Antibacterial Nanoparticles Research Articles

Design of Ultrasound-Driven Charge Interference Therapy for Wound Infection.

Wound infections, especially those caused by pathogenic bacteria, present a considerable public health concern due to associated complications and poor therapeutic outcomes. Herein, we developed antibacterial nanoparticles, namely, PGTP, by coordinating guanidine derivatives with a porphyrin-based sonosensitizer. The synthesized PGTP nanoparticles, characterized by their strong positive charge, effectively disrupted the bacterial biosynthesis process through charge interference, demonstrating efficacy against both Gram-negative and Gram-positive bacteria. Additionally, PGTP nanoparticles generated reactive oxygen species under ultrasound stimulation, resulting in the disruption of biofilm integrity and efficient elimination of pathogens. RNA-seq analysis unveiled the detailed mechanism of wound healing, revealing that PGTP nanoparticles, when coupled with ultrasound, impair bacterial metabolism by interfering with the synthesis and transcription of amino acids. This study presents a novel approach to combatting wound infections through ultrasound-driven charge-interfering therapy, facilitated by advanced antibacterial nanomaterials.

Evaluation of antimicrobial and antioxidant effects of silver nanoparticles synthesized with leaves of Lepidium draba L.

Nanoscience is a prominent scientific field with great potential and many novel and cost-effective applications. Numerous green and environmentally friendly synthesis methods have been introduced that use different plant extracts to produce silver, gold, copper, and iron antibacterial nanoparticles. Plant extracts contain rejuvenating compounds which, when exposed to metal salts (in this research, silver nitrate), facilitate their reduction to metal ions. In the present investigation, Lepidium draba was used as a regenerating factor. Silver nanoparticles (AgNPs) containing Azmak leaf extract were synthesized under optimal conditions including silver nitrate concentration, time, temperature, and pH. These nanoparticles were then evaluated for their characteristics using transmission electron microscopy (TEM), Fourier transform infrared (FT-IR) spectroscopy, X-ray diffraction (XRD), dynamic light scattering (DLS), and zeta potential analyses. Subsequently, the antibacterial properties of nanoparticles were assessed using the broth microdilution method. The 2,2-diphenyl-1-picrylhydrazyl (DPPH) method was also employed to examine the antioxidant properties of synthesized nanoparticles. Structural analyses revealed the formation of spherical, stable, and pure AgNPs with a size of 20–35 nm. The synthesized AgNPs exhibited strong antibacterial activity against Gram-negative and Gram-positive bacteria. In addition, investigation of the antioxidant activity of the nanoparticles showed 89% inhibition at a concentration of 250 μg/mL. AgNPs synthesized using the Azmak leaf extract can be employed as low-cost and efficient nanoparticles for environmental and biomedical applications and their dual antimicrobial and antioxidant characteristics could potentially position them as candidates for treating infectious wound.

Effect of orthodontic adhesives modified with antibacterial nanoparticles on bond strength: literature review

Effect of orthodontic adhesives modified with antibacterial nanoparticles on bond strength: literature review

In vitro and in vivo investigation of antibacterial silver nanoparticles functionalized bone grafting substitutes.

Infection is a major concern in surgery involving grafting and should be considered thoroughly when designing biomaterials. There is considerable renewed interest in silver nanoparticles (AgNPs) owing to their ability to potentiate antibacterial properties against multiple bacterial strains. This study aimed to develop two antibacterial bone regenerative scaffolds by integrating AgNPs in bovine bone particles (BBX) (Product 1), and a light cross-linked hydrogel GelMA (Product 2). The constructs were characterized using scanning electron microscopy. Metabolic activity of osteoblasts and osteoclasts on the constructs was investigated using PrestoBlue™. Disk diffusion assay was conducted to test the antibacterial properties. The regenerative capacity of the optimized AgNP functionalized BBX and GelMA were tested in a rabbit cranial 6 mm defect model. The presence of AgNPs appears to enhance proliferation of osteoblasts compared to AgNP free controls in vitro. We established that AgNPs can be used at a 100 μg dose that inhibits bacteria, with minimal adverse effects on the bone cells. Our rabbit model revealed that both the BBX and GelMA hydrogels loaded AgNPs were biocompatible with no signs of necrosis or inflammatory response. Grafts functionalized with AgNPs can provide antibacterial protection and simultaneously act as a scaffold for attachment of bone cells.

