Antibacterial Silver Nanoparticles Research Articles

Phyto-assisted synthesis of Silver nanoparticles using Tinospora cordifolia leaf extract and their antibacterial activity: An ecofriendly approach

To meet the increasing demands for commercial nanoparticles new eco-friendly methods of synthesis are being discovered. Plant mediated synthesis of nanoparticles offers single step, easy extracellular synthesis of nanoparticles. We report the synthesis of antibacterial Silver nanoparticles using leaf extract of the medicinal plant, Tinospora cordifolia. The leaf extract was prepared by boiling chopped leaves of Tinospora cordifolia in deionized water for 10 min and filtering the mixture with Whatman filter paper No.1. The filtrate was used as a reducing agent and stabilising agent for AgNO3. On adding 1 mM solution of Silver nitrate to the leaf extract and stirring at 75 °C for 25 min, a change in colour from yellow-brown to brown-black specified the production of Silver nanoparticles. The formation of Silver nanoparticles was monitored by UV-visible spectroscopy and further characterization of the synthesized Silver nanoparticles was done by XRD studies. The antibacterial studies were performed on Gram negative and Gram positive pathogens, Salmonella typhi, Pseudomonas aeruginosa, Enterobacter aerogenes and Staphylococcus aureus, by agar well diffusion method, on Mueller Hinton agar medium. The Silver nanoparticles synthesized from Tinospora cordifolia leaf extract were found to have antimicrobial activity against these Gram negative and Gram positive pathogenic bacteria.

Phytochemical Screening and Green Synthesis of Antibacterial Silver Nanoparticles of Sapindus mukorossi Fruit Extracts

Background: Plants, herbs, and ethnobotanicals have been utilized for health promotion and disease treatment since the dawn of time and are still widely employed today. The immense demand and potential health advantages of herbal medicines balance out the enormous research demands. There is a need for research on the quality, safety, molecular effects, and therapeutic efficacy of the many common herbs. Aim and Objective: The aim of the study is to prepare Silver Nanoparticles using fruit extract of Sapindus Mukorossi by green synthesis technique, and to develop new derivatives of antibiotic due to high resistance from conventional antibiotics. Method: The Sapindus mukorossi fruit extract AgNPs was prepared by green synthesis technique. Formulation of silver nanoparticles using water/methanol reetha fruit extract was carried out by addition of fruit extract to a reaction mixture containing 1M AgNO3 and 0.625% ammonia solution and left for 48hrs in dark place with regular interval exposing to light. The prepared silver nanoparticles were characterized using SEM, FTIR and XRD studies. Result: The synthesized nanoparticles found to be spherical and crystalline in nature. The FTIR measurements identifies the functional groups attributed for silver ions reduction and AgNPs stabilization. The synthesized yield was 58.34%, 77.46%, 49.67% and 69.32% respectively. The methanol extract shows greater activity than Aqueous extract against E.coli and Streptococcus aureus. Conclusion: The Phyto-based drugs exhibit good medicinal properties with less side-effects as compare to synthetic based drugs. The reetha is known for its many properties such as foaming agent, antibacterial activity etc. The idea was to develop the new antibacterial drugs as the humans getting resistant to the antibacterial drugs. The antibacterial results show that the prepared AgNPs were effective in inhibiting growth of both S. aureus and E. coli bacteria, and hence they could be potential applications in bio-related field.

Rosella Petal Extract (Hibiscus sabdariffa Linn.) as a Reducing Agent in Silver Nanoparticle Synthesis and Its Antibacterial Activity

