Conjugated Silver Nanoparticles Research Articles

Preparation of a glassy carbon electrode modified with saffron conjugated silver nanoparticles for the sensitive and selective electroanalytical determination of amoxicillin in urine samples.

Determination of antibiotics is crucial in order to assess their potential impacts on human health and the environment. This study aimed to develop a modified glassy carbon electrode with saffron conjugated silver nanoparticles for the determination of amoxicillin antibiotic in urine samples. The modified electrode was prepared by electrodeposition of silver nanoparticles on the electrode surface, followed by deposition of amoxicillin on the surface. The electrochemical behavior of the modified electrode was studied by cyclic voltammetry and square wave voltammetry. The results showed that the modified electrode exhibited enhanced electrocatalytic activity toward the oxidation of amoxicillin. The calibration curve was linear in the concentration range from 1.273 × 10-4 g L-1 to 2.217 × 10-3 g L-1, with a high linear correlation coefficient of 0.9998. The detection limit was determined to be 4.199 × 10-5 g L-1. The precision of the sensor was adequate, with relative standard deviations of 4.3% and 4.0% for AMX concentrations of 9.199 × 10-5 g L-1 and 1.194 × 10-4 g L-1, respectively. The modified electrode was then applied to the determination of amoxicillin in urine samples. The method showed linearity over the amoxicillin concentration range from 0.00 to 2.00 × 10-4 g L-1, with a detection limit of 9.739 × 10-6 g L-1, indicating the potential of the modified electrode for the determination of amoxicillin in biological samples. Overall, the modified glassy carbon electrode with silver nanoparticles showed very promising results for the sensitive and selective determination of amoxicillin in urine samples.

Electrochemical immunoassay of antibodies using freshly prepared and aged conjugates of silver nanoparticles

In this work, silver nanoparticles (AgNPs) were conjugated with immunoglobulins G using a simple passive adsorption method and the composition and properties of freshly prepared (Ab@AgNPs) and aged (Ab@AgNP/Ag2SNPs) conjugates were investigated for the first time by transmission electron microscopy (TEM), energy dispersive X-ray spectroscopy (EDS), X-ray photoelectron spectroscopy (XPS) and voltammetry. It was found that the state of the AgNPs in the conjugates changed during storage. In the freshly prepared Ab@AgNPs conjugates, silver is present in the metallic state only, while the aged Ab@AgNP/Ag2SNPs conjugates are characterized by the presence of a metallic core of AgNPs coated with a “corona” of Ag2S. This affects the selection of voltammetric conditions for recording an analytical signal from the silver label in the conjugates. The Ab@AgNPs and Ab@AgNP/Ag2SNPs conjugates were successfully tested in the electrochemical immunoassay of dog immunoglobulins as a model. A solid-phase indirect non-competitive assay was performed using a 96-well ELISA plate. To record intense analytical signals from the silver conjugates by linear scan anodic stripping voltammetry (LSASV) on a carbon composite electrode (CCE), they were preliminarily dissolved in acidic solutions. In the case of the Ab@AgNPs conjugate, a nitric acid solution (1 mol L−1) was used to dissolve silver conjugates, while in the case of Ab@AgNP/Ag2SNPs, a 1:1 mixture of 1 mol L−1 CH3COOH and 1 mol L−1 HNO3 was used. The CH3COOH dissolved the Ag2S “corona”, and HNO3 dissolved the silver core of the Ab@AgNP/Ag2SNPs conjugate.This work opens up the possibility of the prolonged use of silver conjugates in electrochemical immunoassay, which can be used in commercial test systems for immunological studies as an alternative to conjugates labelled with enzyme labels.

Hemolytic Activity, Cytotoxicity, and Antimicrobial Effects of Silver Nanoparticles Conjugated with Lincomycin or Cefazolin.