Physiological Microenvironment Dependent Self-Cross-Linking of Multifunctional Nanohybrid for Prolonged Antibacterial Therapy via Synergistic Chemodynamic-Photothermal-Biological Processes.

Herein, a multifunctional nanohybrid (PL@HPFTM nanoparticles) was fabricated to perform the integration of chemodynamic therapy, photothermal therapy, and biological therapy over the long term at a designed location for continuous antibacterial applications. The PL@HPFTM nanoparticles consisted of a polydopamine/hemoglobin/Fe2+ nanocomplex with comodification of tetrazole/alkene groups on the surface as well as coloading of antimicrobial peptides and luminol in the core. During therapy, the PL@HPFTM nanoparticles would selectively cross-link to surrounding bacteria via tetrazole/alkene cycloaddition under chemiluminescence produced by the reaction between luminol and overexpressed H2O2 at the infected area. The resulting PL@HPFTM network not only significantly damaged bacteria by Fe2+-catalyzed ROS production, effective photothermal conversion, and sustained release of antimicrobial peptides but dramatically enhanced the retention time of these therapeutic agents for prolonged antibacterial therapy. Both in vitro and in vivo results have shown that our PL@HPFTM nanoparticles have much higher bactericidal efficiency and remarkably longer periods of validity than free antibacterial nanoparticles.

Amphiphilic N-halamine copolymer antibacterial nanoparticles with hydrogen-donor and hydrogen-acceptor

Bacterial contamination in water bodies is potentially transmissible to humans, making water bodies a major pathway of bacterial transmission. However, existing hydantoin copolymer nanoparticles did not achieve the regulation of nanoparticle dispersion and particle size by adjusting the ratio of hydrogen-donors and hydrogen-acceptors. To tackle this issue, amphiphilic hydantoin copolymer nanoparticles (P(VBDH-BA-NVP)NPs) were synthesized by modulating hydrogen-donors and hydrogen-acceptors using emulsion polymerization, and amphiphilic N-halamine copolymer nanoparticles (P(ClV-BA-NVP)NPs) were subsequently prepared via chlorination treatment. Impressively, nanoparticle dispersion and particle size were modulated by adjusting the ratio of hydrogen-donors and hydrogen-acceptors. With the increase of nanoparticle dispersion and the decrease of particle size, the active chlorine content was gradually enlarged, and the antibacterial performance was progressively enhanced against Escherichia coli (E. coli) and Staphylococcus aureus (S. aureus). More importantly, amphiphilic N-halamine copolymer nanoparticles with two-dimensional dispersing (2DD-P(ClV-BA-NVP)NPs) exhibited excellent antibacterial properties, which benefited from the dual coordination of direct contact killing and indirect release killing in aqueous medium. Through designing P(VBDH-BA-NVP)NPs with hydrogen bond interactions, this approach aims to achieve the constitutive relationship between the effective exposure of active sites and the antibacterial effect.

Polycaprolactone (PCL)-based films integrated with hairy cellulose nanocrystals and silver nanoparticles for active Tilapia packaging applications

The migration of metal ions to the food matrix has been always a challenge in the production of active food packaging films. In this study, it was tried to evaluate the idea of using hairy cellulose nanocrystals (HCNs) in controlling the migration of Silver Nanoparticles (AgNPs) from polycaprolactone (PCL)-based films to the Tilapia fish. HCNs and the final films (integrated with various amounts of HCNs and AgNPs) were evaluated physicochemically and mechanically. Tilapia fish were packed using the films and after specific periods, the fish samples were assessed microbiologically and physiochemically. According to the results, incorporating NPs into PCL films enhanced tensile strength, elasticity, and toughness making the films more resistant to breakage and deformation under stress. The introduction of HCNs reduced the surface roughness level, decreasing AgNPs migration, but also accelerated the degradation rate. Films with [1% AgNPs +2% HCNs] and [1% AgNPs] had the lowest and highest water vapor transmission rate. The use of AgNPs (1%) + HCNs (2%) incorporated into PCL films resulted in a lower pH value, TVB-N, TBARs, and PV. It also decreased microbial activities in samples in comparison to the control. Therefore, the idea of using HCNs along with antibacterial metal-based nanoparticles can control the rate of ion migration.

