Green Synthesis of Silver Nanoparticles from Syzygium cumini (L.) Skeels Seed Extract and their Potential Medicinal Applications.

AIM: Nanotechnology is considered as one of the fastest-developing areas in the biomedicine field. Hence, the green synthesis of silver nanoparticles from Syzygium cumini seed extract was carried out in this study. METHODOLOGY: The synthesized nanoparticles were characterized by UV-Vis spectroscopy, FTIR (Fourier transform infrared), FE-SEM (Field Emission scanning electron microscopic), AFM (Atomic Force Microscope), XRD (X-ray diffraction), and EDX (Energy dispersive X-Ray). Their antioxidant and anti-inflammatory activity were evaluated by DPPH (2,2-diphenyl-1- picrylhydrazyl), PM (Phosphomolybdenum) assay, and albumin denaturation assay. Further, the antibacterial activity of the nanoparticles was studied against Gram-positive and Gram-negative bacteria using the agar well diffusion method. In addition, the antidiabetic activity of nanoparticles was studied by α-amylase and α-glucosidase inhibition assays. RESULTS: The surface plasmon resonance at 430 nm confirmed the formation of silver nanoparticles. They were stable and spherical in shape, with sizes ranging from 30 to 90 nm. The DPPH inhibition % of silver nanoparticles varied from 7.91±0.39% to 68.35±0.76%. The % inhibition of albumin denaturation was comparable to the diclofenac. Further, the results of antibacterial activity revealed that the zone of inhibition for all the test bacteria varied from 14.33±0.58 to 25.33±0.58 mm, where B. cereus was more susceptible. In addition, the % inhibition of α-amylase and α-glucosidase varied from 19.91±0.15% to 61.43±0.31% and 15.26±0.11% to 55.38±0.20%, respectively. CONCLUSION: This study is the first attempt of utilizing the silver nanoparticles synthesized from S. cumini seed extract for antidiabetic activity. The study suggests that these nanoparticles could be well utilized in pharmaceutical industries as an efficient antioxidant, anti-inflammatory, antibacterial, and antidiabetic drug.

Formulation of Garlic Essential Oil-assisted Silver Nanoparticles and Mechanistic Evaluation of their Antimicrobial Activity against a Spectrum of Pathogenic Microorganisms.

BACKGROUND: The synthesis of nanoparticles using the principle of green chemistry has achieved huge potential in nanomedicine. Here, we report the synthesis of silver nanoparticles (Ag- NPs) employing garlic essential oil (GEO) due to wide applications of GEO in the biomedical and pharmaceutical industry. OBJECTIVE: This study aimed to synthesise garlic essential oil-assisted silver nanoparticles and present their antimicrobial and antibiofilm activities with mechanistic assessment. METHOD: Initially, the formulation of AgNPs was confirmed using different optical techniques, such as XRD, FT-IR, DLS, zeta potential, SEM, and EDX analysis, which confirmed the formulation of well-dispersed, stable, and spherical AgNPs. The antimicrobial and antibiofilm activity of GEO-assisted AgNPs was evaluated against a spectrum of pathogenic microorganisms, such as Gram-positive (S. aureus and B. subtilis) and Gram-negative (E. coli and P. aeruginosa) bacteria. RESULTS: The AgNPs exhibited remarkable antimicrobial and anti-biofilm activity against all tested strains. The mechanism behind the antimicrobial activity of AgNPs was explored by estimating the amount of reactive oxygen species (ROS) generated due to the interaction of AgNP with bacterial cells and observing the morphological changes of bacteria upon AgNP interaction. CONCLUSION: The findings of this study concluded that ROS generation due to the interaction of AgNPs with bacterial cells put stress on bacterial membranes, altering the morphology of bacteria, exhibiting remarkable antimicrobial activity, and preventing biofilm formation.

Novel electrochemiluminescence sensing platform for ultrasensitive detection of malathion residue in tea based on SiO2NSs doped Luminol/AgNPs as a signal amplification strategy.

