Incorporation Of Silver Nanoparticles Research Articles

Silica-Gel Incorporated Biosynthesized-Silver Nanoparticles for Sustainable Antimicrobial Treatment of Brackish Water Aquaculture

Treatment of brackish water from pathogenic microbes is crucial for sustainable aquaculture production and preventing the spread of infectious diseases. However, the treatment of brackish water is still challenging due to the high salinity and the high antimicrobial resistance. Here, we exploit a facile and effective approach to synthesize silica gel embedded with silver nanoparticles (7–48 nm) for broad-spectrum antimicrobial activity. The incorporation of silver nanoparticles into silica gel (AgNPs@SG) is confirmed by flame atomic absorption spectrometry, X-ray diffraction, N2 physisorption, and transmission electron microscopy. The AgNPs@SG material exhibits wide-spectrum antimicrobial activity against the studied microorganisms (Pseudomonas aeruginosa, Escherichia coli, and Candida albicans) due to preventing the aggregation of silver nanoparticles and their effective contact with the microorganisms. Most importantly, the applicability of the synthesized AgNPs@SG for the microbial treatment of brackish water is investigated on different water samples collected from Manzala Lake. Remarkably, the amount of viable bacteria in the brackish water decreases by about 93% using AgNPs@SG material that not only combats antibiotic-resistant strains but also works under harsh conditions such as multiple-source contamination, high eutrophic state, and salinity.

A step-by-step assessment of the backwashing process impact on the fouling mitigation of blended PVC/PC and nanocomposite PVC/PC/MAg membranes in a membrane bioreactor (MBR) treating pharmaceutical wastewater

Membrane bioreactors are widely used for industrial wastewater treatment. However, membrane fouling is one of the critical problems in applying these systems. fouling mitigation is an essential issue since membrane fouling results in decreased permeability, increased energy consumption, and reduced membrane lifespan which should be addressed in industrial designs. In this study, our objective was to evaluate the filtration performance and fouling behavior of the blended polyvinyl chloride/polycarbonate (PVC/PC) and nanocomposite PVC/PC/modified silver nanoparticles (PVC/PC/MAg) hollow fiber membranes in continuous and intermittent (filtration with backwashing) filtration experiments at constant pressure. Additionally, an experimental module was designed for the backwashing process so that the fouling phenomenon could be investigated step-by-step for both membranes. The performance of the nanocomposite membrane was compared with that of the blended membrane after each backwashing step in terms of flux recovery and fouling resistances. Permeate flux of the blended and nanocomposite membranes at the end of the continuous filtration experiments compared with the initial flux declined by 61% and 48%, respectively. During the intermittent filtration experiments, the average flux of the blended and nanocomposite membranes in the last step decreased by about 16% and 7% in comparison with the first step, respectively. Flux recovery for the nanocomposite membrane at the end of each backwashing step in the intermittent filtration experiment was over 95% resulting in lower permeability decline over the filtration process. Moreover, the present study reveals that incorporating silver nanoparticles into the structure of the PVC/PC membrane results in an increase in permeability and enhancement of antifouling properties, as well as it increases the flux recovery during the backwashing process in MAg-filled nanocomposite membranes.

Therapeutic Application of an Ag-Nanoparticle-PNIPAAm-Modified Eggshell Membrane Construct for Dermal Regeneration and Reconstruction.