Silver nanoparticles have superior properties that attract much attention because they can increase their effectiveness and efficiency compared to their macroscopic size. Silver nanoparticles have several benefits, one of which is as an antibacterial agent. Synthesis of silver nanoparticles was carried out by reducing silver ions (Ag+) to uncharged silver (Ag0) using a reducing agent from Hibiscus sabdariffa Linn. petal extract. This research aims to synthesize silver nanoparticles by studying several parameters that influence their formation, such as the pH of Hibiscus sabdariffa Linn. petal extract, reaction time, silver nitrate concentration, and Hibiscus sabdariffa Linn. petal extract concentration. The silver nanoparticles formed were then tested for their antibacterial activity. The experimental results showed that the best synthesis was performed using Hibiscus sabdariffa Linn. petal extract with pH 10, reaction time of 45 minutes, silver nitrate concentration of 1×10-4 M, and Hibiscus sabdariffa Linn. petal extract concentration of 0.004%. The synthesized silver nanoparticles, examined through a transmission electron microscope, exhibited a size distribution ranging from 2 to 26 nm with an average size of 12 ± 3 nm, which was stable with a storage time of 3 months. Silver nanoparticles showed antibacterial activity against Staphylococcus aureus. Hibiscus sabdariffa Linn. petal extract is a promising reducing agent for producing antibacterial silver nanoparticles, showcasing its potential in this application.

Multi-spectroscopic and thermodynamic profiles on HSA binding of Cassia fistula leaf based potential antibacterial and anticancer silver nanoparticles

Here, a simple, one step, lucrative and green synthesis of Cassia fistula leaf extract inspired antibacterial silver nanoparticles (CF-SNPs) was provided. Characterization of these CF-SNPs were achieved by using various spectroscopic techniques for instance Ultraviolet Visible (UV-Vis) Spectroscopy, Fourier-Transform Infrared (FTIR) Spectroscopy, Dynamic Light Scattering (DLS), Transmission Electron Microscopy (TEM) and Energy Dispersive X-ray (EDX). The effective antibacterial action of the CF-SNPs was checked against Escherichia coli (E. Coli) DH5-Alpha where MIC was 1.6 nM. Anticancer dynamism of the CF-SNPs was also tested in opposition to skin melanoma, A375 cell lines in which 4.4 nM was IC50. The binding proneness of HSA towards CF-SNPs was investigated by means of UV-Vis Spectroscopy, Fluorescence Spectroscopy, Time Resolved Fluorescence Spectroscopy, Circular Dichroism (CD) Spectroscopy, Dynamic Light Scattering, and Isothermal Titration Colorimetry (ITC). CD spectroscopy established minor secondary structural exchange of HSA in HSA-CF-SNPs complex. ITC and Time Resolved Fluorescence Spectroscopy verified the static type quenching mechanism involved in HSA-CF-SNPs complex. The binding constant was 3.45 × 108 M−1 at 298.15K from ITC study. The thermodynamic parameters showed that the interaction was occurred spontaneously by the hydrophilic forces and hydrogen bonding. Communicated by Ramaswamy H. Sarma

Exploring the antibacterial potential of magnetite/Quince seed mucilage/Ag nanocomposite: Synthesis, characterization, and activity assessment

In this study, we present a novel core-shell antibacterial agent designed for water disinfection purposes. The nanocomposite is synthesized by combining quince seed mucilage (QSM) as the shell material and Fe3O4 as the core material. The integration of antibacterial silver nanoparticles (Ag NPs) onto the QSM shell effectively prevents agglomeration of the Ag NPs, resulting in a larger contact surface area with bacteria and consequently exhibiting enhanced antibacterial activity. The incorporation of magnetic Fe3O4 NPs with a saturation magnetization of 55.2 emu·g−1 as the core allows for easy retrieval of the nanocomposites from the medium using a strong magnetic field, enabling their reusability. The Fe3O4/QSM/Ag nanocomposite is extensively characterized using XRD, FT-IR, VSM, DLS, FE-SEM, and TEM techniques. The characterization results confirm the successful synthesis of the nanocomposites, with an average particle size of 73 nm and no contamination or impurities detected. The nanocomposites exhibit superparamagnetic properties, with a saturated magnetization of 22.69 emu·g−1, ensuring facile separation from water. The antibacterial activity of the synthesized nanocomposite is evaluated using the disk diffusion method against both Gram-positive and Gram-negative bacteria. The results reveal excellent antibacterial efficacy, with minimum inhibition concentrations (MIC) of 0.8 mg·mL−1 against E. coli and S. typhimurium. Furthermore, the measurement of released silver ions in water using ICP-OES indicates a low concentration of remaining silver ions in the medium, highlighting the controlled release of antimicrobial agents. Overall, this study provides valuable insights into the development of advanced antibacterial agents for water disinfection applications, offering potential solutions to combat microbial contamination effectively.