To address the potential hazards of organophosphorus pesticides (OPs) residues in tea, an electrochemiluminescence (ECL) aptasensor based on functionalized nanomaterials was constructed in this work. Firstly, gold nanoparticles (AuNPs) were attached on the surface of multi-walled carbon nanotubes (MWCNTs) by the constant potential electrodeposition to form a compound, and it was utilized to provide excellent immobilization sites for complementary DNA (cDNA). Subsequently, composite nanomaterials were synthesized by a one-pot method with aminated Luminol/silver nanoparticles@silica nanospheres (NH2-Luminol/Ag@SiO2NSs). Finally, NH2-Luminol/Ag@SiO2NSs was combined with a malathion aptamer (Apt) to obtain signal probes (SPs) for the construction of an aptasensor. The aptasensor had a wide linear range (1×10-3-1×103 ng/mL) and a low limit of detection (LOD) (0.3×10-3 ng/mL). It had the virtues of high sensitivity, wonderful stability and excellent specificity, which could be used for the detection of malathion residue in tea. The work provides a proven way for the construction of a rapid and ultrasensitive aptasensor with low-cost.

Biosynthesis of bacteriocin BacZY05-silver nanoconjugates and evaluation of their antibacterial properties.

Bacteriocins are antimicrobial peptides produced by bacteria to prevent the growth of pathogens. Combining bacteriocins with metal nanoparticles, like silver nanoparticles (AgNPs), has developed into a viable strategy to get over bacteriocin limitations. In this study, bacteriocin BacZY05 was extracted from Bacillus subtilis ZY05 and purified using various techniques. The resulting purified bacteriocin was then combined with silver nanoparticles to form bacteriocin silver nanoconjugates (BacZY05-AgNPs). The physicochemical properties of the BacZY05-AgNPs were characterized using various analytical techniques. The mean diameter of the synthesized AgNPs was approximately 20-60 nm with an oval or spherical shape. The antimicrobial activity of the BacZY05-AgNPs was evaluated against several indicator strains by their zone of inhibition (ZOI), using the agar well diffusion method. Compared to bacteriocin (ZOI- 13 to 20 mm) and AgNPs (ZOI- 10-22 mm) alone, the antibacterial activity data demonstrated a 1.3-1.5-fold increase in the activity of bacteriocin-nanoconjugates (ZOI- 22 to 26 mm). For Staphylococcus aureus MTCC3103 and Klebsiella pneumoniae MTCC109, BacZY05-capped AgNPs exhibited the lowest minimum inhibitory concentration (MIC), measuring 10.93 µg/mL. For Salmonella typhi NCIM2501, the MIC was 28.75 µg/mL. The highest MIC value was 57.5 µg/mL for Escherichia coli DH5α and Vibrio cholerae MTCC3909. With BacZY05-capped AgNPs, the lowest minimum bactericidal concentration (MBC) of 28.75 µg/mL was observed for Staphylococcus aureus MTCC31003. In the cases of Salmonella typhi NCIM2501 and Klebsiella pneumoniae MTCC109 concentration was 57.5 µg/mL. Vibrio cholerae MTCC3909 and Escherichia coli DH5α had the highest MBC values at 115 µg/mL.

Bacteria-Derived Cellulose Membranes Modified with Graphene Oxide-Silver Nanoparticles for Accelerating Wound Healing.

This study reports on the modification of bacterial cellulose (BC) membranes produced by static fermentation of Komagataeibacter xylinus bacterial strains with graphene oxide-silver nanoparticles (GO-Ag) to yield skin wound dressings with improved antibacterial properties. The GO-Ag sheets were synthesized through chemical reduction with sodium citrate and were utilized to functionalize the BC membranes (BC/GO-Ag). The BC/GO-Ag composites were characterized to determine their surface charge, morphology, exudate absorption, antimicrobial activity, and cytotoxicity by using fibroblast cells. The antimicrobial activity of the wound dressings was assessed against Staphylococcus aureus, Escherichia coli, and Pseudomonas aeruginosa. The results indicate that the BC/GO-Ag dressings can inhibit ∼70% of E. coli cells. Our findings also revealed that the porous BC/GO-Ag antimicrobial dressings can efficiently retain 94% of exudate absorption after exposure to simulated body fluid (SBF) for 24 h. These results suggest that the dressings could absorb excess exudate from the wound during clinical application, maintaining adequate moisture, and promoting the proliferation of epithelial cells. The BC/GO-Ag hybrid materials exhibited excellent mechanical flexibility and low cytotoxicity to fibroblast cells, making excellent wound dressings able to control bacterial infectious processes and promote the fast healing of dermal lesions.

