5.5 at 37 °C was found to be more than 90% after 24 h with the zero-order release pattern. Minimum inhibitory concentration of nanoparticles was found to increase threefold in the case of Cu-Q-PCL-NPs may be due to the synergistic antibacterial behavior. Scanning electron microscopy showed spherical nanoparticles, and surface roughness was confirmed by atomic force microscopy analysis. Fortunately, no sign of irritation on rat skin even at 3%, was seen. In vitro antioxidant assay by 2,2-diphenyl-1-picrylhydrazyl reduction was found to be ≤80 ± 0.02% which confirmed their scavenging activity. Interestingly, for the ex vivo study, the tape-stripping model was applied against Staphylococcus aureus containing rats and showed the formation of the epidermal layer within 4-5 days. Confirmation of antibacterial activity of pure quercetin, from Cu-Q complex, and their SR release from Q-PCL-NPs and Cu-Q-PCL-NPs was considered an effective tool for the treatment of skin diseases and can be used as an alternative of already resistant ciprofloxacin in impetigo.

A perspective of the prevalent H9N2 virus with a special focus on molecular and pathological aspects in commercial broiler chicken in Punjab, Pakistan.

Frequent outbreaks of avian influenza H9N2 virus in Pakistan revealed that this subtype has become endemic in the poultry industry and, besides economic losses, poses a threat to public health. The present study describes the molecular characterization and pathological alterations in naturally infected broiler chickens with the current H9N2 field strain and their phylogenomic dynamics. In this study, tissue samples (trachea, lung, kidney and intestine) from 100 commercial chicken flocks were collected from July 2018 to August 2019. Samples were subjected to molecular detection, phylogeny and subsequent pathological examination. The complete length of the HA gene was successfully amplified in five samples. Nucleotide sequencing revealed positive samples placed in a clade belonging to the B2 sub-lineage of the G1 genotype and categorized as LPAIV based on the amino acid sequence of the HA gene at the cleavage site (PAKSSR/G). Genetic analysis of the haemagglutinin (HA) gene revealed nt: 80.5%-99.5%; aa: 83.8%-98.9% homology to H9N2 strains reported previously from Pakistan, neighbouring countries, and (A/Quail/Hong Kong/G1/97). Gross lesions include a slight airsacculitis, mild hemorrhages, diffuse congestion and purulent exudate in tracheal mucosa, fibrinonecrotic cast in the trachea lumen and mild pulmonary congestion. Histopathological alterations include sloughing of epithelial cells and infiltration of inflammatory cells in the trachea, mononuclear cells (MNCs) infiltration, pulmonary congestion and exudate in the lumen of parabronchi, peritubular congestion in the kidneys with degeneration of tubular epithelial cells and degenerative changes in the intestinal villi epithelial cells and goblet cell hyperplasia. Immunohistochemistry analysis confirmed the presence of AIVH9N2 antigen in the trachea, lungs, kidney and intestine. Electron microscopy revealed ultrastructural changes in the trachea, including degenerated cilia, mitochondrial swelling and enlarged endoplasmic reticulum. Based on all essential analysis, the present study revealed the distribution of the H9N2 virus of G1 genotype in Punjab, Pakistan, with mild to moderate pathogenicity.

Biofunctionalized Nano-antimicrobials - Progress, Prospects and Challenges.

The rapid emergence of multidrug-resistant bacterial strains highlights the need for the development of new antimicrobial compounds/materials to address associated healthcare challenges. Meanwhile, the adverse side effects of conventional antibiotics on human health urge the development of new natural product-based antimicrobials to minimize the side effects. In this respect, we concisely review the recent scientific contributions to develop natural product-based nano-antibiotics. The focus of the review is on the use of flavonoids, peptides, and cationic biopolymer functionalized metal/metal oxide nanoparticles as efficient tools to hit the MDR bacterial strains. It summarizes the most recent aspects of the functionalized nanoparticles against various pathogenic bacterial strains for their minimal inhibitory concentrations and mechanism of action at the cellular and molecular levels. In the end, the future perspectives to materialize the in vivo applications of nano-antimicrobials are suggested based on the available research.

Supramolecular lipid nanoparticles as delivery carriers for non-invasive cancer theranostics.