Antibacterial AgNPs-PAAm-CS-PVP nanocomposite hydrogel coating for urinary catheters

Catheter-associated urinary tract infections (CAUTI) account for 40% of all hospital-acquired infections and more than 1 million CAUTIs occur annually in the United States and Europe with increased morbidity and mortality. Although anti-bacterial coating is an effective way to solve this problem, so far only limitted progress has been made. In this paper we prepared a novel antibacterial silver nanoparticles poly(acrylamide)-chitosan-polyvinylpyrrolidone (AgNPs-PAAm-CS-PVP) composite hydrogel coating on latex urinary catheters by a simple dipping method. The average particle size, the size distribution as well as the polydispersity index (PDI) value of the AgNPs were examined by using TEM analysis. The surface morphology and roughness, the element contents, the functional groups, the static contact angles, and the surface energy of the coatings were characterized by using SEM, EDS, AFM, FTIR, XPS, and a video optical contact angle instrument, respectively. The amount of the total Ag released from the hydrogel was tested by ICP-MS. The antibacterial and antiadhesion efficacies against Gram-negative E. coli of the coated urinary catheters were evaluated with an inhibition zone test and fluorescence microscopy. A synergistic antibacterial mechanism of AgNPs and CS was also presented. The results showed that the synthesized AgNPs in the hydrogel had a spherical shape with an average diameter of 25.9 nm. The AgNPs-PAAm-CS-PVP hydrogel had a more durable release of the antibacterial agents of AgNPs and Ag+, which explains why the coated urinary catheters had long-term antibacterial activity. The mathematical modelling of Ag release kinetics supported Case I or Fickian diffusion mechanism for the AgNPs-PAAm-CS-PVP hydrogel. The hydrogel-coated urinary catheters became smoother and more hydrophilic which further explains why the coated urinary catheter decreased bacterial adhesion. More importantly, bacterial activity and bacterial adhesion assays showed that both the outer and inner surfaces of the AgNPs-PAAm-CS-PVP hydrogel-coated urinary catheters had strong antibacterial property against E. coli. Furthermore, the hydrogel-coated urinary catheters showed high hemocompatibility and cytocompatibility for promising biomedical applications. The AgNPs-PAAm-CS-PVP hydrogel-coated urinary catheters have great potential for decreasing CAUTIs.

Development and Experimental Evaluation of Some Silver Nanoparticles with Antimicrobial Potential

By adjusting the synthesis process, silver nanoparticles (AgNp) of various shapes, sizes, and structures can be obtained, all of which have a substantial impact on the biological effect, notably, the regulation of antibacterial activity in the present circumstances of growing bacterial resistance. Due to their relatively small size, nanoparticles may be disseminated evenly throughout the body of the experimental animal, even at low doses, and exert more potent antibacterial activities. Our research was centered on the synthesis, production, and biological evaluation of antibacterial silver nanoparticles. Using the Turkevich method, we were able to effectively synthesize and characterize nanoscale silver particles, with an average crystallite size of 9.49 nm. We examined their acute toxicity and pharmacokinetic characteristics in rats after administering a single dosage. In addition, we evaluated the biological effect of topical AgNp suspension on the progression of burn-type lesions in the experimental animals. The pharmacokinetic profile demonstrated that the plasma concentration of silver nanoparticles, as well as their clearance rate, and dispersion throughout the body, are significantly enhanced in large rodent species. The restorative effect of synthesized silver nanoparticles in the form of a suspension in distilled water was corroborated by the values of the hematological parameters. These results demonstrated an intense stimulation of the cellular and molecular processes of the local immune defense, which has resulted in significantly faster regeneration in the AgNp-treated group.

Mussel Inspired In Situ Preparation of Antibacterial Silver Nanoparticles by DOPA-Containing Silk Fibroin.