The overuse of antibiotics has led to the emergence of resistant bacteria. A good alternative is silver nanoparticles, which have antibacterial activity against Gram-negative and Gram-positive bacteria, including multidrug-resistant strains. Their combination with already known antibiotics has a synergistic effect. In this work, we studied the synthesis of conjugates of silver nanoparticles with two antibiotics, lincomycin and cefazolin. Albumin and glutathione were used as spacer shells with functional groups. The physicochemical properties of the obtained conjugates, their cytotoxicity and synergism of antimicrobial activity were studied. The 50% antimicrobial activity of the obtained samples was shown, which allows them to be recommended for use as topical drug preparations.

NK-lysin antimicrobial peptide-functionalized nanoporous alumina membranes as biosensors for label-free bacterial endotoxin detection

We report an NK-lysin peptide-functionalized nanoporous anodized aluminum oxide (NAAO) based biosensor to detect bacterial endotoxin. Bovine NK-lysin-derived peptides show antimicrobial activity against bacterial pathogens, and bactericidal activity is primarily due to the membranolysis activity. Antimicrobial activity of NK-lysin NK2A was confirmed against a Gram-negative Mannheimia haemolytica and a Gram-positive Staphylococcus aureus. Electron microscopic examination showed the localization of NK2A conjugated silver nanoparticles, but not unconjugated silver nanoparticles used as control, to the bacterial outer membrane and cell wall. NK2A functionalized NAAO membranes were used in a previously developed four-electrode electrochemical configuration to detect the presence of Gram-negative bacterial lipopolysaccharides (LPS) and Gram-positive bacterial lipoteichoic acid (LTA) molecules. NK2A-functionalized NAAO biosensor could detect LPS with a detection limit of 10 ng/mL within an appreciable signal/noise ratio. Biosensors functionalized with a scrambled amino acid version of NK2A (Sc-NK2A) that lacks antimicrobial activity could not detect the presence of LPS. However, both NK2A and Sc-NK2A functionalized biosensors showed sensing signals with Gram-positive bacterial lipoteichoic acids. These results suggest that the specific binding of NK2A-LPS on the NAAO membrane surface is responsible for the observed biosensor signals. These findings suggest that NK2A-functionalized biosensors can be used for rapid and sensitive label-free LPS detection.

Conjugated silver nanoparticles as a diagnostic tool for circulating hydatid antigens

Cystic hydatid disease is one of the most significant worldwide zoonotic diseases. The causative agent is the larval stage of Echinococcus granulosus. The diagnosis of cystic echinococcosis by clinical symptoms and scanning alone is often difficult and confusing. The definite diagnosis needs sensitive and reliable serological tests. This study aimed to evaluate a nano silver-based enzyme linked immunosorbent assay (ELISA) in the detection of circulating hydatid antigen in human serum samples. The study included 66 human serum samples (36 hydatidosis confirmed cases, 15 cases infected with other parasites, and 15 normal subjects as negative control). The circulating protoscolices antigen was assayed by the nano-silver dot ELISA, nano-silver sandwich ELISA and the traditional methods (dot ELISA and sandwich ELISA). Our study revealed that the sensitivity and specificity of the nano-silver dot ELISA were 97.2% and 93.3%, respectively. The sensitivity and specificity of nano-silver sandwich ELISA were 94.4% and 96.7% respectively. The nano-silver-based ELISA showed higher sensitivity, specificity, positive predictive value, negative predictive value, and diagnostic accuracy than the traditional ELISA. In conclusion, the nano-silver-based ELISA can be proposed as a confirmatory test in the diagnosis of cystic echinococcosis.