Release of ions enhanced the antibacterial performance of laser-generated, uncoated Ag nanoparticles.

Identifying the antibacterial mechanisms of elemental silver at the nanoscale remains a significant challenge due to the intertwining behaviors between the particles and their released ions. The open question is which of the above factor dominate the antibacterial behaviors when silver nanoparticles (Ag NPs) with different sizes. Considering the high reactivity of Ag NPs, prior research has primarily concentrated on coated particles, which inevitably hinder the release of Ag+ ions due to additional chemical agents. In this study, we synthesized various Ag NPs, both coated and uncoated, using the laser ablation in liquids (LAL) technique. By analyzing both the changes in particle size and Ag+ ions release, the impacts of various Ag NPs on the cellular activity and morphological changes of gram-negative (E. coil) and gram-positive (S. aureus) bacteria were evaluated. Our findings revealed that for uncoated Ag NPs, smaller particles exhibited greater ions release efficiency and enhanced antibacterial efficacy. Specifically, particles approximately 1.5 nm in size released up to 55 % of their Ag+ ions within 4 h, significantly inhibiting bacterial growth. Additionally, larger particles tended to aggregate on the bacterial cell membrane surface, whereas smaller particles were more likely to be internalized by the bacteria. Notably, treatment with smaller Ag NPs led to more pronounced bacterial morphological changes and elevated levels of intracellular reactive oxygen species (ROS). We proposed that the bactericidal activity of Ag NPs stems from the synergistic effect between particle-cell interaction and the ionic silver, which is dependent on the crucial parameter of particle size.

Rapid detection of bactericidal efficacy of nanoparticles coated polyurethane foam by synchronous fluorescence spectroscopy.

The ability of right-angled synchronous fluorescence spectroscopy (SFS) was explored to analyse the bacterial load in water treated with green synthesized silver nanoparticles (AgNPs) coated polyurethane foam (PUF). Gram negative (Escherichia coli, Pseudomonas aeruginosa) and Gram positive (Staphylococcus aureus) bacteria cultured in nutrient broth were diluted in autoclaved water containing NPs-coated PUF. The survival rate of S. aureus and E. coli lowered after ten minutes as compared to P. aeruginosa; however, after thirty minutes, the percentage viability dropped and recorded as 3.4%, 0.9%, and 0.1% for E. coli, P. aeruginosa and S. aureus respectively in the treated suspensions. No spectral change was observed in the fluorescence emission from the positive control and treated bacterial suspension owing to the masking effect of the emission from nutrient broth. In parallel, SF spectra recorded for directly picked bacterial colony dissolved in water showed remarkable drop in tryptophan emission after treatment with NPs-coated PUF. The SF data changes were assisted by hierarchical cluster analysis, which also made it possible to distinguish between positive control and treated bacterial suspensions. SFS has shown to be a reliable substitute for the culture plate approach for the quick identification of bacterial contamination in water.

Biosynthesis of silver nanoparticle using Bacillus licheniformis culture-supernatant for combating pathogenic biofilms.