Biosynthesis, characterization and antimicrobial activities of zinc oxide nanoparticles from leaf and seed extracts of Malva neglecta Wallr

Recent years have witnessed a growing embrace of green chemistry for nanoparticle manufacturing due to its time and energy efficiency compared to conventional methods. This research aimed to biosynthesize zinc oxide nanoparticles (ZnO NPs) using environmentally friendly aqueous extracts from Malva neglecta leaves and seeds as reducing and stabilizing agents. Various analytical methods, including UV–Vis spectrophotometry, FTIR, XRD, TGA, EDX, and TEM, confirmed the synthesis and characterization of ZnO NPs. Their antioxidant activity was assessed using the DPPH assay, while antibacterial properties were examined against S. aureus and E. coli, along with determining minimum inhibitory concentration (MIC) and minimum bactericidal concentration (MBC) values. FTIR spectra indicated ZnO bonding and surfactant molecule adsorption on ZnO NPs’ surface. TEM revealed spherical and hexagonal ZnO NPs with an average size of 40–50 nm. This green synthesis method with Malva neglecta extracts is eco-friendly, cost-effective, and safe, producing antibacterial nanoparticles without adverse effects.

Discovery of antibacterial biogenic magnetosome nanoparticles from Providencia sp. MTBPRB-1: Screening, purification and characterization

Discovery of antibacterial biogenic magnetosome nanoparticles from Providencia sp. MTBPRB-1: Screening, purification and characterization

Surface Topography Steer Soft Tissue Response and Antibacterial Function at the Transmucosal Region of Titanium Implant.

Metallic dental implants have been extensively used in clinical practice due to their superior mechanical properties, biocompatibility, and aesthetic outcomes. However, their integration with the surrounding soft tissue at the mucosal region remains challenging and can cause implant failure due to the peri-implant immune microenvironment. The soft tissue integration of dental implants can be ameliorated through different surface modifications. This review discussed and summarized the current knowledge of topography-mediated immune response and topography-mediated antibacterial activity in Ti dental implants which enhance soft tissue integration and their clinical performance. For example, nanopillar-like topographies such as spinules, and spikes showed effective antibacterial activity in human salivary biofilm which was due to the lethal stretching of bacterial membrane between the nanopillars. The key findings of this review were (I) cross-talk between surface nanotopography and soft tissue integration in which the surface nanotopography can guide the perpendicular orientation of collagen fibers into connective tissue which leads to the stability of soft tissue, (II) nanotubular array could shift the macrophage phenotype from pro-inflammatory (M1) to anti-inflammatory (M2) and manipulate the balance of osteogenesis/osteoclasia, and (III) surface nanotopography can provide specific sites for the loading of antibacterial agents and metallic nanoparticles of clinical interest functionalizing the implant surface. Silver-containing nanotubular topography significantly decreased the formation of fibrous encapsulation in per-implant soft tissue and showed synergistic antifungal and antibacterial properties. Although the Ti implants with surface nanotopography have shown promising in targeting soft tissue healing in vitro and in vivo through their immunomodulatory and antibacterial properties, however, long-term in vivo studies need to be conducted particularly in osteoporotic, and diabetic patients to ensure their desired performance with immunomodulatory and antibacterial properties. The optimization of product development is another challenging issue for its clinical translation, as the dental implant with surface nanotopography must endure implantation and operation inside the dental microenvironment. Finally, the sustainable release of metallic nanoparticles could be challenging to reduce cytotoxicity while augmenting the therapeutic effects.

