Charge Composition Research Articles

Nanoparticles in Plants: Uptake, Transport and Physiological Activity in Leaf and Root.

Due to their unique characteristics, nanoparticles are increasingly used in agricultural production through foliage spraying and soil application. The use of nanoparticles can improve the efficiency of agricultural chemicals and reduce the pollution caused by the use of agricultural chemicals. However, introducing nanoparticles into agricultural production may pose risks to the environment, food and even human health. Therefore, it is crucial to pay attention to the absorption migration, and transformation in crops, and to the interaction with higher plants and plant toxicity of nanoparticles in agriculture. Research shows that nanoparticles can be absorbed by plants and have an impact on plant physiological activities, but the absorption and transport mechanism of nanoparticles is still unclear. This paper summarizes the research progress of the absorption and transportation of nanoparticles in plants, especially the effect of size, surface charge and chemical composition of nanoparticle on the absorption and transportation in leaf and root through different ways. This paper also reviews the impact of nanoparticles on plant physiological activity. The content of the paper is helpful to guide the rational application of nanoparticles in agricultural production and ensure the sustainability of nanoparticles in agricultural production.

Sustainable charged composites with amphiphobic surfaces for harsh environment–tolerant non-contact mode triboelectric nanogenerators

In this work, the sustainable charged composites with amphiphobic surfaces are reported regarding harsh environment tolerance and robust contactless mode triboelectric nanogenerators (TENGs). SiO2 and polytetrafluoroethylene (PTFE) particles are well dispersed in thermoplastic polyurethane (TPU) and polydimethylsiloxane (PDMS), respectively. Both surfaces become very rough after a chemical etching method and the surface of PTFE-PDMS is fluorinated using a fluorinated alkylsilane, resulted in the formation of amphiphobic surfaces. This significantly enhances the environment tolerance of the contactless mode TENGs as well as the charge retention characteristics of the composites. As a practical non-contact mode application, a speed sensor fabricated using two composites can stably detect a low vehicle speed less than 3.75 km/h when exposed to high humidity (∼ 99%) and various chemical oils. Over 50% of initial output voltage are still generated after 2 weeks with no more decrease after 5 days, showing a 1.4 times slower charge decay rate, compared with the reference Ni-PTFE based TENG.

HIV-1 Gag specificity for PIP2 is regulated by macromolecular electric properties of both protein and membrane local environments

HIV-1 assembly occurs at the plasma membrane, with the Gag polyprotein playing a crucial role. Gag association with the membrane is directed by the matrix domain (MA), which is myristoylated and has a highly basic region that interacts with anionic lipids. Several pieces of evidence suggest that the presence of phosphatidylinositol-(4,5)-bisphosphate (PIP2) highly influences this binding. Furthermore, MA also interacts with nucleic acids, which is proposed to be important for the specificity of GAG for PIP2-containing membranes. It is hypothesized that RNA has a chaperone function by interacting with the MA domain, preventing Gag from associating with unspecific lipid interfaces. Here, we study the interaction of MA with monolayer and bilayer membrane systems, focusing on the specificity for PIP2 and on the possible effects of a Gag N-terminal peptide on impairing the binding for either RNA or membrane. We found that RNA decreases the kinetics of the protein association with lipid monolayers but has no effect on the selectivity for PIP2. Interestingly, for bilayer systems, this selectivity increases in presence of both the peptide and RNA, even for highly negatively charged compositions, where MA alone does not discriminate between membranes with or without PIP2. Therefore, we propose that the specificity of MA for PIP2-containing membranes might be related to the electrostatic properties of both membrane and protein local environments, rather than a simple difference in molecular affinities. This scenario provides a new understanding of the regulation mechanism, with a macromolecular view, rather than considering molecular interactions within a ligand-receptor model.