Effect of Folic Acid Conjugated Silver Nanoparticles in Treatment of RA Like Adjuvant Arthritis in Rats

Objective: Nano medicine has become one of the promising research areas, opening new horizons in disease diagnosis and treatment. Recent years have witnessed a surge in the development of Nano medicine for combating rheumatoid arthritis (RA), the most common autoimmune arthritis. RA is characterized by progressive inflammation and persistent synovitis, leading to joint destruction, functional incapability, and ultimately disability. Although there has been a tremendous evolution in disease assessment and treatment, many patients still fail to attain remission. Therefore, developing new drugs that specifically target inflamed joints and simultaneously attenuate other possible damages to healthy tissues is indispensable. This study was done to evaluate the potential of folic acid conjugated silver nanoparticles (FA-AgNPs) as RA therapy. Methods: In the CFA-arthritic rat model, FA-AgNPs & methotrexate were administered for 8 consecutive weeks. Therapeutic efficacy was evaluated by measuring paw volume, erythrocyte sedimentation rate (ESR), C-reactive protein (CRP), tumor necrosis factor (TNF-α), and interleukin-6 (IL-6) levels. For safety concerns, complete blood picture (CBC), liver and renal function tests were evaluated. Joints histological assessment was also carried out. Results: FA-AgNPs significantly reduced paw volume, paw weight, ESR, CRP, RF, TNF-α, and IL-6 levels compared with arthritic non-treated rats, demonstrating good anti-inflammatory activity. Likewise, histology of tarsal joints depicted comparatively lesser inflammatory cellular infiltration and diminished cartilage erosions. Methotrexate displayed comparable results. In contrast to methotrexate, FA-AgNPs showed normal CBC & significantly improved liver and renal function tests. Conclusion: FA-AgNPs exhibited substantial anti-arthritic activity. This notable anti-arthritic potential of FA-AgNPs was as good as the current standard treatment of methotrexate (MTX) with higher biosafety.

Preparations Based on the Maleic Acid Copolymers Containing Silver Nanoparticles and Cations and Furan-2-Carboxylic Acid: Synthesis and Antituberculosis Activity

The complexes of silver ions with furan-2-carboxylic acid (Fur-COOH) and the conjugates of polymer-stabilized silver nanoparticles with silver cations and Fur-COOH are synthesized. The silver nanoparticles are studied by transmission electron microscopy (TEM), while the resulting conjugates—by UV–vis spectroscopy. All the objects obtained display prominent in vitro activity against the H37Rv strain of Mycobacterium tuberculosis. A synergistic effect of the silver components is revealed for the conjugates based on maleic acid-alt-N-vinylpyrrolidone containing nano- and cationic forms of silver, as well as Fur-COOH.

β-sitosterol conjugated silver nanoparticle-mediated amelioration of CCl4-induced liver injury in Swiss albino mice

ObjectiveDrug induced hepatocyte death is a major contributor to acute liver failure. We aimed to determine whether β-sitosterol conjugated silver nanoparticles (BSAgNPs) could ameliorate carbon tetrachloride (CCl4)-induced liver injury in Swiss albino mice. MethodsBiogenic silver nanoparticles were synthesized from β-sitosterol to produce β-sitosterol (BS) conjugated silver nanoparticles. Serum liver function assays in mice model with CCl4-induced liver injury revealed that alanine aminotransferase (ALT), aspartate aminotransferase (AST), alkaline phosphatase (ALP), bilirubin and cholesterol levels decreased markedly after treatment with β-sitosterol and BSAgNPs. In vivo liver enzymatic assays, including superoxide dismutase (SOD), catalase and reduced glutathione (GSH) were conducted to assess the antioxidant activity of the treatments. ResultsLiver tissue from BSAgNP treated mice displayed significantly elevated SOD activity (73.57 ± 1.48%) when compared to positive control group with silymarin treatment. Catalase activity decreased drastically in CCl4 treated mice (47.14 ± 1.08%), but increased with the administration of BSAgNPs (72.24 ± 2.25%). An increase in transforming growth factor β (TGF-β1) in liver tissue homogenate accompanied a reduction in nuclear factor erythroid-2-related factor 2 (Nrf2) in CCl4 treated mice. β-sitosterol and BSAgNPs mediated the reduction of TGF-β1. In the BSAgNPs treated mice, Nrf2 level was significantly elevated; however, no change was detected following β-sitosterol treatment. ConclusionOur findings reveal that β-sitosterol conjugated silver nanoparticles (BSAgNPs) may cause activation of the Nrf2 gene, through potential inhibition of TGF β1/Smad signaling. Antifibrotic effect of BSAgNPs may promote the lowering of chronic inflammation, oxidative stress and collagen deposition. Nanoparticle-mediated drug delivery of β-sitosterol may therefore have therapeutic promise against hepatic complications.