Current therapeutic treatments for the repair and/or replacement of damaged skin following disease or traumatic injury is severely limited. The chicken eggshell membrane (ESM) is a unique material: its innate physical and mechanical characteristics offer optimal barrier properties and, as a naturally derived extract, it demonstrates inherent biocompatibility/biodegradability. To further enhance its therapeutic and clinical potential, the ESM can be modified with the thermo-responsive polymer, poly(N-isopropylacrylAmide) (PNIPAAm) as well as the incorporation of (drug-loaded) silver nanoparticles (AgNP); essentially, by a simple change in temperature, the release and delivery of the NP can be targeted and controlled. In this study, ESM samples were isolated using a decellularization protocol, and the physical and mechanical characteristics were profiled using SEM, FT-IR, DSC and DMA. PNIPAAm was successfully grafted to the ESM via amidation reactions and confirmed using FT-IR, which demonstrated the distinctive peaks associated with Amide A (3275 cm−1), Amide B (2970 cm−1), Amide I (1630 cm−1), Amide II (1535 cm−1), CH2, CH3 groups, and Amide III (1250 cm−1) peaks. Confirmation of the incorporation of AgNP onto the stratified membrane was confirmed visually with SEM, qualitatively using FT-IR and also via changes in absorbance at 380 nm using UV-Vis spectrophotometry during a controlled release study for 72 h. The biocompatibility and cytotoxicity of the novel constructs were assessed using human dermal fibroblast (HDFa) and mouse dermal fibroblast (L929) cells and standard cell culture assays. Metabolic activity assessment (i.e., MTS assay), LDH-release profiles and Live/Dead staining demonstrated good attachment and spreading to the samples, and high cell viability following 3 days of culture. Interestingly, longer-term viability (>5 days), the ESM-PNIPAAm and ESM-PNIPAAm (AgNP) samples showed a greater and sustained cell viability profile. In summary, the modified and enhanced ESM constructs were successfully prepared and characterized in terms of their physical and mechanical profiles. AgNP were successfully loaded into the construct and demonstrated a desirable release profile dependent on temperature modulation. Fibroblasts cultured on the extracted ESM samples and ESM-PNIPAAm demonstrated high biocompatibility in terms of high cell attachment, spreading, viability and proliferation rates. As such, this work summarizes the development of an enhanced ESM-based construct which may be exploited as a clinical/therapeutic wound dressing as well as a possible application as a novel biomaterial scaffold for drug development.

Silver Nanoparticle-Incorporated Defect-Engineered Zr-based Metal-Organic Framework for Efficient Multicomponent Catalytic Reactions.

Small-sized silver nanoparticles are incorporated into a thiol-functionalized stable Zr-based metal-organic framework (MOF). Thiol functionalization has been carried out using 2-mercapto benzoic acid (2-MBA) as the modulator, which promotes defect formation in the MOF structure. The incorporation of silver nanoparticles aided by the silver-sulfur interactions in this defective MOF gives rise to catalytic activity. Its catalytic efficiency in the highly atom-efficient A3 coupling reaction has been studied for a variety of substrates with impressive recyclability. The synergistic effect of the electron-rich silver core and electron-deficient surface of the thiol-bonded silver nanoparticle is key for this catalytic reaction.

Characterization of polyamide thin film composite membranes incorporated silver nanoparticles

AbstractIn this study, the polyamide thin film composite membrane surface has been modified by anti‐microbial silver nanoparticles (AgNPs). The membrane surfaces were interwoven with AgNPs by ultraviolet grafting polymerization method using AgNPs with or without poly(ethylene glycol) (PEG). The membrane surface characteristics were determined by scanning electron microscopy–energy dispersive x‐ray spectrometry images, attenuated total reflection–Fourier transforms infrared spectroscopy, water contact angle values, and anti‐bacterial property. The separation performance was determined based on the flux and the ability to remove calcium ions in water. The anti‐biofouling property was appraised through the maintained flux ratios and the irreversible fouling factors of unmodified and modified membranes during 10 h‐filtration of protein bovine serum albumin (BSA) in an aqueous solution, in which, before filtration of BSA, all membranes were immersed in E. coli bacteria solution for 4 days. The results of the experiments corroborated the hydrophilicity and more anti‐microbial property of the membrane surfaces after being incorporated into AgNPs. The water contact angle decreased from around 49° for the unmodified membrane to 36° and 23° for the AgNP‐modified membranes without/with PEG, while no colonies appeared in the medium containing the AgNP‐modified membranes. The separation property of modified membranes was improved, with both membrane flux and antifouling properties, along with the substantial surge of the anti‐biofouling property. After 10 h of BSA filtration, the fluxes of the modified membranes were maintained at 68% and 78% for AgNP‐modified membranes without and with PEG, respectively. Conversely, this value was only 46% for the unmodified one.

Antibacterial, Antifungal and Antiviral Polymeric Food Packaging in Post-COVID-19 Era.