Silver nanoparticles (AgNPs) attract a great deal of attention for potent antibacterial capacity, but their use is challenged by limited stability. Inspired by the adhesive and redox properties of the mussel foot proteins containing L-3,4-dihydroxyphenylalanine (DOPA), a facile strategy for in situ synthesis of AgNPs using DOPA-containing fibroin is developed. Tyrosine residues in fibroin are transformed into DOPA via biomimetic synthesis method with content of 0.55mol%. In situ synthesis generates stable and small AgNPs through DOPA bound in fibroin as a reducing and stabilizing agent. Narrow size distribution with average diameter of 20nm and excellent monodispersity are obtained. Cross-linking with lysine increases the content of β-sheet to form hydrogel and achieves gradual release of silver. The material exhibits excellent antibacterial properties against Gram-positive Staphylococcus aureus and Gram-negative Escherichia coli bacteria. It can be potentially applied in biological and medical fields to treat bacterial infections.

Antibacterial silver nanoparticles: effects on bacterial nucleic acids

Various microorganisms are located on the human skin, mucous membrane and inside the human body. Many of these microorganisms are beneficial and few are even essential, however, some pathogens are known to cause infection and have the ability to attack and damage the host tissue. Treatment of infectious bacterial disease by antibiotics is one of the major conventional strategies. Gram-positive and Gram-negative bacteria have developed resistance to conventional antibiotics by various mechanisms, including overexpression of efflux pumps, preventing drug penetration into the cells, genetic mutations, increased production of competitive inhibitors of antibiotics, or overexpression of enzymes that inactivate or hydrolyze antibiotics. Consequently, finding a new approach to overcome these hindrances is vital for the treatment of severe bacterial infections. Nanomaterials can be effective therapeutic compounds, with unique properties compared to bulk materials. Metal and metal oxide nanoparticles, particularly silver nanoparticles, have demonstrated strong antibacterial activity against most (if not all) multidrug-resistant bacteria. Several antibacterial mechanisms have been proposed for these nanoparticles, however, their interaction with bacterial nucleic acids is not completely understood, so this review discusses recent advances in this area.

Biological activity of synthesized silver nanoparticles on S. aureus and P. aeruginosa

Silver nanoparticles (AgNPs) that were biologically synthesized using Moringa oleifera leave extract showed good antibacterial activity against two tested bacterial strains namely: Pseudomonas aeruginosa as a model for Gram- negative bacteria and Staphylococcus aureus as a model for Gram- positive bacteria. Minimum inhibitory concentration (MIC) of antibacterial silver nanoparticles that were biologically synthesized using Moringa oleifera leave extract was tested to estimate the effect of nanoparticles on cell viability, cell integrity, and cell permeability of tested bacteria. The results indicated that there was a great effect of AgNPs on cell viability of bacterial strains tested as there was significance in growth kinetics between control and treated bacteria with silver nanoparticles. Also, cell permeability of S. aureus and P. aeruginosa were greatly affected by biologically synthesized silver nanoparticles and statistical analysis revealed that there was significant difference in cell permeability of two tested bacteria between control and treated cells with nanoparticles. However, there were slightly effect of these nanoparticles on cell integrity when the absorbance of DNA was estimated.

A spatiotemporal drug release scaffold with antibiosis and bone regeneration for osteomyelitis

IntroductionScaffolds loaded with antibacterial agents and osteogenic drugs are considered essential tools for repairing bone defects caused by osteomyelitis. However, the simultaneous release of two drugs leads to premature osteogenesis and subsequent sequestrum formation in the pathological situation of unthorough antibiosis. ObjectivesIn this study, a spatiotemporal drug-release polydopamine-functionalized mesoporous silicon nanoparticle (MSN) core/shell drug delivery system loaded with antibacterial silver (Ag) nanoparticles and osteogenic dexamethasone (Dex) was constructed and introduced into a poly-l-lactic acid (PLLA) scaffold for osteomyelitis therapy. MethodsMSNs formed the inner core and were loaded with Dex through electrostatic adsorption (MSNs@Dex), and then polydopamine was used to seal the core through the self-assembly of dopamine as the outer shell (pMSNs@Dex). Ag nanoparticles were embedded in the polydopamine shell via an in situ growth technique. Finally, the Ag-pMSNs@Dex nanoparticles were introduced into PLLA scaffolds (Ag-pMSNs@Dex/PLLA) constructed by selective laser sintering (SLS). ResultsThe Ag-pMSNs@Dex/PLLA scaffold released Ag+ at the 12th hour, followed by the release of Dex starting on the fifth day. The experiments verified that the scaffold had excellent antibacterial performance against Escherichia coli and Staphylococcus aureus. Moreover, the scaffold significantly enhanced the osteogenic differentiation of mouse bone marrow mesenchymal stem cells. ConclusionThe findings suggested that this spatiotemporal drug release scaffold had promising potential for osteomyelitis therapy.