Synthesis, characterization, and investigation of antibacterial activity of Novel CMC/CuO NPs/CQDs bionanocomposite coating

In recent decades, healthcare-associated infections (HAIs) have become a common problem in healthcare facilities such as hospitals. As a result, researchers are currently developing nanocomposite coatings that are strengthened with antibacterial nanoparticles. In this research, a novel antibacterial bionanocomposite coating based on carboxymethyl cellulose polymer/copper oxide nanoparticles/carbon quantum dots was coated on medical grade 316 stainless steel by sol-gel dip-coating method. The effect of the concentration of nanocomposite components was investigated at four different levels to determine the best ratio with the most antibacterial activity. Structural characteristics of nanocomposite and coating were investigated using different analysis methods. The coating analysis showed that reinforcements are uniformly distributed in the polymer matrix. Antibacterial test of disc diffusion was performed by the Kirby-Bauer method and minimum inhibitory concentration (MIC) and minimum bactericidal concentration (MBC) antibacterial test. The results showed that bionanocomposite was effective in the MIC assays against Staphylococcus aureus and Escherichia coli with MIC values of 25 mg/ml and >50 mg/ml, respectively. The inhibition zones for E. coli and S. aureus were 17 and 32 mm, respectively, at 10 μg/disc of gentamicin. SEM images displayed significant and evident alterations in the structure of bacterial morphology, indicating cellular damage.

Chitosan-based hydrogel incorporating mesoporous silica/zinc oxide nanoparticles with controlled swelling and potent antibacterial activity

Staphylococcus aureus (S. aureus) is a notable causative agent of bacterial infections known for its development of antibiotic resistance over time. In response, hydrogels augmented with antibacterial nanoparticles (NPs) and controllable swelling properties have emerged as promising alternatives. In the study, a novel chitosan (CS)-based hydrogel was prepared by combining CS as a main component, zinc oxide NPs (ZnO NPs) as an antibacterial agent, and mesoporous silica NPs (MSN) as the swelling control material. Comprehensive characterization of the prepared novel hydrogels were carried out by dynamic light scattering (DLS), zeta potential (ζ-potential), Brunauer–Emmett–Teller (BET) analysis, Fourier-transform infrared spectroscopy (FTIR), scanning electron microcopy (SEM), and X-ray diffraction (XRD). The ZnO/MSN/CS-based hydrogel exhibited superior swelling, precisely controllable swelling, and potent antibacterial activity against S. aureus. These hybrid CS-based hydrogels, incorporating both ZnO NPs and MSN, exhibit significant potential as agents for combating antibiotic resistance, offering an alternative strategy to mitigate reliance on conventional antibiotics.

In Vitro Antibacterial and Anti-Inflammatory Properties of Imidazolium Poly(ionic liquids) Microspheres Loaded in GelMA-PEG Hydrogels.

Repairing damaged tissue caused by bacterial infection poses a significant challenge. Traditional antibacterial hydrogels typically incorporate various components such as metal antimicrobials, inorganic antimicrobials, organic antimicrobials, and more. However, drawbacks such as the emergence of multi-drug resistance to antibiotics, the low antibacterial efficacy of natural agents, and the potential cytotoxicity associated with metal antibacterial nanoparticles in hydrogels hindered their broader clinical application. In this study, we successfully developed imidazolium poly(ionic liquids) (PILs) polymer microspheres (APMs) through emulsion polymerization. These APMs exhibited notable antibacterial effectiveness and demonstrated minimal cell toxicity. Subsequently, we integrated the APMs into a gelatin methacryloyl (GelMA)-polyethylene glycol (PEG) hydrogel. This composite hydrogel not only showcased strong antibacterial and anti-inflammatory properties but also facilitated the migration of human skin fibroblasts (HSF) and human umbilical vein endothelial cells (HUVECs) and promoted osteogenic differentiation in vitro.

Biomimetic spray coating for fruit preservation based on UiO-1 67 metal–organic framework nanozyme