Acridine-2,4-Dinitrophenyl Hydrazone Conjugated Silver Nanoparticles as an Efficient Sensor for Quantification of Mercury in Tap Water

Excretion of heavy metals especially mercury (Hg2+) from the industries into the environment becomes a major global problem. In this context, mercury is a highly dangerous metal which poses serious impact on human health. In the present study, acridine- (ACR-) based silver nanoparticles (ACR-AgNPs) were prepared and employed as a nanosensor for effective detection and quantification of Hg2+ in tap water. Conjugation between ACR-based coating agent and silver was examined by UV-visible and FT-IR spectroscopy, while morphology and particle size were determined through atomic force microscopy (AFM), dynamic light scattering (DLS), and scanning electron microscopy (SEM). Furthermore, sensing behavior of nanosensor for metal ions was evaluated by mixing different metals such as Mn2+, Ni2+, Ba2+, Mg2+, Cr3+, Pb2+, Pd2+, Al3+, Sn2+, Fe2+, Co2+, Cu2+, Fe3+, Cd2+, and Hg2+with ACR-AgNPs. Among all the added metal ions, only Hg2+resulted in significant quenching in the absorption intensity of ACR-AgNPs. The limit of detection of the ACR-AgNP-based nanosensor was found to be 1.65 μM in a wide pH range (1-14). The proposed mercury sensor worked efficiently in the presence of other interfering agents such as other metal ions. Therefore, the synthesized ACR-AgNPs have proved to be an efficient and robust nanosensor for quantitative detection of Hg2+ in real sample analysis such as tap water. The proposed method does not require expensive instrumentation and trained manpower.

Studies on testicular ultrastructural and hormonal changes in type-2 diabetic rats treated with highly active antiretroviral therapy conjugated silver nanoparticles

AimThis study investigated the impact of highly active antiretroviral therapy (HAART) loaded silver nanoparticles (AgNPs) as HAART-AgNPs on the sperm count, viability, serum hormonal profile, insulin-like growth factor I (IGF-1), and testicular ultrastructure. MethodsThirty-six adult male Sprague-Dawley rats were allocated into diabetic and non-diabetic groups (n = 18). The rats in the diabetic group were induced experimental type 2 diabetes using fructose and streptozotocin (frt-STZ). Animals in both groups were subdivided into three groups each, A-C and DF (n = 6), and received distilled water, HAART, and HAART-AgNP, respectively. FindingsTreatment with HAART-AgNP displayed a significant increase (p < 0.05) in serum gonadotropin-releasing hormone (GnRH), follicle-stimulating hormone (FSH), luteinizing hormone (LH), and testicular IGF-1 in diabetic rats. Also, electron microscopy revealed ameliorated testicular ultrastructure upon administration of HAART-AgNP in diabetic rats that were previously marked with architectural and cellular alterations. In addition, treatment with HAART-AgNP significantly reduced (p < 0.05) the blood glucose levels of diabetic rats. In contrast, the treatment of non-diabetic rats with HAART caused a significant decrease (p < 0.05) in the sperm count, serum GnRH, and testicular IGF-1, however, this treatment induced ultrastructural changes and a significant increase (p < 0.05) in serum testosterone levels in diabetic and non-diabetic rats. SignificanceThis study has demonstrated the beneficial impact of HAART-AgNP on the hypothalamic-pituitary-gonadal axis, IGF-1, and testicular architecture in male frt-STZ induced diabetic rats. This nanoconjugate could be a potential nano-drug candidate to cater for testicular dysfunction and metabolic derangements while managing HIV-infected male individuals.