A Review of Children’s Prosthetic Self-hygiene Using Antibacterial Silver Nanoparticles (AgNPs)

Sports prostheses represent a critical facet in enhancing the mobility and quality of life for children with limb loss. However, prolonged usage of these prosthetic devices introduces substantial challenges related to hygiene and the heightened risk of infection. This comprehensive review endeavors to delve into the untapped potential of utilizing antibacterial silver nanoparticles (AgNPs) to foster self-hygiene practices in pediatric sports prostheses. AgNPs have emerged as a compelling area of research, largely attributable to their formidable antibacterial properties, offering revolutionary prospects in the realm of antibacterial therapy. Central to this exploration is an in-depth analysis of their antibacterial activity, elucidating their intricate mechanisms of action against bacterial agents. The unique physicochemical attributes, characterized by their diminutive size and expansive surface area, synergize to elevate their antibacterial efficacy significantly. The antibacterial mechanisms involve the controlled release of silver ions, which disrupt bacterial cell membranes, impede vital cellular processes, and provoke oxidative stress within the pathogens. Moreover, they exhibit the propensity for synergistic interactions when employed in tandem with conventional antibiotics, thereby positioning themselves as promising candidates for combination therapy. This review further encompasses a comprehensive survey of diverse methodologies employed for the synthesis of AgNPs and their multifarious application in various domains, including the realm of prosthetics and medicine. Nevertheless, as with any emerging technology, the implementation of AgNPs does not come without its challenges. Issues pertinent to the stability of AgNPs, potential toxicity concerns, and the development of bacterial resistance necessitate critical consideration for their successful integration into pediatric sports prostheses. In summation, AgNPs epitomize a compelling arsenal of antibacterial agents, propelling the possibilities of innovative therapeutic strategies in the battle against bacterial infections. This review underscores their remarkable potential while underscoring the imperative need for further research and development to unlock their full efficacy in the context of pediatric sports prostheses and beyond.

Dual mode antibacterial surfaces based on Prussian blue and silver nanoparticles.

Prussian Blue (PB) is an inexpensive, biocompatible, photothermally active material. In this paper, self-assembled monolayers of PB nanoparticles were grafted on a glass surface, protected with a thin layer of silica and decorated with spherical silver nanoparticles. This combination of a photothermally active nanomaterial, PB, and an intrinsically antibacterial one, silver, leads to a versatile coating that can be used for medical devices and implants. The intrinsic antibacterial action of nanosilver, always active over time, can be enhanced on demand by switching on the photothermal effect of PB using near infrared (NIR) radiation, which has a good penetration depth through tissues and low side effects. Glass surfaces functionalized by this layer-by-layer approach have been characterized for their morphology and composition, and their intrinsic and photothermal antibacterial effect was studied against Gram+ and Gram- planktonic bacteria.

Efficacy of Sterculia diversifolia Leaf Extracts: Volatile Compounds, Antioxidant and Anti-Inflammatory Activity, and Green Synthesis of Potential Antibacterial Silver Nanoparticles.