Nanotheranostics is an emerging frontier of personalized medicine research particularly for cancer, which is the second leading cause of death. Supramolecular aspects in theranostics are quite allured to achieve more regulation and controlled features. Supramolecular nanotheranostics architecture is focused on engineering of modular supramolecular assemblies benefitting from their mutable and stimuli-responsive properties which confer an ultimate potential for the fabrication of unified innovative nanomedicines with controlled features. Amalgamation of supramolecular approaches to nano-based features further equip the potential of designing novel approaches to overcome limitations seen by the conventional theranostic strategies, for curing even the lethal diseases and endowing personalized therapeutics with optimistic prognosis, endorsing their clinical translation. Among many potential nanocarriers for theranostics, lipid nanoparticles (LNPs) have shown various promising advances in theranostics and their formulation can be tailored for several applications. Despite the great advancement in cancer nanotheranostics, there are still many challenges that need to be highlighted to fill the literature gap. For this purpose, herein, we have presented a systematic overview on the subject and proposed LNPs as the potential material to manage cancer via non-invasive approaches by highlighting the use of supramolecular approaches to make them robust for cancer theranostics. We have concluded the review by entailing the future perspectives of lipid nanotheranostics towards clinical translation.

Novel Cu/Zn Reinforced Polymer Composites: Experimental Characterization for Radiation Protection Efficiency (RPE) and Shielding Properties for Alpha, Proton, Neutron, and Gamma Radiations.

In this study, brass (Cu/Zn) reinforced polymer composites with different proportions of brass powders were fabricated. Different types of nuclear shielding parameters such as mass and linear attenuation coefficients, radiation protection efficiency, half and tenth value layers, and effective atomic number values were determined experimentally and theoretically in the energy range of 0.060-1.408 MeV in terms of gamma-ray shielding capabilities of fabricated polymer composites. A high Purity Germanium detector (HPGe) in conjunction with a Multi-Channel Analyzer (MCA) and twenty-two characteristic gamma-ray energies have been used in the experimental phase. In addition, the exposure and energy absorption buildup factors of reinforced Cu/Zn composites were calculated, and relative dose distribution values were computed to verify them. Proton mass stopping power (ΨP), proton projected range (ΦP), alpha mass stopping power (ΨA), and alpha projected range (ΦA) parameters, which indicate the interactions of the produced composites with charged particle radiation, were investigated. Fast neutron removal cross-section (ΣR) results were determined to give an idea in terms of neutron shielding. According to the obtained results, it is reported that the CuZn20 coded sample's ability to attenuate gamma-ray and charged particle radiation is more efficient than that of other prepared composites. A CuZn05 coded sample was found to be more suitable for neutron shielding capability.

Development of a LAMP assay using a portable device for the real-time detection of cotton leaf curl disease in field conditions.

Cotton production is seriously affected by the prevalent cotton leaf curl disease (CLCuD) that originated from Nigeria (Africa) to various parts of Asia including Pakistan, India, China and Philippines. Due to CLCuD, Pakistan suffers heavy losses approximately 2 billion USD per annum. Numerous reports showed that CLCuD is associated with multiple species of begomoviruses, alphasatellites and a single species of betasatellite, that is 'Cotton leaf curl Multan betasatellite' (CLCuMuB). The most prevalent form of CLCuD is the combination of 'Cotton leaf curl Kokhran virus'-Burewala strain (CLCuKoV-Bur) and CLCuMuB. Thus, the availability of an in-field assay for the timely detection of CLCuD is important for the control and management of the disease. In this study, a robust method using the loop-mediated isothermal amplification (LAMP) assay was developed for the detection of CLCuD. Multiple sets of six primers were designed based on the conserved regions of CLCuKoV-Bur and CLCuMuB-ßC1 genes. The results showed that the primer set targeting the CLCuMuB-ßC1 gene performed best when the LAMP assay was performed at 58°C using 100 ng of total plant tissue DNA as a template in a 25 µl reaction volume. The limit of detection for the assay was as low as 22 copies of total purified DNA template per reaction. This assay was further adapted to perform as a colorimetric and real-time LAMP assay which proved to be advantageously applied for the rapid and early point-of-care detection of CLCuD in the field. Application of the assay could help to prevent the huge economic losses caused by the disease and contribute to the socio-economic development of underdeveloped countries.