Characterization and Rate of Killing of Conjugated Silver Nanoparticles Against Selected Clinical Bacterial Isolates

The menace of drug resistance, bioavailability and drug delivery to the target sites has motivated researchers to search for new antimicrobial agents from medicinal plants and subsequently use them for the biosynthesis of silver nanoparticles for effective killing of bacteria challenging to kill using crude extracts. The biosynthesis of silver nanoparticles was done using aqueous extract (AQE) of E&lt;i&gt;uphorbia heterophylla&lt;/i&gt;, while characterization and the killing rate of conjugated silver nanoparticles (CA&lt;sub&gt;g&lt;/sub&gt;NP&lt;sub&gt;s&lt;/sub&gt;) were carried out using standard methods. The maximum wavelength obtained for CA&lt;sub&gt;g&lt;/sub&gt;NP&lt;sub&gt;s&lt;/sub&gt; was 410.33 nm, while the size distribution was 237.8 d.nm. The Fourier Transform Infra-Red result showed O-H (3308.94 cm&lt;sup&gt;-1&lt;/sup&gt;), which is responsible for stabilising and reducing silver ions, while the Transmission Electron Microscopy revealed the presence of monodispersed spherical shapes CA&lt;sub&gt;g&lt;/sub&gt;NP&lt;sub&gt;s&lt;/sub&gt;. The Energy Dispersive Spectroscopy confirmed the presence of silver. There were reductions in the clinical bacterial isolates exposed to CA&lt;sub&gt;g&lt;/sub&gt;NP&lt;sub&gt;s&lt;/sub&gt; as the exposure time increased. &lt;i&gt;Escherichia coli&lt;/i&gt; was killed between 6-7 h while&lt;i&gt; Salmonella typhimurium&lt;/i&gt; was killed at the seven has the value of 0.00 log&lt;sub&gt;10&lt;/sub&gt; CFU/ml was recorded respectively. However, there were increments in the populations of clinical bacterial isolates in control as the time of exposure increased. Therefore, the study suggests that the CA&lt;sub&gt;g&lt;/sub&gt;NP&lt;sub&gt;s&lt;/sub&gt; exhibit intense antimicrobial activity and the potential to be developed as an alternative agent to treat bacterial infections, curb multidrug-resistant bacterial infection, and promote speedy drug delivery to the target sites.

Electrochemical Immunoassay of Antibodies Using Freshly Prepared and Aged Conjugates of Silver Nanoparticles

Electrochemical Immunoassay of Antibodies Using Freshly Prepared and Aged Conjugates of Silver Nanoparticles

Neurotherapeutic effects of prodigiosin conjugated with silver-nanoparticles in rats exposed to cadmium chloride-induced neurotoxicity

Prodigiosin is a red pigment produced by Serratia marcescens strain. Bacterial prodigiosin and its synthetic derivatives are efficacious antioxidants and proapoptotic agents. This study illustrates a new approach for use of prodigiosin conjugated silver nanoparticles (PG-AgNP2) against cadmium chloride (CdCl2) induced neurotoxicity in rats. Rats were (ip) injected with Cd (6.5 mg/kg) for 7 days with or without PG-AgNP2 (3 mg/kg). The concentration of Cd, DA, NE, 5-HT, amino acids, NO, MDA, SOD, GSH, catalase, TNF-α, IL-6, Bax, Bcl2 and Caspase-3. The Cd-intoxicated group showed a significant increase in Cd concentration in brain tissue, in addition, to an increase in MDA and NO and a decrease in the content of neurotransmitters (DA, NE, and 5-HT), inhibitory amino acids, and level of all studied antioxidant enzymes. PG-AgNP2 treatment, significantly reduced Cd-induced brain tissue injury as indicated by increased antioxidant molecules, neurotransmitters (DA, NE, and 5-HT), and inhibitory amino acids accompanied by lower oxidative stress indices (MDA and NO) and excitatory amino acids in brain tissue. PG-AgNP2 decreased inflammatory mediators including pro-inflammatory cytokines and prevented the development of apoptosis in the brain tissue. Our findings suggest that PG-AgNP2 can act as a therapeutic agent against neuronal impairments associated with Cd exposure.