СИНТЕЗ СИАЛОНА ИЗ СВС-СИСТЕМЫ В РЕЖИМЕ ТВЕРДОПЛАМЕННОГО ГОРЕНИЯ

The study objective is to synthesize sialon powder in the mode of solid-flame combustion of silicon dioxide (sand) - sodium azide – silicon and aluminum halogenide systems.
 The task to which the paper is devoted is to find out the initial charge composition (choosing from several sand samples the best in terms of the amount of impurities and the gradation factor), which synthesis gives Si3Al3O3N5 sialon in the mode of solid-flame combustion.
 Research methods used to obtain and analyze the synthesized product in SHS-Az mode: self-propagating high-temperature synthesis using sodium azide and halogenides in SHS-Az laboratory reactor, X-ray fractional analysis on ARL X'trA-138 diffractometer and the study of microstructure by a scanning electron microscope JSM-6390A.
 The novelty of the work is in the fact that for the first time SHS-Az method is applied to conduct research on the synthesis of sialon from systems which use bank sand as silicon dioxide.
 The study results on the synthesis of sialon in the mode of solid-flame combustion show that the final product, in addition to β-Si3Al3O3N5 consists of some more phases such as Si3N4: AlN, Si, naf and Na3AlF6. It is found out that during combustion the formed uniform particles of the product are combined into agglomerate. The average size of the particles that make up the product is 180-230 nm.
 Conclusions: it is found out that Si3Al3O3N5 sialon is obtained in the mode of solid-flame combustion of silicon dioxide (sand) - sodium azide – silicon and aluminum halogenide systems.

Results of application of porous permeable SHS catalytic blocks in multistage converters, 
 diesel exhaust gases

BACKGROUND: According to the statements of leading experts in the diesel industry, in order to introduce standards for the levels of harmful emissions into the atmosphere, it is necessary to use particulate filters and catalytic converters, which will increase the efficiency of exhaust gas conversion and improve the environmental performance of diesel engines.
 AIMS: Educing harmful emissions into the atmosphere, improving the quality and reducing the cost of cleaning exhaust gases during the implementation of the life cycles of transport energy facilities by using porous SHS blocks in catalytic converters and particulate filters.
 METHODS: Stand tests of prototypes of neutralizers of the AltSTU design with one, two and three stages of purification were carried out. The first stage is a particulate filter made of porous permeable SHS material, the second stage is an oxidizing SHS block, the third stage is a catalytic reducing SHS block. To obtain catalytic blocks by the SHS method, the following charge composition was used: iron scale 18X2H4MA -47.5%; chromium oxide PH-1 according to TU 882-76 17.7%; nickel powder PNK-OT-1 according to GOST 9722-79 4.9%; aluminum powder according to TU 485-22-87 grade ASD-1 15%, copper 11%; aluminum oxide 3.8%; iridium 0.01%. The charge of the recovery unit consisted of 14.5% copper. The resulting blocks had a permeable structure and high strength. The average pore size was 180 microns. Neutralizers were installed butt-to-butt with a turbocharger.
 RESULTS: It was revealed that NOx emissions according to the load characteristic of the KamAZ-740 diesel engine at 2600 min-1 decrease at average effective pressures Pe equal to 0.03; 0.55; 0.77 MPa from 3.82...11.62...9.49 g/m3, respectively, to 3.23...6.52...4.61 g/m3 or approximately 13...44...53%. Reduction of emissions of solid particles at the same loads was 75; 45; 63%, of hydrocarbons 72; 53; 54%. The minimum specific fuel consumption was observed in the range of 1600...2000 min-1 according to the external speed characteristic. When using a neutralizer with two catalytic units installed in series, emissions from hydrocarbon exhaust decreased from 3.12...1.21 to 0.90...0.29 g/m3, or by 71...76%. The degree of CO conversion was 78...73%; NOx 4...52%, and the total purification coefficient was a coaxial installation of additional blocks made of SHS-catalytic materials has led to an improvement in the quality of cleaning up to =0,698. Over 360 hours of operation, the efficiency of PM conversion decreased from 55 to 45%, CO from 58 to 46%, NOx from 65 to 44%, which indicated the beginning of deactivation of catalysts.
 CONCLUSIONS: The use of multi-stage neutralizers with SHS-catalytic units can reduce emissions of hydrocarbons by 1.95 times, carbon monoxide by 3.6 times, nitrogen oxides by 2 times, solid particles by 3 times, ensuring compliance with Russian standards.