Consumers are now more concerned about food safety and hygiene following the COVID-19 pandemic. Antimicrobial packaging has attracted increased interest by reducing contamination of food surfaces to deliver quality and safe food while maintaining shelf life. Active packaging materials to reduce contamination or inhibit viral activity in packaged foods and on packaging surfaces are mostly prepared using solvent casting, but very few materials demonstrate antiviral activity on foods of animal origin, which are important in the human diet. Incorporation of silver nanoparticles, essential oils and natural plant extracts as antimicrobial agents in/on polymeric matrices provides improved antifungal, antibacterial and antiviral properties. This paper reviews recent developments in antifungal, antibacterial and antiviral packaging incorporating natural or synthetic compounds using preparation methods including extrusion, solvent casting and surface modification treatment for surface coating and their applications in several foods (i.e., bakery products, fruits and vegetables, meat and meat products, fish and seafood and milk and dairy foods). Findings showed that antimicrobial material as films, coated films, coating and pouches exhibited efficient antimicrobial activity in vitro but lower activity in real food systems. Antimicrobial activity depends on (i) polar or non-polar food components, (ii) interactions between antimicrobial compounds and the polymer materials and (iii) interactions between environmental conditions and active films (i.e., relative humidity, oxygen and water vapor permeability and temperature) that impact the migration or diffusion of active compounds in foods. Knowledge gained from the plethora of existing studies on antimicrobial polymers can be effectively utilized to develop multifunctional antimicrobial materials that can protect food products and packaging surfaces from SARS-CoV-2 contamination.

P013 Green synthesis of silver nanoparticles using Trillium govanianum and its antifungal potential against Candida auris

Poster session 1, September 21, 2022, 12:30 PM - 1:30 PM ObjectiveThis study aimed to evaluate the antifungal and anti-biofilm activities of silver nanoparticles synthesized using Trillium govanianum, a trans-Himalayan medicinal plant extract, against multidrug-resistant Candida auris.MethodsSilver nanoparticles (AgNPs) were synthesized by adopting a green approach. Optimization and characterization of TG-AgNPs were carried out using UV-VIS spectroscopy, TEM, and FTIR. Minimum inhibitory concentration (MIC), minimum fungicidal concentration (MFC), and antibiofilm activity of the crude extract, as well as TG-nanoparticles, were evaluated. Furthermore, their effect on cell morphology and cell permeability was also analyzed using FESEM.ResultsCrude extracts of roots of T. govanianum exerted remarkable antifungal activity against multiple strains of Candida auris. The incorporation of silver nanoparticles to plant extract significantly improved the antifungal and antibiofilm activities against the tested strains in a synergistic manner.ConclusionSilver nanoparticles synthesized using Trillium govanianum extract provide eco-friendly, biocompatible nanostructures with antifungal activity and have the potential for use as a therapeutic/nutraceutical agent.

Sulfides mediate the migration of nanoparticle mass out of nanocomposite plastics and into aqueous environments

We show that inorganic sulfides strongly influence transfer (migration) of nanoparticle mass out of polymer nanocomposites (PNCs) and into aqueous environments. We first manufactured two families of PNCs: one incorporating silver nanoparticles (AgNPs) and one incorporating CdSe quantum dots (QDs). Then, we assessed migration out of these PNCs and into aqueous media containing Na2S at concentrations ranging from 0 to 10−4 M. Results show that Na2S strongly suppressed migration of Ag from AgNP-based PNCs: the migration into water spiked with 10−6 M Na2S was 79% less than migration into water without Na2S, and no migration was detected (LOD ≈ 0.01 ng/cm2) in water spiked with Na2S at 10−5 M or 10−4 M. With CdSe QD-based PNCs, Na2S suppressed Cd migration but enhanced Se migration, resulting in only a small net effect on the total QD migration but a large shift of the leachate composition (from favoring Cd by an average of 5.8 to 1 in pure water to favoring Se 9.4 to 1 when Na2S was present at 10−4 M). These results show that common inorganic substances like sulfides may play a strong role in determining the environmental fate of polymer-dispersed nanoparticles and imply that migration tests conducted in purified water may not always accurately reflect migration into real environments.