Bacterial biofilms pose a significant threat to healthcare due to their recalcitrance to antibiotics and disinfectants. This study explores the anti-biofilm potential of Bacillus licheniformis cell-free culture supernatant (CFS) and its derived silver nanoparticles (bSNPs) against Staphylococcus aureus and Pseudomonas aeruginosa. The CFS exhibited potent anti-biofilm activity against both bacterial species, even at low concentrations, while devoid of significant bactericidal effects, mitigating resistance risks. Characterization studies revealed the non-proteinaceous nature and thermal stability of the CFS's anti-biofilm agent, suggesting a robust and heat-resistant structure. Green synthesis of bSNPs from CFS resulted in nanoparticles with significant anti-biofilm properties, particularly against P. aeruginosa, indicating differences in susceptibility between the bacterial species. Epifluorescence microscopy confirmed bSNPs' ability to inhibit and partially disrupt biofilm formation without inducing cellular lysis. The study highlights the potential of B. licheniformis CFS and bSNPs as promising biofilm control agents, offering insights into their mechanisms of action and broad-spectrum efficacy. Further research elucidating the underlying molecular mechanisms and identifying specific bioactive compounds is warranted for the translation of these findings into clinically relevant applications for combating biofilm-associated infections.

Composite with Silver Nanoparticles and Oregano Essential Oil-Loaded Nanoparticles Intended for Wound Healing.

PURPOSE: Since wounds are a primary source of infection, it is desirable to have a wound dressing that prevents infectious processes during the tissue regeneration phase. In this regard, silver nanoparticles, oregano essential oil, and chitosan have been utilized due to their antimicrobial activity. This work focused on the preparation of a composite containing these three components, intended to provide protection for wounds, especially by exerting antimicrobial effects. METHODS: A composite based on chitosan nanoparticles loaded with oregano essential oil (OEO) and silver nanoparticles was fabricated through the casting-solvent evaporation method. The films were prepared from a suspension of chitosan nanoparticles. The nanoparticles were characterized by size and entrapment efficiency. The surface of the films was observed by SEM, and the mechanical resistance, occlusive capacity, and antimicrobial activity against S. aureus, E. coli, and P. aeruginosa were evaluated. The release of OEO from the films was studied using Franz-type cells. RESULTS: A composite was successfully prepared from a dispersion of OEO-loaded chitosan nanoparticles (147.8 nm, PDI = 0.35; entrapment efficiency = 80.9 %; loading capacity = 38 %) and silver nanoparticles (19.6 nm, PDI = 0.4). A film could be formed that made the composite by pouring the chitosan nanoparticle dispersion directly into molds. The composite presented advantageous characteristics, such as being semi-occlusive (occlusion factor ~ 40 % and reduction in TEWL of 18 %), allowing the sustained release of OEO (about 0.2 mgCm-2 h-1 during 8 h), and having antimicrobial activity for the three strains evaluated. CONCLUSION: The prepared composite can be considered a potential candidate for dressing materials intended to prevent and treat wound infections.

Oppositely-charged silver nanoparticles enable selective SERS molecular enhancement through electrostatic interactions.

Label-free surface-enhanced Raman spectroscopy (SERS) has attracted extensive attention as an emerging technique for molecular phenotyping of biological samples. However, the selective enhancement property of SERS mediated by complicated interactions between substrates and analytes is unfavorable for molecular profiling. The electrostatic force is among the most dominating interactions that can cause selective adsorption of molecules to charged substrates. This means if only negatively- or positively-charged SERS substrates are applied, then considerable SERS information from a portion of analytes would be lost, hindering comprehensive SERS sensing. In this work, we utilize both negatively- and positively-charged colloidal silver (Ag) nanoparticles (NPs) to detect various charged molecules. The negatively-charged citrate-stabilized Ag and the positively-charged Ag prepared via a cetyltrimethyl-ammonium chloride-based charge reversal protocol have been adopted as SERS substrates. The Ag NPs are all relatively well-dispersed with good uniformity. After applying the oppositely-charged NPs to the detection of charged molecules, we find the SERS results explicitly demonstrate the electrostatically-driven SERS selective enhancement, which is further supported and clarified by molecular electrostatic potential calculations. Our work highlights the importance of developing SERS substrates modified with appropriate surface charges for various analytes, and enlightens us that potentially more molecular SERS information can be acquired from complex bio-samples using combinations of oppositely-charged substrates.

Chemical fingerprinting, antimicrobial, antioxidant, anti-inflammatory, and anticancer potential of greenly synthesized silver nanoparticles from pistachio (Pistacia vera) nuts and senna (Cassia angustifolia Vahl.) leaves.