The application of edible coatings for preparing composite antibacterial spray coatings for fruit preservation by incorporating antibacterial nanoparticles has gained increasing attention. Chitosan (CS) is a natural polysaccharide used as an edible coating to preserve fruit; it has properties such as reducing water loss, enhancing appearance, and improving mechanical properties. By combining it with antibacterial material, it can reduce fruit microorganisms. Cerium (Ce) has excellent antibacterial activity combined with the advantages of safety and low cost. Therefore, this study proposes a biocatalytic spray coating for fruit preservation using a CS composite metal–organic framework (CS@Ce-MOF) with strawberry as a model fruit. CS@Ce-MOFs are superior to Ce-MOFs in the aqueous stability of their chemical structure, inoxidizability, antibacterial duration, and validity. The well-characterized CS@Ce-MOF was verified to simultaneously mimic good oxidase- and apyrase-like activities. CS@Ce-MOF biocatalytic spray coating demonstrated excellent antibacterial properties against two common foodborne pathogens: Escherichia coli and the Gram-positive bacterium Staphylococcus aureus, with high killing rates of up to 94.5%. This is due to the unique structure of the CS@Ce-MOF composite, which presents a large surface area for contact with pathogens and enhances the catalytic activity of the incorporated cerium oxide nanoparticles, leading to efficient sterilization. Furthermore, the scavenging rate of DPPH and ABTS free radicals is more than 80%, indicating that CS@Ce-MOF has excellent antioxidant properties. Moreover, CS@Ce-MOF minimized the weight loss and firmness of strawberries and bananas over 7 days of ambient storage. The use of such a biocatalytic spray coating has enormous potential for preserving the quality and safety of fresh produce, reducing food waste, and promoting sustainable agricultural practices.

ZnO and Fe2TiO5 nanoparticles obtained by green synthesis as active components of alginate food packaging films

The aim of this study was to develop an active alginate packaging film incorporating antioxidant Fe2TiO5 and antibacterial ZnO nanoparticles, obtained by green synthesis utilizing citrus peel waste. The average particle size was estimated as 10 nm for ZnO and 50 nm for Fe2TiO5. Films were prepared using 2.33% (w/v) sodium alginate with 0.11% (w/v) Fe2TiO5 and/or ZnO nanoparticles. The inclusion of nanoparticles resulted in a noticeable colour difference, reduced the transparency, increased UV light protection and improved thermal stability of the film. The dry matter content of the films was around 83%. Film solubility in distilled water was low (< 8%) mainly reflecting crosslinking of the alginate polymer and Ca2+-ions. The lowest swelling degree was obtained for the ZnO/Fe2TiO5 –alginate film (178%). The efficiency of these packaging films was demonstrated through preservation of strawberry freshness. Alginate packaging film with a mixture of metal oxide nanoparticles can facilitate food safety and increase food shelf life.

Enhancing bone tissue engineering using iron nanoparticles and magnetic fields: A focus on cytomechanics and angiogenesis in the chicken egg chorioallantoic membrane model.

To evaluate the potential of iron nanoparticles (FeNPs) in conjunction with magnetic fields (MFs) to enhance osteoblast cytomechanics, promote cell homing, bone development activity, and antibacterial capabilities, and to assess their in vivo angiogenic viability using the chicken egg chorioallantoic membrane (CAM) model. Experimental study conducted in a laboratory setting to investigate the effects of FeNPs and MFs on osteoblast cells and angiogenesis using a custom titanium (Ti) substrate coated with FeNPs. A custom titanium (Ti) was coated with FeNPs. Evaluations were conducted to analyze the antibacterial properties, cell adhesion, durability, physical characteristics, and nanoparticle absorption associated with FeNPs. Cell physical characteristics were assessed using protein markers, and microscopy, CAM model, was used to quantify blood vessel formation and morphology to assess the FeNP-coated Ti's angiogenic potential. This in vivo study provided critical insights into tissue response and regenerative properties for biomedical applications. Statistical analysis was performed using appropriate tests to compare experimental groups and controls. Significance was determined at P < 0.05. FeNPs and MFs notably improved osteoblast cell mechanical properties facilitated the growth and formation of new blood vessels and bone tissue and promoted cell migration to targeted sites. In the group treated with FeNPs and exposed to MFs, there was a significant increase in vessel percentage area (76.03%) compared to control groups (58.11%), along with enhanced mineralization and robust antibacterial effects (P < 0.05). The study highlights the promising potential of FeNPs in fostering the growth of new blood vessels, promoting the formation of bone tissue, and facilitating targeted cell migration. These findings underscore the importance of further investigating the mechanical traits of FeNPs, as they could significantly advance the development of effective bone tissue engineering techniques, ultimately enhancing clinical outcomes in the field.