Comparative Studies on the Electrical Properties of PEDOT:PSS Doped SNP Films and Hydrogels for Medical Electrode Applications

Poly (3,4-ethylene dioxythiophene):poly (styrene sulfonate) (PEDOT:PSS) is a promising conductive polymer to be the next-generation electrode for medical purposes. However, PEDOT:PSS exhibits low conductivity (~1×10−3 S cm−1); hence, incorporating silver nanoparticles (SNP) with PEDOT:PSS will improve the electrical conductivity. This paper aims to investigate the electrical properties differences between PEDOT:PSS doped SNP-based films and hydrogels. The two different states of PEDOT:PSS/SNP serves its particular purpose as an electrode. Initially, the PEDOT:PSS/SNP solution was prepared by homogeneously mixing at constant stirring. Then, the solution was drop-casting onto a glass substrate to produce a film, while another part of the solution was undergoing a freeze-thaw method to produce hydrogel. Surface resistance measurement exhibits lower resistance values for a film (0.11 kΩ) than hydrogel (0.59 kΩ). A scanning electron microscope (SEM) was utilized to observe the morphology of the films, while an optical microscope (OM) observed the surface of the hydrogel since they are in different states. Fourier Transform Infrared (FTIR) spectra display prominent peaks that described the successful blending between PEDOT:PSS and SNP for both films and hydrogels. These findings demonstrate that varying processing methods of preparing PEDOT:PSS/SNP in films or hydrogels may influence its properties like the electrode, which should provide a valuable contribution to the bioelectronic areas.

Influence of Silver Nanoparticles on Selected Properties of Dental Porcelain: An in vitro study

This study was conducted to reveal antibacterial effect of silver nanoparticles incorporation on dental porcelain and its effect on flexural strength and surface hardness of porcelain.

In Vitro Study on Effect of Zinc Oxide Nanoparticles on the Biological Activities of Croton tiglium L. Seeds Extracts.

Croton tiglium L. seeds were studied against colon cancer induced chemically in rats after incorporating silver nanoparticles (Ag-NPs) but the body has no the ability to discrete silver or silver ions. Therefore, the present study was designed to reveal the biological activities of different C. tiglium L. seeds extracts incorporated with zinc oxide nanoparticles (ZnO-NPs). It was found that C. tiglium L. seeds provided with high contents of total protein (27.43 g/100g), carbohydrate (18.29 g/100 g) and lipid (46.31 g/100 g). The chromatographic techniques revealed that concentrations of the predominant compounds increased in all studied extracts (ethanolic, aqueous and petroleum ether) after incorporating ZnO-NPs. The in vitro biological activities showed that the aqueous extract possessed the highest antioxidant and scavenging activities. It exhibited the highest inhibitory effect on α-amylase (41.89%) and acetyl cholinesterase (AChE) (23.00%) in addition to its higher anti-arthritic activity. All the biological activities increased after incorporating ZnO-NPs. It showed the highest cytotoxic activity that increased after incorporating ZnO-NPs against human colon carcinoma (CACO-2) cells. Therefore, this extract was selected for undergoing further studies on CACO-2 cells. The aqueous extract incorporated with ZnO-NPs arrested growth of CACO-2 cells at G2/M and increased percentage of total apoptotic cells and necrosis. The median lethal dose (LD50) showed that the extracts incorporated with ZnO-NPs were safer than the native extracts. The study showed that the aqueous extract was the most active extract that consequently exhibited promising biological activities after incorporating ZnO-NPs.