There is a growing interest in standardizing the biocompatible, cost-effective, and eco-friendly manufacturing techniques for metallic nanostructures due to their widespread applications in the industrial and medical sectors. In recent decades, green synthesis has been proven as the most suitable technique for synthesizing metal nanoparticles. The present research study investigates the use of Cassia angustifolia (senna) leaves and Pistacia vera (Pistachio) nuts to prepare crude aqueous extracts, ethanolic extracts, and biogenic silver nanoparticles (AgNPs). The prepared aqueous extracts were used as reducing, stabilizing, and capping agents for the production of silver nanoparticles. These AgNPs were characterized by scanning electron microscopy (SEM), Fourier-transform infrared spectroscopy (FTIR), and ultraviolet-visible (UV-Vis) spectroscopy. The outcomes validated the formation of stable AgNPs with bioactive functional components. In vitro antibacterial, anticancer, anti-inflammatory, and antioxidant potentials were assessed by Kirby-Bauer disk diffusion test, MIC test, MBC test, MTT assay, BSA denaturation inhibition assay, and DPPH antioxidant assay, respectively. Results confirmed that the tested plant extract possesses a variety of bioactive compounds with various biological activities and is therapeutically effective. These findings verified that C. angustifolia and P. vera are promising bioresources for the synthesis of therapeutic extracts and nanostructures with commendable therapeutic potency.

Pongamia pinnata seed extract-mediated green synthesis of silver nanoparticle loaded nanogel for estimation of their antipsoriatic properties.

This research describes the eco-friendly green synthesis of silver nanoparticles employing Pongamia pinnata seed extracts loaded with nanogel formulations (AgNPs CUD NG) to improve the retention, accumulation, and the penetration of AgNPs into the epidermal layer of psoriasis. AgNPs were synthesized using the Box-Behnken design. Optimized AgNPs and AgNPs CUD NG were physico-chemically evaluated using UV-vis spectroscopy, SEM, FT-IR, PXRD, viscosity, spreadability, and retention studies. It was also functionally assessed using an imiquimod-induced rat model. The entrapment efficiency of AgNPs revealed ~ 79.35%. Physico-chemical parameters announced the formation of AgNPs via surface plasmon resonance and interaction between O-H, C = O, and amide I carbonyl group of protein extract and AgNO3. Optimized AgNPs showed spherical NPs ~ 116 nm with better physical stability and suitability for transdermal applications. AgNPs CUD NG revealed non-Newtonian, higher spreadability, and better extrudability, indicating its suitability for a transdermal route. AgNPs CUD NG enhanced the retention of AgNPs on the psoriatic skin compared to normal skin. Optimized formulations exhibit no irritation by the end of 72 h, indicating formulation safety. AgNPs CUD NG at a dose of 1 FTU showed significant recovery from psoriasis with a PASI score of ~ 0.8 compared to NG base and marketed formulations. Results indicated that seed extract-assisted AgNPs in association with CUD-based NG formulations could be a promising nanocarrier for psoriasis and other skin disorders.

Silver-enriched microdomain patterns as advanced bactericidal coatings for polymer-based medical devices.

Today, it would be difficult for us to live a full life without polymers, especially in medicine, where its applicability is constantly expanding, giving satisfactory results without any harm effects on health. This study focused on the formation of hexagonal domains doped with AgNPs using a KrF excimer laser (λ=248 nm) on the polyetheretherketone (PEEK) surface that acts as an unfailing source of the antibacterial agent - silver. The hexagonal structure was formed with a grid placed in front of the incident laser beam. Surfaces with immobilized silver nanoparticles (AgNPs) were observed by AFM and SEM. Changes in surface chemistry were studied by XPS. To determine the concentration of released Ag+ ions, ICP-MS analysis was used. The antibacterial tests proved the antibacterial efficacy of Ag-doped PEEK composites against Escherichia coli and Staphylococcus aureus as the most common pathogens. Because AgNPs are also known for their strong toxicity, we also included cytotoxicity tests in this study. The findings presented here contribute to the advancement of materials design in the biomedical field, offering a novel starting point for combating bacterial infections through the innovative integration of AgNPs into inert synthetic polymers.