The Development of Antibiotics Based on Nanostructured Manganese Oxide; Understanding Mechanism from Fundamental Aspects to Application.

The emergence of bacterial resistance to currently available antibiotics emphasized the urgent need for new antibacterial agents. Nanotechnology-based approaches are substantially contributing to the development of effective and better-formulated antibiotics. Here, we report the synthesis of stable manganese oxide nanostructures (MnO NS) by a facile, one-step, microwave-assisted method. Asprepared MnO NS were thoroughly characterized by atomic force microscopy (AFM), field emission scanning electron microscopy (FESEM), dynamic light scattering (DLS), UV-Visible spectroscopy and X-ray powder diffraction (XRD). UV-Visible spectra give a sharp absorption peak at a maximum wavelength of 430 nm showed surface plasmon resonance (SPR). X-ray diffraction (XRD) profile demonstrated pure phase and crystalline nature of nanostructures. Morphological investigations by a scanning electron microscope showed good dispersity with spherical particles possessing a size range between 10-100 nm. Atomic force microscope data exhibited that the average size of MnO NS can be controlled between 25 nm to 150 nm by a three-fold increment in the amount of stabilizer (o-phenylenediamine). Antimicrobial activity of MnO NS on both gram-positive (Bacillus subtilis) and gram-negative (Escherichia coli) bacterial strains showed that prepared nanostructures were effective against microorganisms. Further, this antibacterial activity was found to be dependent on nanoparticles (NPs) size and bacterial species. These were more effective against Bacillus subtilis (B. subtilis) as compared to Escherichia coli (E. coli). Considering the results together, this study paves the way for the formulation of similar nanostructures as effective antibiotics to kill other pathogens by a more biocompatible platform. This is the first report to synthesize the MnO NS by green approach and its antibacterial application.

Electrothermal transport of third-order fluids regulated by peristaltic pumping.

The study of heat and electroosmotic characteristics in the flow of a third-order fluid regulated by peristaltic pumping is examined by using governing equations, i.e., the continuity equation, momentum equation, energy equation, and concentration equation. The wavelength is considered long compared to its height and a low Reynolds number is assumed. The velocity slip condition is employed. Analytical solutions are performed through the perturbation technique. The expressions for the dimensionless velocity components, temperature, concentration, and heat transfer rate are obtained. Pumping features were computed numerically for discussion of results. Trapping and heat transfer coefficient distributions were also studied graphically. The findings of the present study can be applied to design biomicrofluidic devices like tumor-on-a-chip and organ-on-a-chip.

Stimuli-activatable nanomedicines for chemodynamic therapy of cancer.

Chemodynamic therapy (CDT) takes the advantages of Fenton-type reactions triggered by endogenous chemical energy to generate highly cytotoxic hydroxyl radicals. As a novel modality for cancer treatment, CDT shows minimal invasiveness and high tumor specificity by responding to the acidic and the highly concentrated hydrogen peroxide microenvironment of tumor. The CDT approach for spatiotemporal controllable reactive oxygen species generation exhibits preferable therapeutic performance and satisfying biosafety. In this review article, we summarized the recent advances of stimuli-activatable nanomedicines for CDT. We also overviewed the strategies for augmenting CDT performance, including increasing the catalytic efficacy through rational design of the nanomaterials, modulating the reaction condition, inputting external energy field, and regulating the tumor microenvironment. Furthermore, we discussed the potential and challenges of stimuli-activatable nanomedicine for clinical translation and future development of CDT. This article is categorized under: Therapeutic Approaches and Drug Discovery > Nanomedicine for Oncologic Disease Nanotechnology Approaches to Biology > Nanoscale Systems in Biology Diagnostic Tools > In Vivo Nanodiagnostics and Imaging.

Design of heterostructured hybrids comprising ultrathin 2D bismuth tungstate nanosheets reinforced by chloramphenicol imprinted polymers used as biomimetic interfaces for mass-sensitive detection.