Fabrication and characterization of inner selective antibiofouling forward osmosis hollow fiber membranes for simultaneous wastewater treatment and desalination

Forward osmosis (FO) hollow-fiber membranes were prepared by in situ thin layer assembly of polyethyleneimine (PEI) on antifouling PES-based porous nanocomposite membranes during membrane formation by spinning and phase inversion, via incorporation of surface-modified silver nanoparticles (NPs) in the dope solution and addition of PEI in the bore liquid; after cross-linking with glutaraldehyde the FO selective layer was obtained at the lumen surface while the shell surface had ultrafilter (UF) properties. This design enabled the utilization of the FO membranes in active layer facing draw solution (DS) orientation to employ maximum effective osmotic pressure, while the UF layer in combination with the antibacterial NPs was supposed to reduce fouling by the wastewater used as feed solution (FS). The quality of the active layer assembly was characterized using atomic force microscopy and scanning electron microscopy analyses, as well as salt rejection, structural parameter (S), and molecular weight cut-off (MWCO) measurements. The separation performance of these membranes was evaluated in an osmotic membrane bioreactor (OMBR) system, showing for the best FO nanocomposite membranes less than 10% fouling and flux reduction over 5 cycles of operation over a total period of 5 days. The best-suited membrane showed promising separation performance in the OMBR system by providing 43.4 LMH water flux and only around 0.2 g/l specific reverse salt flux (SRSF) with 1 M NaCl and DI water serving as DS and feed, respectively. This study focused also on distinctive performance criteria in combined FO and OMBR systems, such as the membrane’s potential in a pretreatment step of brine streams (used as DS) to provide proper feed composition for RO units and introduced a new specific performance index (SPI) for better characterization of FO membranes which summarizes all essential characteristics of the membrane application, instead of using existing structural parameter equations for membrane characterization. The best-suited FO membrane offered an SPI of 778.2 gl−1 m−2 h−1, meaning 778.2 g/l reduction of TDS in DS per unit membrane surface area per hour.

Applications of Silver Nanoparticles in Pediatric Dentistry: An Overview.

Nanoscience and nanotechnology are emerging fields involved in the synthesis and application of nanoscale materials and structures. Metallic nanoparticles and metallic oxide are being used extensively in dentistry as they interfere with bacterial metabolism and prevent biofilm formation. AgNPs are a class of zero-dimensional materials with distinctive morphologies. The metallic nanoparticles demonstrate the significant antimicrobial activity by ion release, oxidative stress induction, and non-oxidative mechanisms. Metallic silver has been known for its antimicrobial activity since ancient times. Through the years, silver-containing compounds have been used in various forms to treat several medical conditions. Incorporating silver nanoparticles into dental materials may enhance the mechanical features and antibacterial properties of dental materials. Therefore, an increasing number of dental materials with the inclusion of silver nanoparticles are being developed that improve the overall oral health status of patients. This paper aims to review the literature on specific characteristics of silver nanoparticles and their applications in pediatric dentistry.

Physical and Mechanical Characterization of a Functionalized Cotton Fabric with Nanocomposite Based on Silver Nanoparticles and Carboxymethyl Chitosan Using Green Chemistry

Cotton is the most widely used natural fiber for textiles but its innate capacity to absorb moisture, retain oxygen, and high specific surface area make it more prone to microbial contamination, becoming an appropriate medium for the growth of bacteria and fungi. In recent years, the incorporation of silver nanoparticles in textile products has been widely used due to their broad-spectrum antibacterial activity and low toxicity towards mammalian cells. The aim of the current study is to synthesize and characterize a nanocomposite based on silver nanoparticles and carboxymethyl chitosan (AgNPs-CMC), which was utilized to provide a functional finish to cotton fabric. The scanning electron microscope (SEM) to produce a scanning transmission electron microscope (STEM) image showed that the nanocomposite presents AgNPs with a 5–20 nm size. The X-ray diffraction (XRD) analysis confirmed the presence of silver nanoparticles. The concentration of silver in the functionalized fabric was evaluated by inductively coupled plasma optical emission spectrometry (ICP-OES), which reported an average concentration of 13.5 mg of silver per kg of functionalized fabric. SEM showed that silver nanoparticles present a uniform distribution on the surface of the functionalized cotton fabric fibers. On the other hand, by infrared spectroscopy, it was observed that the functionalized fabric variation (compared to control) had a displaced peak of intensity at 1594.32 cm−1, corresponding to carboxylate anions. Similarly, Raman spectroscopy showed an intense peak at 1592.84 cm−1, which corresponds to the primary amino group of carboxymethyl chitosan, and a peak at 1371.5 cm−1 corresponding to the carboxylic anions. Finally, the physical and mechanical tests of tensile strength and color index of the functional fabric reported that it was no different (p ˃ 0.05) than the control fabric. Our results demonstrate that we have obtained an improved functionalized cotton fabric using green chemistry that does not alter intrinsic properties of the fabric and has the potential to be utilized in the manufacturing of hospital garments.