On the Seed Population of Solar Energetic Particles in the Inner Heliosphere

AbstractParticles measured in large gradual solar energetic particle events are believed to be predominantly accelerated at shocks driven by coronal mass ejections (CMEs). Ion charge state and composition analyses suggest that the origin of the seed particle population for the mechanisms of particle acceleration at CME‐driven shocks is not the bulk solar wind thermal material, but rather a suprathermal population present in the solar wind. This suprathermal population could result from remnant material accelerated in prior solar flares and/or preceding CME‐driven shocks. In this work, we examine the distribution of this suprathermal particle population in the inner heliosphere by combining a magnetohydrodynamic simulation of the solar wind and a Monte Carlo simulation of particle acceleration and transport. Assuming that the seed particles are uniformly distributed near the Sun by solar flares of various magnitudes, we study the longitudinal distribution of the seed population at multiple heliocentric distances. We consider a nonuniform background solar wind, consisting of fast and slow streams that lead to compression and rarefaction regions within the solar wind. Our simulations show that the seed population at a particular location (e.g., 1 au) is strongly modulated by the underlying solar wind configuration. Corotating interaction regions and merged interactions regions can strongly alter the energy spectra of the seed particle populations. In addition, cross‐field diffusion plays an important role in mitigating strong variations of the seed population in both space and energy.

Sandwich-like construction of a new aminated chitosan Schiff base for efficient removal of Congo red

Herein, a novel sandwich-like α-ketoglutaric acid Schiff base-aminated chitosan composite (α-kGl-AmCsSB) was fabricated by reacting α-ketoglutaric acid and aminated chitosan. The as-fabricated α-kGl-AmCsSB was inspected by diversified characterization tools to determine its morphology, surface charge, and chemical composition as well as define the linkage pathway between α-kGl and AmCs. The SEM images demonstrated a spongy network of AmCs with interconnected pores structure which turned to a quite rough surface due to the linkage of α-kGl to the free amine groups of AmCs. Notably, the XPS and FTIR spectra suggested the linkage of α-kGl to the amine group of AmCs. The experimental results implied the superior adsorption efficiency of Congo red (CR) onto α-kGl-AmCsSB since the maximum adsorption capacity (qmax) reached 434.78 mg/g at 25 °C and pH 3. Based on kinetics data, the adsorption of CR on α-kGl-AmCsSB followed pseudo-second-order model. Furthermore, D-R model infers that the CR adsorption onto α-kGl-AmCsSB occurred via physical interactions since the E value < 8 kJ/mol. The recyclability test was implemented for five cycles with R% > 72%. More importantly, the adsorption mechanism of CR onto α-kGl-AmCsSB was proposed and discussed. Ultimately, the novel sandwich-like α-kGl-AmCsSB exhibited advanced adsorption performance toward CR along with excellent reusability. Based on these results, we recommend more modifications on α-kGl-AmCsSB for exploiting its remarkable advantages and applying it on a large scale.

Магнитные свойства стекол, синтезированных на основе горных пород различного генезиса

The structural-phase, chemical composition and magnetic properties of artificial glasses obtained by high-temperature melting of rock mixtures of different genesis: volcanogenic-sedimentary rocks, quartzitic shales, psamite-silt-pelitic complexes were studied. Different in duration cooling and glass transition conditions were used for glass synthesis. The magnetic state of the iron-containing phase and the analysis of the presence and contribution of iron oxides to the magnetic properties were assumed to be the characteristic criterion determining the parameters of the glass formation process. It was shown that the total iron content in artificial glasses depends exclusively on the composition of the initial charge. In this case, the iron-containing component is mainly determined by sedimentary rocks. The formation of magnetic minerals is determined both by the composition of the charge and by the rate of cooling of the melt. During “fast” cooling, the formed magnetic particles are mostly (up to 90% or more of the total content of the magnetic phase in the sample) in a superparamagnetic state. During “slow” cooling, a mixture of particles of different sizes and, accordingly, in different magnetic states is formed: from superparamagnetic to low-domagnetic. The ferrimagnetic phase crystallizing in artificial glasses is represented by chemically heterogeneous aggregates of iron oxides, mainly non-stoichiometric magnetite.

The formation of alloy based on Al-Ti-B system by electroslag process involving dispersed engineering waste

In this article presents technological process of manufacturing Al-Ti-B rod master alloy by electroslag casting is proposed and investigated. Aluminum alloy chip waste of a grade AK7, commercial titanium of a grade VT1-00 and amorphous boron of a grade A were used as starting materials. The consumable electrode is a product in the form of a rod obtained by mouthpiece pressing of a mixture of crushed starting materials in a mass ratio of AK7 : VT1-00 : amorphous boron = 97:2:1. According to the proposed technology and the ratio of starting materials in the charge composition, an experimental bar material of the Al-Ti-B ligature was obtained, electron microscopic, micro-X-ray spectral studies, the stereometric analysis of the structure which showed the priority interaction of titanium with boron.