Implementation of green-assessed nanotechnology and quality by design approach for development of optical sensor for determination of tobramycin in ophthalmic formulations and spiked human plasma.

A fast eco-friendly colorimetric method was developed for the determination of Tobramycin in drug substance, ophthalmic formulations, and spiked human plasma using silver nanoparticles optical sensor. Even though tobramycin is non-UV-visible absorbing, the developed method is based on measuring the absorbance quenching of silver nanoparticles resulting from the interaction with tobramycin. Different factors affecting the absorbance intensity were studied as; silver nanoparticle concentration, pH, buffer type, and reaction time using quality by design approach. Validation of the proposed method was performed according to ICH guidelines and was found to be accurate, precise, and sensitive. The linearity range of tobramycin was 0.35-4.0 µg/mL. The optical sensor was successfully applied for the determination of Tobramycin in ophthalmic formulations and spiked human plasma without pre-treatment. Additionally, the binding between Tobramycin and PVP- capped silver nanoparticles was studied using molecular docking software. The method was assessed and compared to colorimetric reported methods for the green character using Green Analytical Procedure Index (GAPI) and Analytical GREEnness calculator (AGREE) tools and found to be greener.

Synergistic Enhancement of Electron Dynamics and Optical Properties in Zeolitic Imidazolate Framework-8-Derived Zinc Oxide via Surface Plasmon Resonance Effects of Silver Nanoparticles under UV Irradiation.

This study investigates the surface plasmon resonance (SPR)-induced UV photoresponse of zinc oxide (ZnO) derived from zeolitic imidazolate framework-8 (ZIF-8) to assess the influence of silver nanoparticles (Ag NPs) on the photoresponse behavior of metal-organic framework (MOF)-derived ZnO. The initial synthesis involved a thermal treatment in air to convert ZIF-8 into ZnO. We noted enhanced optical absorption both in the UV and visible spectra with the deposition of Ag NPs onto the ZIF-8-derived ZnO. Additionally, the presence of Ag NPs in the ZnO resulted in a substantial increase in current, even without any light exposure. This increase is attributed to the transfer of electrons from the Ag NPs to the ZnO. Photocurrent measurements under UV illumination revealed that the photocurrent with Ag NPs was significantly higher-by two orders of magnitude-compared with that without Ag NPs. This demonstrates that SPR-induced absorption markedly boosted the photocurrent, although the current rise and decay time constants remained comparable to those observed with ZnO alone. Although Ag NPs contribute electrons to ZnO, creating a "pre-doping" effect that heightens baseline conductivity (even in the absence of light), this does not necessarily alter the recombination dynamics of the photogenerated carriers, as indicated by the similar rise and decay time constants. The electron transfer from Ag to ZnO increases the density of charge carriers but does not significantly influence their recombination.

Hyaluron-Based Bionanocomposites of Silver Nanoparticles with Graphene Oxide as Effective Growth Inhibitors of Wound-Derived Bacteria.