AgNP anchored carbon dots and chitin nanowhisker embedded soy protein isolate films with freshness preservation for active packaging

Biodegradable substitutes to the commonly practiced packaging materials are always in high demand. Active biopolymer film was obtained from soy-protein isolate (SPI) and the antibacterial properties were introduced by incorporating silver nanoparticles. Active bio-composite films incorporating silver nanoparticles (AgNP) are much sought after in the food packaging industry owing to their ability to extend the shelf life of fresh foods. But the toxicity of the ingredients used for preparation (mainly the reducing agents) and the poor stability limits their usage for the aforementioned application. Herein, to counter these limitations, we have adopted an environment-friendly method where carbon dot (CD) prepared from soy protein isolate was used to prepare AgNPs. AgNPs (1% wt.) and different concentrations of chitin nano whisker (CNW) (2–10% wt.) were added to soy protein isolate to fabricate nanocomposite films. The subsequent effect on the latter’s tensile property, moisture content, thermal property and morphological characteristics were noted. Here, for the first time, the steam explosion technique was used for the preparation of CNW which resulted in highly crystalline CNW with good antibacterial properties. It was observed that the mechanical strength and thermal stability of SPI film were significantly increased and the moisture content decreased with the addition of CNW and AgNP. The synergistic effect of AgNP and CNW imparted excellent antioxidant, antibacterial and antifungal properties to the SPI film thus enabling the SPI film to extend the shelf life of the food material that was packed using the same. Commercial production of such SPI films would revolutionize the food packing industry given its health benefits and its cost-effectiveness.

Combined Effect of Layered Double Hydroxides and Nano silver on Bacterial Inhibition and Gas Barrier Properties of Chitosan Grafted Polyacrylonitrile Nanocomposites

ABSTRACT Herein, chitosan-grafted-poly(acrylonitrile) (CS-g-PAN) nanocomposites are prepared by emulsifier-free emulsion polymerization technique with dispersion of layered double hydroxides(LDHs) and nano silver(AgNPs). The interactions of AgNPs and LDH with co-polymeric matrix are investigated by FTIR and XRD. It is noticed that LDH platelets are intercalated and partially exfoliated within the copolymeric matrices. Dispersion of fillers creates tortuous path which enhances the gas barrier properties up to seven folds. Antibacterial behavior of nanocomposites is achieved due to incorporation of silver nanoparticles and LDH. Thermal stability, chemical resistance and biodegradable properties of the synthesized material are also increased due to combined effect of LDH and AgNPs.

Assessment of Shear Bond Strength and Cytotoxicity of Orthodontic Adhesive with Addition of Silver Nanoparticles in Varying Concentrations

Background: Prolonged treatment with fixed orthodontic appliances tend to compromise oral hygiene maintenance in patients, increasing their susceptibility to white spot lesions and caries. Incorporating silver nanoparticles into adhesives and orthodontic appliances is known to improve its antimicrobial properties. Aim and objectives: The aim of the present study was to assess and compare the bond strength of orthodontic adhesive when Silver Nanoparticles were added in varying concentrations and also to assess their cytotoxicity on periodontal ligament fibroblasts. Materials and methods: Various concentrations of silver nanoparticles (1%, 5%, 10%w/w) were incorporated into Transbond XT composite adhesive and their shear bond strength and cytotoxicity were compared to a control group. Brackets were bonded to extracted premolar teeth and shear bond strength was assessed using Instron Universal Testing Machine. The viability of periodontal ligament fibroblasts was assessed after incubating with the experimental composite for 24 hours and 1 week using MTT assay. Results: There was a decrease in the shear bond strength when 1% and 5% of silver nanoparticles were incorporated into the adhesive.However, it was within the clinically recommended range for bonding brackets. When the concentration was increased to 10%, the SBS was not acceptable for orthodontic bonding. The composite incorporated with silver nanoparticles was cytotoxic to fibroblasts at all concentrations at both time intervals. Conclusion: The shear bond of orthodontic adhesive with nanosilver is comparable to plain transbond XT in low concentrations, however, the addition of silver nanoparticles seems to increase the time-bound cytotoxicity of orthodontic adhesive.