Combining nanomaterials in varying morphology and functionalities gives rise to a new class of composite materials leading to innovative applications. In this study, we designed a heterostructured hybrid material consisting of two-dimensional bismuth nanosheets augmented by molecularly imprinted networks. Antibiotic overuse is now one of the main concerns in health management, and their monitoring is highly desirable but challenging. So, for this purpose, the resulting composite interface was used as a transducer for quartz crystal microbalances. The main objective was to develop highly selective mass-sensitive sensor for chloramphenicol. Morphological investigation revealed the presence of ultrathin, square shaped nanosheets, 2-3 nm in height and further supplemented by imprinted polymers. Sensor responses are described as the decrease in the frequency of microbalances owing to chloramphenicol re-binding in the templated cavities, yielding a detection limit down to 0.74 µM. This sensor demonstrated a 100 % specific detection of chloramphenicol over its interfering and structural analogs (clindamycin, thiamphenicol, and florfenicol). This composite interface offers the advantage of selective binding and excellent sensitivity due to special heterostructured morphology, in addition to benefits of robustness and online monitoring. The results suggest that such composite-based sensors can be favorable platforms, especially for commercial prospects, to obtain selective detection of other biomolecules of clinical importance.

Nanoparticles-assisted delivery of antiviral-siRNA as inhalable treatment for human respiratory viruses: A candidate approach against SARS-COV-2.

The current pandemic of coronavirus disease 2019 (COVID-19) caused by severe acute respiratory syndrome coronavirus-2 (SARS-CoV-2) has challenged healthcare structures across the globe. Although a few therapies are approved by FDA, the search for better treatment options is continuously on rise. Clinical management includes infection prevention and supportive care such as supplemental oxygen and mechanical ventilatory support. Given the urgent nature of the pandemic and the number of companies and researchers developing COVID-19 related therapies, FDA has created an emergency program to move potential treatments with already approved drugs to patients as quickly as possible in parallel to the development of new drugs that must first pass the clinical trials. In this manuscript, we have reviewed the available literature on the use of sequence-specific degradation of viral genome using short-interfering RNA (siRNA) suggesting it as a possible treatment against SARS-CoV-2. Delivery of siRNA can be promoted by the use of FDA approved lipids, polymers or lipid-polymer hybrids. These nanoparticulate systems can be engineered to exhibit increased targetability and formulated as inhalable aerosols.

Synthesis of SPIONs-CNT Based Novel Nanocomposite for Effective Amperometric Sensing of First-Line Antituberculosis Drug Rifampicin.

It is necessary to study the possible interactions among various chemical surfaces and analytes before applying them to biological systems. We report the synthesis of carbon nanotubes-iron oxide (SPIONs-CNT) nanocomposite material by using lecithin stabilized superparamagnetic iron oxide nanoparticles (SPIONs) obtained by facile hydrothermal technique. Various characterizations of the obtained nanocomposite were carried out and electrochemical studies were performed further to study the interaction capabilities of the nanocomposite with anti-TB drug Rifampicin. Obtained results by cyclic voltammetric studies of SPIONs-CNT nanocomposite with limit of detection (LOD) of 1.178 µM showed the enhanced electrochemical sensitivity and selectivity of anti-tuberculosis (anti-TB) drug Rifampicin (RIF).

High molecular weight cross linked chitosan nanoparticles for controlled release of 5-Fluorouracil; Enhances its bioavailability.

The aim of study was cross linking of high molecular weight chitosan nanoparticles containing 5-fluorouracil to improve dissolution rate and ultimately enhance its bioavailability by reverse emulsion/micelles method and cross-linking agent i.e. glutaraldehyde (GA 25% aqueous solution in water). The nature and outer morphologies were evaluated by scanning electron microscopy (SEM). Drug release models were functional to support way from cross linked NPs. Cross linking of 5-fluorouracil with glutaraldehyde improved dissolution rate. Mean dissolution time of 5-fluorouracil decreased significantly upon reverse emulsion/cross linking as encapsulated drug is protective and thermally stable within cross linked chitosan NPs. FTIR studies showed formation of intermolecular hydrogen bonding between 5-fluorouracil and GA-co-CHNPs. DSC studies indicated a less crystalline state of 5-fluorouracil in cross linking. SEM showed spherical nanoparticles with somewhat rough surface. 5-FU release followed Korsmeyer-Peppas model which indicate diffusion and dissociation control drug release from GA-co-CH-NPs. 5-FU cross linked chitosan nanoparticles can be safe and useful tool for other chemotherapeutic agents.