Keeping wounds clean in small animals is a big challenge, which is why they often become infected, creating a risk of transmission to animal owners. Therefore, it is crucial to search for new biocompatible materials that have the potential to be used in smart wound dressings with both wound healing and bacteriostatic properties to prevent infection. In our previous work, we obtained innovative hyaluronate matrix-based bionanocomposites containing nanosilver and nanosilver/graphene oxide (Hyal/Ag and Hyal/Ag/GO). This study aimed to thoroughly examine the bacteriostatic properties of foils containing the previously developed bionanocomposites. The bacteriostatic activity was assessed in vitro on 88 Gram-positive (n = 51) and Gram-negative (n = 37) bacteria isolated from wounds of small animals and whose antimicrobial resistance patterns and resistance mechanisms were examined in an earlier study. Here, 69.32% of bacterial growth was inhibited by Hyal/Ag and 81.82% by Hyal/Ag/GO. The bionanocomposites appeared more effective against Gram-negative bacteria (growth inhibition of 75.68% and 89.19% by Hyal/Ag and Hyal/Ag/Go, respectively). The effectiveness of Hyal/Ag/GO against Gram-positive bacteria was also high (inhibition of 80.39% of strains), while Hyal/Ag inhibited the growth of 64.71% of Gram-positive bacteria. The effectiveness of Hyal/Ag and Hyal/Ag/Go varied depending on bacterial genus and species. Proteus (Gram-negative) and Enterococcus (Gram-positive) appeared to be the least susceptible to the bionanocomposites. Hyal/Ag most effectively inhibited the growth of non-pathogenic Gram-positive Sporosarcina luteola and Gram-negative Acinetobacter. Hyal/Ag/GO was most effective against Gram-positive Streptococcus and Gram-negative Moraxella osloensis. The Hyal/Ag/GO bionanocomposites proved to be very promising new antibacterial, biocompatible materials that could be used in the production of bioactive wound dressings.

Dual-Layer Nanoengineered Urinary Catheters for Enhanced Antimicrobial Efficacy and Reduced Cytotoxicity.

Catheter-associated urinary tract infection (CAUTI) is the most common healthcare-associated infection; however, current therapeutic strategies remain insufficient for standard clinical application. A novel urinary catheter featuring a dual-layer nanoengineering approach using zinc (Zn) and silver nanoparticles (AgNPs) is successfully fabricated. This design targets microbial resistance, minimizes cytotoxicity, and maintains long-term efficacy. The inner AgNPs layer provides immediate antibacterial effects against the UTI pathogens, while the outer porous Zn layer controls zero-order Ag release and generates reactive oxygen species, thus enhancing long-term bactericidal performance. Enhanced antibacterial properties of Zn/AgNPs-coated catheters are observed, resulting in 99.9% of E. coli and 99.7% of S. aureus reduction, respectively. The Zn/AgNPs-coated catheter significantly suppresses biofilm with sludge formation compared to AgNP-coated and uncoated catheters (all, p < 0.05). The Zn/AgNP-coated catheter in a rabbit model demonstrated a durable, effective barrier against bacterial colonization, maintaining antimicrobial properties during the catheter indwelling period with significantly reduced inflammation and epithelial disruption compared with AgNP and uncoated groups. This innovation has the potential to revolutionize the design of antimicrobial medical devices, particularly for applications requiring long-term implantation. Although further preclinical studies are required to verify its efficacy and safety, this strategy seems to be a promising approach to preventing CAUTI-related complications.

Fungal-mediated synthesis of silver nanoparticles: a novel strategy for plant disease management.

Various traditional management techniques are employed to control plant diseases caused by bacteria and fungi. However, due to their drawbacks and adverse environmental effects, there is a shift toward employing more eco-friendly methods that are less harmful to the environment and human health. The main aim of the study was to biosynthesize silver Nanoparticles (AgNPs) from Rhizoctonia solani and Cladosporium cladosporioides using a green approach and to test the antimycotic activity of these biosynthesized AgNPs against a variety of pathogenic fungi. The characterization of samples was done by using UV-visible spectroscopy, SEM (scanning electron microscopy), FTIR (fourier transmission infrared spectroscopy), and XRD (X-ray diffractometry). During the study, the presence of strong plasmon absorbance bands at 420 and 450 nm confirmed the AgNPs biosynthesis by the fungi Rhizoctonia solani and Cladosporium cladosporioides. The biosynthesized AgNPs were 80-100 nm in size, asymmetrical in shape and became spherical to sub-spherical when aggregated. Assessment of the antifungal activity of the silver nanoparticles against various plant pathogenic fungi was carried out by agar well diffusion assay. Different concentration of AgNPs, 5 mg/mL 10 mg/mL and 15 mg/mL were tested to know the inhibitory effect of fungal plant pathogens viz. Aspergillus flavus, Penicillium citrinum, Fusarium oxysporum, Fusarium metavorans, and Aspergillus aflatoxiformans. However, 15 mg/mL concentration of the AgNPs showed excellent inhibitory activity against all tested fungal pathogens. Thus, the obtained results clearly suggest that silver nanoparticles may have important applications in controlling various plant diseases caused by fungi.