Antibacterial and Antifungal Activity of Functionalized Cotton Fabric with Nanocomposite Based on Silver Nanoparticles and Carboxymethyl Chitosan

Cotton is the most widely used natural fiber for textiles; however, the capacity of cotton fibers to absorb large amounts of moisture, retain oxygen, and have a high specific surface area makes them more prone to microbial contamination, becoming an appropriate medium for the growth of bacteria and fungi. In recent years, the incorporation of silver nanoparticles in textile products has been widely used due to their broad-spectrum antibacterial activity and low toxicity towards mammalian cells. The aim of the current study is to continue the assessment of our developed nanocomposite and evaluate the antibacterial and antifungal activity of the nanocomposite based on silver nanoparticles and carboxymethyl chitosan (AgNPs-CMC) against Escherichia coli, Staphylococcus aureus, and Candida albicans, evaluated by the well diffusion method. The antibacterial activity against E. coli and S. aureus was also evaluated by the qualitative method of inhibition zone and the quantitative method of colony counting. Likewise, the antifungal activity of the functionalized fabric against Candida albicans and Aspergillus niger was determined by the inhibition zone method and the antifungal activity method GBT 24346-2009, respectively. The functionalized fabric showed 100% antibacterial activity against E. coli and S. aureus and good antifungal activity against C. albicans and A. niger. Our results indicate that the functionalized fabric could be used in garments for hospital use to reduce nosocomial infections.

One-Pot and Green Preparation of Phyllanthus emblica Extract/Silver Nanoparticles/Polyvinylpyrrolidone Spray-On Dressing.

A spray-on wound dressing has many benefits, including easy and quick administration to broad and uneven wounds, better interface with the wound site, adhesion without additional dressing, and multiple applications in a portable package. By limiting direct contact with the wound site, such a design can prevent wound damage during treatment. This study revealed a simple, one-pot synthesis of spray-on wound dressing relying on polyvinylpyrrolidone solution incorporating silver nanoparticles as a broad-spectrum antibacterial agent and wound-healing antioxidant Phyllanthus emblica extract. Silver nanoparticles were synthesized in situ using Phyllanthus emblica extract as a biogenic reducing agent. Polyvinylpyrrolidone was employed as a film-forming agent to create an adhesive hydrogel-based dressing matrix to provide moisture and establish a shielding barrier for the wound bed as well as to regulate the release of fruit extract. In vitro tests revealed that the produced dressing film had a controlled release of the fruit extract, high antioxidant activity, and a good antibacterial action against S. aureus, P. aeruginosa, E. coli, and MRSA. Additionally, a biocompatibility study has shown that both human fibroblasts and keratinocytes are unaffected by the dressing film. Based on established findings, the current spray-on solution might be a potential option for antibacterial wound dressing.

Effect of silver nanoparticle on properties of maxillofacial silicone elastomer material

Aim: The purpose of this study was to evaluate the impact of silver nanoparticle incorporation into maxillofacial silicone material on its hardness tear strength and color stability. Methodology: A total of 90 silicone specimens were fabricated. The control samples were fabricated with- out silver nanoparticles and test samples were fabricated with 20 ppm concentration of silver nanoparticles. Digital shore A hardness tests was used to measure hardness, for tear strength the specimen was placed in the jaws of the universal testing machine and stretched at a rate of 500 ram/rain, for color stability Spectrophotometer had been employed. The independent sample’s “t” test was used to test significant differences. Results: The mean difference for hardness between control and test group was 0.54 and t value was 2.08 and ( p < 0.05).tear strength 0.66 and “t”value was 0.93 and ( p < 0.05) and for color stability it was -0.02 and t value was -0.92 and ( p < 0.05). Conclusion: The present study findings suggest that addition of silver nanoparticles at 20 ppm concentration decreased the hardness of silicone elastomer, and it did not affect tear strength and color stability.