Sterculia diversifolia, widely distributed in Jordan as an ornamental plant, is a synonoum for Brachychiton populneus. Phytochemical studies examining the volatile chemicals in Sterculia diversifolia leaves are limited, despite the rising demand for their numerous applications. Furthermore, it was only recently that a report described the friendly synthesis of silver nanoparticles (AgNPs) using aqueous extract derived from Brachychiton populneus leaves. Therefore, AgNPs were produced using either aqueous plant extracts (AgWPE) or ethanolic plant extracts (AgEPE), and Shimadzu GC-MS equipment was used to detect volatile compounds in the ethanolic leaf extracts. GC-MS profile of leaf ethanolic extracts of the Jordanian chemotypes of S. diversifolia revealed the existence of major components: (3β)-Lup-20(29)-en-3-ol acetate (30.97%) and 1-octadecyne (24.88). Other compounds are squalene (7.19%), germanicol (6.23), dl-α-tocopherol (5.24), heptacosane (4.41), phytol (3.54) and pentacosane (2.89). According to published studies, these reported chemicals have numerous uses, including as animal feed, vitamin precursors, possible eco-friendly herbicides, antioxidants, and anti-inflammatory agents. Aqueous extracts of S. diversifolia leaves had total phenolic of 5.33 mg GAE/g extract and flavonoid contents of 64.88 mg QE/g extract, respectively. The results indicated the contribution of phenolic and flavonoids to this plant’s anti-inflammatory and antioxidant properties. The reduction in AgNO3 to AgNPs using S. diversifolia leaf extracts was confirmed by the change in solution color from colorless to dark black. Further characterization was attempted by X-ray diffraction, Malvern zeta-sizer and scanning electron microscope. The efficacy of synthesized Ag nanoparticles using aqueous or ethanolic plant extract of S. diversifolia against the Gram-negative bacteria Escherichia coli and Gram-positive bacteria Staphylococcus aureus showed appreciable activity at 25 µg/mL concentration compared to the source plant extracts.

Characterization of Green Synthesized Antibacterial Silver Nanoparticles from Amaranthus spinosus L. Extract

Characterization of Green Synthesized Antibacterial Silver Nanoparticles from Amaranthus spinosus L. Extract

Acoustoplasma synthesis of silver nanoparticles with antibacterial properties

In this work, antibacterial silver nanoparticles were synthesized under the combined effect of high-intensity ultrasonic vibrations on a liquid medium above the cavitation threshold and pulsed or stationary electric fields. These conditions lead to the specific form of plasma discharge in a cavitating liquid medium. This type of discharge is a new, earlier poorly studied physical phenomenon with original electrophysical and optical characteristics. Silver rods were used as materials for the discharge electrodes.

Green Synthesis of Antibacterial Silver Nanoparticles against Drug Resistant Bacteria

Background: Nanotechnology brings a massive revolution in the domain of medical biotechnology. Plants possess thousands of antimicrobial compounds; these compounds can be extracted and utilized in the production of medicines. Objective: The aim of this research is to design an economical method for the formation of nanoparticles from plants and explore their antibacterial activity. Methods: In the present study, we used the plants Aloe barbadensis, Azadirachta indica, Carica papaya, Mentha arvensis and Catharanthus roseus. Ethanolic, methanolic and aqueous extracts of the above mentioned plants were used to prepare silver nanoparticles. Antimicrobial activities of the nanoparticles of extracts were determined against pathogenic strains of bacteria. Results: Results showed that silver nanoparticles are formed from the ethanolic and methanolic extracts of Azadirachta indica, Carica papaya, Mentha arvensis and Catharanthus roseus and from the aqueous extracts of Aloe barbadensis and Mentha arvensis. It was observed that nanonoparticles of ethanolic extracts of Azadirachta indica, Carica papaya, Mentha arvensis and Catharanthus roseus exhibited the highest antibacterial activity against Pseudomonas specie, E.coli, Pseudomonas specie and S.typhi, respectively. On the other hand, the nanoparticles of methanolic extracts of Carica papaya, Mentha arvensis and Catharanthus roseus showed the highest inhibition against E.coli, whereas, maximum zone of inhibition of Pseudomonas was observed by the action of methanolic extract of Azadirachta indica. It is also found that nanoparticles of the aqueous extracts of Aloe barbadensis and Mentha arvensis inhibited the pathogenic strains and showed maximum activity against Pseudomonas and E.coli, respectively. Conclusion: The above results indicate that the nanoparticles formed from the extracts of the tested plants have high antimicrobial potential and could be utilized in the preparation of medicines to treat various disorders.