Therapeutic potential of silver nanoparticles from Helianthemum lippii extract for mitigating cadmium-induced hepatotoxicity: liver function parameters, oxidative stress, and histopathology in wistar rats.

Introduction: This study explores the therapeutic potential of silver nanoparticles (Ag NPs) synthesized using a Helianthemum lippii extract in mitigating cadmium-induced hepatotoxicity in Wistar rats. Given the increasing environmental and health concerns associated with cadmium exposure, novel and eco-friendly therapeutic strategies are essential. Methods: Ag NPs were characterized using X-ray diffraction, UV-Vis spectrometry, and energy-dispersive X-ray spectroscopy with scanning electron microscopy, confirming their formation with a cubic crystal structure and particle sizes ranging from 4.81 to 12.84 nm. A sub-acute toxicity study of Ag NPs (2 mg/kg and 10 mg/kg) was conducted, showing no significant difference compared to untreated control rats (n = 3 animals/group). Subsequently, adult Wistar rats (n = 5/group) were divided into a control group and three experimental groups: Ag NPs alone, exposure to 50 mg/kg CdCl2 in drinking water for 35 days, and CdCl2 exposure followed by 0.1 mg/kg/day Ag NPs intraperitoneally for 15 days. Results: In the CdCl2-exposed group, there was a significant decrease in body weight and increases in alanine and aspartate transaminase levels (p < 0.05 vs. control), indicating hepatotoxicity. Additionally, antioxidant defenses were decreased, and malondialdehyde levels were elevated. Liver histology revealed portal fibrosis, inflammation, necrosis, sinusoid and hepatic vein dilation, and cytoplasmic vacuolations. Treatment with Ag NPs post-CdCl2 exposure mitigated several adverse effects on liver function and architecture and improved body weight. Discussion: This study demonstrates the efficacy of Ag NPs synthesized via a green method in reducing cadmium-induced liver damage. These findings support the potential of Ag NPs in therapeutic applications and highlight the importance of sustainable and eco-friendly nanoparticle synthesis methods. By addressing both toxicity concerns and therapeutic efficacy, this research aligns with the growing emphasis on environmentally conscious practices in scientific research and healthcare.

Protease-activated CendR peptides targeting tenascin-C: mitigating off-target tissue accumulation.

To achieve precision and selectivity, anticancer compounds and nanoparticles (NPs) can be targeted with affinity ligands that engage with malignancy-associated molecules in the blood vessels. While tumor-penetrating C-end Rule (CendR) peptides hold promise for precision tumor delivery, C-terminally exposed CendR peptides can accumulate undesirably in non-malignant tissues expressing neuropilin-1 (NRP-1), such as the lungs. One example of such promiscuous peptides is PL3 (sequence: AGRGRLVR), a peptide that engages with NRP-1 through its C-terminal CendR element, RLVR.Here, we report the development of PL3 derivatives that bind to NRP-1 only after proteolytic processing by urokinase-type plasminogen activator (uPA), while maintaining binding to the other receptor of the peptide, the C-domain of tenascin-C (TNC-C). Through a rational design approach and screening of a uPA-treated peptide-phage library (PL3 peptide followed by four random amino acids) on the recombinant NRP-1, derivatives of the PL3 peptide capable of binding to NRP-1 only post-uPA processing were successfully identified. In vitro cleavage, binding, and internalization assays, along with in vivo biodistribution studies in orthotopic glioblastoma-bearing mice, confirmed the efficacy of two novel peptides, PL3uCendR (AGRGRLVR↓SAGGSVA) and SKLG (AGRGRLVR↓SKLG), which exhibit uPA-dependent binding to NRP-1, reducing off-target binding to healthy NRP-1-expressing tissues. Our study not only unveils novel uPA-dependent TNC-C targeting CendR peptides but also introduces a broader paradigm and establishes a technology for screening proteolytically activated tumor-penetrating peptides.