Preparation of a coating solution for antibacterial Ag nanoparticle layers

Preparation of a coating solution for antibacterial Ag nanoparticle layers

Coated Cotton Fabrics with Antibacterial and Anti-Inflammatory Silica Nanoparticles for Improving Wound Healing.

Herein, we report the preparation of bifunctional silica nanoparticles by covalent attachment of both an anti-inflammatory drug (ibuprofen) and an antibiotic (levofloxacin or norfloxacin) through amide groups. We also describe the coating of cotton fabrics with silica nanoparticles containing both ibuprofen and norfloxacin moieties linked by amide groups by using a one-step coating procedure under ultrasonic conditions. The functionalized nanoparticles and cotton fabrics have been characterized using spectroscopic and microscopic techniques. The functionalized nanoparticles and textiles have been treated with model proteases for the in situ release of the drugs by the amide bond enzymatic cleavage. Topical dermal applications in medical bandages are expected, which favor wound healing.

Biosynthesis of high antibacterial silver chloride nanoparticles against Ralstonia solanacearum using spent mushroom substrate extract

Abstract In this study, a green and highly efficient method was proposed to synthesize nano-silver chloride (nano-AgCl) by using spent mushroom substrate (SMS) extract as a cheap reactant. Nanoparticles were characterized by a series of techniques like X-ray diffraction (XRD), energy dispersive spectroscopy (EDS), scanning electron microscopy (SEM), and transmission electron microscopy (TEM), which showed the formation of near-spherical silver chloride nanoparticles with an average size of about 8.30 nm. Notably, the synthesized nano-silver chloride has a more prominent antibacterial effect against Ralstonia solanacearum (EC50=5.18 mg/L) than non-nano-sized silver chloride particles, nano-silver chloride synthesized by chemical method, and commercial pesticides. In-depth, the study of mechanism revealed that nano-silver chloride could cause cell membrane disruption, DNA damage and intracellular generation of reactive oxygen species (•OH, •O2- and 1O2) leading to peroxidation damage in Ralstonia solanacearum (R. solanacearum). And the reaction between nano-silver chloride and bacteria could be driven by intermolecular forces instead of electrostatic interactions. Our study provides a new approach to synthesizing nano-silver chloride as a highly efficient antibacterial agent and broadens the utilization of agricultural waste spent mushroom substrate.

Mechanism of Action and Design of Potent Antibacterial Block Copolymer Nanoparticles.

Self-assembled polymer nanoparticles are promising antibacterials, with nonspherical morphologies of particular interest as recent work has demonstrated enhanced antibacterial activity relative to their spherical counterparts. However, the reasons for this enhancement are currently unclear. We have performed a multifaceted analysis of the antibacterial mechanism of action of 1D nanofibers relative to nanospheres by the use of flow cytometry, high-resolution microscopy, and evaluations of the antibacterial activity of pristine and tetracycline-loaded nanoparticles. Low-length dispersity, fluorescent diblock copolymer nanofibers with a crystalline poly(fluorenetrimethylenecarbonate) (PFTMC) core (length = 104 and 472 nm, height = 7 nm, width = 10-13 nm) and a partially protonated poly(dimethylaminoethyl methacrylate) (PDMAEMA) corona (length = 12 nm) were prepared via seeded growth living crystallization-driven self-assembly. Their behavior was compared to that of analogous nanospheres containing an amorphous PFTMC core (diameter of 12 nm). While all nanoparticles were uptaken into Escherichia coli W3110, crystalline-core nanofibers were observed to cause significant bacterial damage. Drug loading studies indicated that while all nanoparticle antibacterial activity was enhanced in combination with tetracycline, the enhancement was especially prominent when small nanoparticles (ca. 15-25 nm) were employed. Therefore, the identified differences in the mechanism of action and the demonstrated consequences for nanoparticle size and morphology control may be exploited for the future design of potent antibacterial agents for overcoming antibacterial resistance. This study also reinforces the requirement of morphological control over polymer nanoparticles for biomedical applications, as differences in activity are observed depending on their size, shape, and core-crystallinity.