Silver/poly(vinyl alcohol)/graphene hydrogels for wound dressing applications: Understanding the mechanism of silver, antibacterial agent release

AbstractLong‐term wound healing and chronic wound care represent significant challenges for biomaterials science and engineering with many diverse requirements for the wound dressing properties, as well as antibacterial efficacy and antibacterial agent release to prevent and treat persistent infections. Silver nanoparticles, as a wide‐spectrum antibacterial agent that does not induce bacterial resistance, are very convenient for use as an active component in antibacterial hydrogel wound dressing materials with the controlled release ability. In this work, we aim to perform a comprehensive analysis of silver release from poly(vinyl alcohol)‐based hydrogels with electrochemically synthesized antibacterial silver nanoparticles (AgNPs), aimed for wound dressing applications. Different AgNPs concentrations were loaded in hydrogel matrices using the green electrochemical reduction method, and thus synthesized nanocomposite hydrogels were characterized by different techniques (scanning electron microscopy, Fourier‐transform infrared and Raman spectroscopy, and differential scanning calorimetry), in order to assess their physico‐chemical and thermal properties. Silver release was monitored for 28 days in physiologically‐relevant conditions (phosphate buffered medium, pH 7.4, 37°C). The obtained experimental data were evaluated against several theoretical release models (Korsmeyer‐Peppas, Higuchi, Makoid‐Banakar, Kopcha, and early‐time approximation), which confirmed the predominantly diffusion‐controlled mechanism of release. Finally, AgNP‐loaded hydrogels were assessed for antibacterial activity againstStaphylococcus aureusTL andEscherichia coliATCC25922 bacterial strains, to prove their strong potential for wound dressing applications.

Chitosan nanofiber biocomposites for potential wound healing applications: Antioxidant activity with synergic antibacterial effect.

Bacterial wound infection is one of the most common nosocomial infections. The unnecessary employment of antibiotics led to raising the growth of antibiotic‐resistant bacteria. Accordingly, alternative armaments capable of accelerating wound healing along with bactericidal effects are urgently needed. Considering this, we fabricated chitosan (CS)/polyethylene oxide (PEO) nanofibers armed with antibacterial silver and zinc oxide nanoparticles. The nanocomposites exhibited a high antioxidant effect and antibacterial activity against Staphylococcus aureus, Escherichia coli, and Pseudomonas aeruginosa. Besides, based on the results of the cell viability assays, the optimum concentration of ZnONPs and AgNPs in the nanofibrous mats is 0.2% w/v and 0.08% w/v respectively and had no cytotoxicity on fibroblast cells. The scaffold also showed good blood compatibility according to the effects of coagulation time. As well as significant fibroblast migration and proliferation on the wound margin, according to wound‐healing assay. All in all, the developed biocompatible, antioxidant, and antibacterial Ag‐ZnO NPs incorporated CS/PEO nanofibrous mats showed their potential as an effective wound dressing.

Multifunctional Titanium Surfaces for Orthopedic Implants: Antimicrobial Activity and Enhanced Osseointegration.

The use of implants in orthopedics and dental practice is a widespread surgical procedure to treat diverse diseases. However, peri-implantitis due to infections and/or poor osseointegration can lead to metallic implant failure. The aim of this study was to develop a multifunctional coating on titanium (Ti) surfaces, to simultaneously deal with both issues, by combining antibacterial silver nanoparticles (AgNPs) and regenerative properties of lactoferrin (Lf). A simple and cost-effective methodology that allows the direct multifunctionalization of Ti surfaces was developed. The modified surfaces were characterized by atomic force microscopy (AFM), X-ray photoelectron spectroscopy, and contact angle measurements. Additionally, in vitro preosteoblast cell adhesion, cell viability, and differentiation were evaluated. The antibacterial capability of the surfaces was tested against Staphylococcus aureus as a prosthesis infection model strain. Our results showed that Lf adsorbed on both Ti surfaces and Ti surfaces with adsorbed AgNPs. Simultaneously, the presence of Lf and AgNPs notably improved preosteoblast adhesion, proliferation, and differentiation, whereas it reduced the bacterial colonization by 97.7%. Our findings indicate that this simple method may have potential applications in medical devices to both improve osseointegration and reduce bacterial infection risk, enhancing successful implantation and patients' quality of life.