Insights into human eNOS, nNOS and iNOS structures and medicinal indications from statistical analyses of their interactions with bound compounds.

83 Structures of human nNOS, 55 structures of human eNOS, 13 structures of iNOS, and about 126 reported NOS-bound compounds are summarized and analyzed. Structural and statistical analysis show that, at least one copy of each analyzed compound binds to the active site (the substrate arginine binding site) of human NOS. And binding features of the three isoforms show differences, but the binding preference of compounds is not in the way helpful for inhibitor design targeting nNOS and iNOS, or for activator design targeting eNOS. This research shows that there is a strong structural and functional similarity between oxygenase domains of human NOS isoforms, especially the architecture, residue composition, size, shape, and distribution profile of hydrophobicity, polarity and charge of the active site. The selectivity and efficacy of inhibitors over the rest of isoforms rely a lot on chance and randomness. Further increase of selectivity via rational improvement is uncertain, unpredictable and unreliable, therefore, to achieve high selectivity through targeting this site is complicated and requires combinative investigation. After analysis on the current two targeting sites in NOS, the highly conserved arginine binding pocket and H4B binding pocket, new potential drug-targeting sites are proposed based on structure and sequence profiling. This comprehensive analysis on the structure and interaction profiles of human NOS and bound compounds provides fresh insights for drug discovery and pharmacological research, and the new discovery here is practically applied to guide protein-structure based drug discovery.

Added value of thermodynamic white-box data for HCCI combustion prediction

Homogeneous charge compression ignition (HCCI) is a promising combustion process to reducing both greenhouse gas and pollutant emissions in the transportation sector. The combustion starts when the thermodynamic state of the cylinder charge reaches the auto-ignition properties of the fuel, which is challenging to model. In addition, the strong cyclic coupling due to required exhaust gas recirculation leads to a significant dependence on the combustion of the previous cycle.This work focuses on identifying accurate models to predict the combustion process for potential use in an MPC. In this work HCCI is achieved using negative valve overlap (NVO) on a fully flexible valve train. The fluctuating composition and temperature of the cylinder charge is not directly measurable and not taken into account in state of the art approaches. It is assumed that it has a decisive influence on the start of combustion. Hence, in this work, the thermodynamic state is modeled by a detailed physical white-box model, which is used as an additional input for the combustion prediction. To investigate the added value of the thermodynamic state data, an Artificial neural network (ANN) is trained to predict combustion both with and without the thermodynamic state data from the white-box model. The root-mean-square error of the ANN including thermodynamic data is reduced by 12.7%. Thus, by adding the thermodynamic white-box data, the HCCI combustion prediction can be significantly improved.

Physical and mechanical properties of ceramic brick using rice husk and ash of thermal power plants

The paper presents the results of the influence on shrinkage deformations of the adopted composition during the drying and firing of ceramic bricks made using rice husk and ash of the combined heat and power plant of the city of Kyzylorda of the Republic of Kazakhstan. The optimal values of the husk additives content and ash from thermal power plants in the studied compositions were determined. Ash dumps from thermal power plants (TPP) create environmental tension and pose a great threat to both the environment and human health. It was found that the hydro-removal ash from the thermal power plant mainly consists of oxides of silica (45.45…46.37 %) and alumina (16.62…17.70 %), there are oxides of calcium (1.66…2.20 %), magnesium (0.86…1.12 %), iron (2.98…3.41 %) and alkali metals (0.80…1.04 %). The composition of ceramic bricks based on loess-like loam, rice husks, and ash from thermal power plants was studied. The charge composition of the raw components of the “clay, TPP ash, and rice husk” brick: clay is 71…75 %, TPP ash is 18…22 %, and rice husk is 2…6 % of the total mass of the components of the raw mixture of ceramic bricks. The compressive strength of fired ceramic bricks was 11…12 MPa. According to the results of experimental studies, it was found that the increased concentration of rice husks in natural mixtures is characterized by a stable increase in ceramic mass drying cracks. The increase in time until the appearance of drying cracks is 100 up to 160 sec. The resulting ceramic brick in accordance with the developed composition has a low weight, good thermal properties and meets the standard requirements for ceramic bricks according to GOST 530-2012