Enzyme Immobilization on Metal-Organic Framework (MOF): Effects on Thermostability and Function.

MOFs are porous materials with adjustable porosity ensuing a tenable surface area and stability. MOFs consist of metal containing joint where organic ligands are linked with coordination bonding rendering a unique architecture favouring the diverse applications in attachment of enzymes, Chemical catalysis, Gases storage and separation, biomedicals. In the past few years immobilization of soluble enzymes on/in MOF has been the topic of interest for scientists working in diverse field. The activity of enzyme, reusability, storage, chemical and thermal stability, affinity with substrate can be greatly improved by immobilizing of enzyme on MOFs. Along with improvement in enzymes properties, the high loading of enzyme is also observed while using MOFs as immobilization support. In this review a detail study of immobilization on/in Metalorganic Frameworks (MOFs) have been described. Furthermore, strategies for the enzyme immobilization on MOFs and resulting in improved catalytic performance of immobilized enzymes have been reported.

In-situ synthesis of 3D ultra-small gold augmented graphene hybrid for highly sensitive electrochemical binding capability.

The fascinating properties of graphene can be augmented with other nanomaterials to generate hybrids to design innovative applications. Contrary to the conventional methodologies, we showed a novel yet simple, in-situ, biological approach which allowed for the effective growth of gold nanostructures on graphene surfaces (3D Au NS@GO). The morphology of the obtained hybrid consisted of sheets of graphene, anchoring uniform dispersion of ultra-small gold nanostructures of about 2-8 nm diameter. Surface plasmon resonance at 380 nm confirmed the nano-regimen of the hybrid. Fourier transform infrared spectroscopy indicated the utilization of amine spacers to host gold ions leading to nucleation and growth. The exceptional positive surface potential of 55 mV suggest that the hybrid as an ideal support for electrocatalysis. Ultimately, the hybrid was found to be an efficient receptor material for electrochemical performance towards the binding of uric acid which is an important biomolecule of human metabolism. The designed material enabled the detection of uric acid concentrations as low as 30 nM. This synthesis strategy is highly suitable to design new hybrid materials with interesting morphology and outstanding properties for the identification of clinically relevant biomolecules.

Assessment of Antimicrobial Features of Selenium Nanoparticles (SeNPs) Using Cyclic Voltammetric Strategy.

The emerging biomedical applications of selenium nanoparticles (SeNPs) require facile and efficient strategy to assess its interactions with cell membrane. In this study, an efficient and reproducible microwave assisted method was used to synthesize SeNPs with controllable size distributions. The physical properties of the emergent structures, such as morphology, structure, and size were studied. The antimicrobial applications of SeNPs were assessed by electrochemical analyses that entailed the systematic acquisition of cyclic voltammetry data. Our results demonstrate a straightforward method to predict the integrity of bacterial cell membranes following the administration of SeNP treatments.

Facile in situ generation of bismuth tungstate nanosheet-multiwalled carbon nanotube composite as unconventional affinity material for quartz crystal microbalance detection of antibiotics.

Overuse and thus a constant presence of antibiotics leads to various environmental hazards and health risks. Thus, accurate sensors are required to determine their presence. In this work, we present a mass-sensitive sensor for the detection of rifampicin. We chose this molecule as it is an important antibiotic for tuberculosis, one of the leading causes of deaths worldwide. Herein, we have prepared a carbon nanotube reinforced with bismuth tungstate nanocomposite material in a well-defined nanosheet morphology using a facile in situ synthesis mechanism. Morphological characterization revealed the presence of bismuth tungstate in the form of square nanosheets embedded in the intricate network of carbon nanotubes, resulting in higher surface roughness of the nanocomposite. The synergy of the composite, so formed, manifested a high affinity for rifampicin as compared to the individual components of the composite. The developed sensor possessed a high sensitivity toward rifampicin with a detection limit of 0.16 µM and excellent specificity, as compared to rifabutin and rifapentine. Furthermore, the sensor yielded statistically good recoveries for the monitoring of rifampicin in human urine samples. This work opens up a new horizon for the exploration of unconventional nanomaterials bearing different morphologies for the detection of pharmaceuticals.