INFLUENCE OF THE DISPERSION ENVIRONMENT ON THE PROPERTIES OF THE CHARGE OF LEAD-TIN BRONZE

This article presents the results of a study of the properties of the electroerosive charge obtained from the waste of lead-tin bronze BrO5C25, in particular, the influence of the chemical composition of the dispersion medium on the elemental and phase composition of the resulting electroerosive particles is evaluated. It has been established that when carrying out experiments on obtaining a charge in an oxygen-containing liquid (distilled water), a part of oxygen is present on the surface of the obtained particles. According to the results of the experiment, it was found that the main elements in the charge obtained by the method of electroerosive dispersion of BrO5C25 lead bronze waste in distilled water are oxygen, copper, tin, zinc and lead. The remaining elements are distributed relatively evenly in the mixture. Based on the performed X-ray diffraction microanalysis, it was found that the main phases in the charge obtained in distilled water are Cu, Pb(Cu2O2), Pb5O8, Pb, Sn. When carrying out experiments to obtain a charge in a carbon-containing liquid (illuminating kerosene), a part of carbon is present on the surface of the obtained particles. According to the results of the experiment, it was found that the main elements in the charge obtained by the method of electroerosive dispersion of lead bronze waste BrO5C25 in lighting kerosene are carbon, copper, tin, zinc and lead. The remaining elements are distributed relatively evenly in the charge. Based on the performed X-ray diffraction microanalysis, it was found that there are no carbide-forming elements in the alloy. The main phases in the charge obtained in lighting kerosene are also Cu, Pb(Cu2O2), Pb5O8, Pb, Sn. Thus, the influence of the dispersion medium on the elemental and phase composition of the electroerosive charge of lead-tin bronze BrO5C25 has been established.

MAX phase Ti2AlN synthesis by reactive sintering in vacuum

The synthesis of MAX phase Ti2AlN from several mixtures of Ti, Al, TiN, and AlN powders by vacuum sintering of greensamples in the form of dense compacts, bulk powder in silica tubes, and plain layer in a closed rectangular molybdenum boat was studied upon variation in charge composition and sintering temperature Ts. The sintering of 2 : 1 Ti–AlN mixture was carried out at 1100, 1200, 1300, 1400, and 1500 °С with exposure time of 60 min. The largest MAX phase content (94 wt.%) was reached at Ts = 1400 °С. The sintering of 1 : 1 TiAl : TiN composition at the same temperature gave 93 wt.% Ti2AlN. The best result (singlephase Ti2AlN in a 100-% yield) was achieved upon the sintering of 1 : 1 : 1 Ti–Al–TiN composition at Ts = 1400 °С. The scalability of our process was checked by the fabrication of a large (0.5 kg) and uniform cake of single-phase Ti2AlN. In experiments we used green samples with shielded lateral surface (bulk powder in silica tubes, plain layer in a closed molybdenum boat) and without shield (dense compacts). It has been shown that shielding of Ti–Al–TiN samples restricts the escape of Al vapor from a sintered mixture, thus providing more favorable conditions for the synthesis of single-phase Ti2AlN. Our process can be readily recommended for practical implementation.

Effect of Chromium Carbide on the Structure of a Sprayed Metal upon Its Introduction into the Composition of a Filler Flux-Cored Wire Charge

Effect of Chromium Carbide on the Structure of a Sprayed Metal upon Its Introduction into the Composition of a Filler Flux-Cored Wire Charge

Acoustic plasmons and isotropic short-range interaction in two-component electron liquids

Dispersion of acoustic plasmons and isotropic Landau parameters are calculated in three- and two-dimensional two-component electron-electron and electron-hole liquids at various concentration and mass ratios using Landau-Silin kinetic equation and the random phase approximation for the self-energy. It is shown that the mode propagation and the strength of quasiparticle interaction are determined by the intercomponent screening and are asymmetric with respect to charge composition of two-component liquid. The well-defined acoustic plasmon-zero sound mode arises at strong difference in concentrations between components and its renormalization by the short-range exchange-correlation interaction is negligible. The acoustic plasmon mediated interparticle effective interaction in the fast component is weak in both the three- and two-dimensional electron liquids with parabolic dispersion, so the associated plasmonic superconductivity and the formation of acoustic plasmarons are unfavorable.

Impact of Charge Composition and Distribution on the Antibacterial Properties of Polypeptide Coatings.

Inspired by the charge composition and distribution of proteins and peptides, we designed and prepared a series of brush polypeptides with positive and negative charges separately distributed in the side chains and the backbones. The brush polypeptides can self- or co-deposit on various substrates forming ultrathin and stable coatings. They showed potent bactericidal activity and antibiofilm property, outperforming conventional linear polypeptide coatings with randomly distributed positive and negative charges. Keeping the balance of positive/negative charges and increasing the numbers of positive/negative charges can further improve the antibacterial property of brush polypeptide coatings without sacrificing their biocompatibility.

Development of optimal dinas ramming masses for lining of thermal units

The article presents the results of research on the development of optimal chemical, charge and fractional compositions of dinas ramming masses for lining of thermal units. It has been established that the best results, in terms of material composition and thermo mechanical properties, are dominated by prototypes based on quartzite, with a content of quartz sand and kaolin not higher than 20 wt. %. The possibilities of partial replacement of quartzite with quartz sand in the development of new compositions of dinas ramming masses are shown. Ill. 1. Ref. 15. Tab. 5.

Valuation of process efficiency of bauxite charge sintering furnace

PPeculiarities of change of its thermal operation using experimental data of thermal engineering studies are considered for evaluation of technological efficiency of rotary sintering furnace. It was found that the main material flows in the rotary sintering furnace are pulp consumption (47,65 %), as well as gaseous flows of air (48,90 %) and fuel combustion waste products (51,17 %) with process gases (18,01 %) and removal of physical moisture in the form of steam (12,34 %). Efficiency of solid charge components participation in the process is characterized by sinter (21,46 %), dust removal from the working space (1,71 %) and flow of recycled dust particles (0,96 %) and is due to limited heat exchange intensity in the working space. Comparative analysis of the parameters of gas flows at the outlet of the furnace indicates a low efficiency of using existing dust deposition equipment: a settling chamber of no more than 43,66 %, electrofilters of no more than 89,77‒90,00 %. To improve their performance, it is proposed to use acoustic intensification of the dust deposition process. Examination of material flows of sintering process indicates unsaturated composition of bauxite charge with possibility of limited development of exothermic reactions. When studying the articles of the thermal balance of the sintering furnace, a significant level of heat losses with sinter and with exhaust gases was established, which limits the total thermal efficiency of the unit to no more than 67,16 %..

Antimicrobial Activity of Azithromycin Encapsulated into PLGA NPs: A Potential Strategy to Overcome Efflux Resistance.

Antimicrobial resistance represents a public health problem with a major negative impact on health and socioeconomic development, and is one of the biggest threats in the modern era. This requires the discovery of new approaches to control microbial infections. Nanomedicine could be one of the promising strategies to improve the treatment of microbial infections. Polymer nanoparticles (PNPs) were reported to overcome the efflux-resistant mechanism toward chemotherapeutic agents. However, to the best of our knowledge, no studies were performed to explore their ability to overcome the efflux-resistant mechanism in bacteria. In the current study, azithromycin (AZI), a macrolide antibiotic, was encapsulated into a biocompatible polymer, poly (lactic-co-glycolic acid) (PLGA) using the nano-precipitation method. The effect of the drug to polymer ratio, surfactant, and pH of the aqueous medium on particle size and drug loading percentage (DL%) were investigated in order to maximize the DL% and control the size of NPs to be around 100 nm. The antibacterial activity of AZI-PLGA NPs was investigated against AZI-resistant bacteria; Methicillin-resistant Staphylococcus aureus (MRSA) and Enterococcus faecalis (E. faecalis), where the efflux mechanism was demonstrated to be one of the resistant mechanisms. AZI-PLGA NPs were safer than free AZI, as revealed from the cytotoxicity test, and were able to overcome the efflux-resistant mechanism, as revealed by decreasing the MIC of AZI-PLGA NPs by four times than free AZI. The MIC value reduced from 256 to 64 µg/mL and from >1000 to 256 µg/mL for MRSA and E. faecalis, respectively. Therefore, encapsulation of AZI into PNPs was shown to be a promising strategy to overcome the efflux-resistant mechanism towards AZI and improve its antibacterial effect. However, future investigations are necessary to explore the effect (if any) of particle size, surface charge, and material composition of PNPs on antibacterial activity. Moreover, it is essential to ascertain the safety profiles of these PNPs, the possibility of their large-scale manufacture, and if this concept could be extended to other antibiotics.