Synthesis and characterization of triazole stabilized silver nanoparticles as colorimetric probe for mercury

This study reports the synthesis and characterization of triazole stabilized silver nanoparticles and their investigation as a colorimetric sensor for Hg2+ in tap water. Benzotriazole conjugated silver nanoparticles (BT-AgNPs) were synthesized using the chemical reduction method. Techniques such as UV–visible, Zetasizer, FTIR, SEM, and AFM were used for the characterization of the nanoparticles. The nanoparticles were highly monodispersed and revealed a mean size of 40–50 nm. Further, they were found highly stable at elevated temperatures and over a wide range of electrolyte concentrations and pH. The nanoparticles were then investigated as a colorimetric sensor for Hg2+. The addition of mercury significantly suppressed nanoparticles' absorption intensity and the color change from yellow to colorless. They were found highly selective towards Hg2+in the presence of other interfering metal ions. The binding ratio between the nanoparticles and Hg2+ was found to be 1:1 as determined by the jobs plot experiment. The nanoparticles demonstrated sensitivity towards a wide concentration of Hg2+ with a limit of detection of 0.33 µM. The synthesized nanoparticles were finally used as a sensing probe for Hg2+ detection in water. The limit of detection of the current sensor is lower than most of the reported methods. These findings reveal the triazole stabilized nanoparticles as an easy, selective, and sensitive sensing probe for Hg2+.

Antibacterial and anti bio film activities of novel antibiotic conjugated silver nanoparticles

This study reports an eco-friendly, cost effective and biological synthesis of meropenem antibiotic conjugated silver nanoparticles (mer-AgNPs). The synthesized (mer-AgNPs) nanoparticles were characterized using UV–Visible spectrophotometer, transmission electron Microscope, Fourier-transform infrared spectroscopy (FT-IR), TEM. mer-AgNPs have increased antibacterial activity against both Gram-positive and Gram–negative bacteria (Staphylococcus aureus (MTCC 96), Listeria monocytogens (MTCC 657), Vibrio vulnificus (MTCC 1145), Shigella flexneri (MTCC 1457), Escherichia coli (MTCC 1687), and Salmonlla typhimurium (MTCC 3224). In addition, mer-AgNPs are highly effective against biofilm producers compared to the antibiotic alone. The photocatalytic activity shows good results in Congo red with AgNPs.

Synthesis and Photonics Applications of Afzelechin Conjugated Silver Nanoparticles

The silver nanoparticles were synthesized, functionalized with afzelechin and characterized using UV-Visible spectroscopy. A difference of 20 nm was observed in surface plasmon resonance of bare and functionalized silver nanoparticles which indicates afzelechin conjugation with silver nanoparticles. The atomic force microscopy (AFM) technique was used for the determination of the size and morphology of synthesized silver nanoparticles. The afzelechin conjugated silver nanoparticles were spherical and their sizes ranged from 3 to 10 nm with an average size of 8 nm while the bare silver nanoparticles were also spherical and their sizes ranged from 3 to 10 nm with an average size of 6 nm. The average sizes were also calculated by fitting their UV-Visible absorption spectra. Fitting is based on the Mie and Mie Gans models, which deduced that afzelechin conjugated silver nanoparticles were 96.5% spherical and 3.5% spheroidal with an average size of 5 nm while bare silver nanoparticles were 100% spherical with an average size of 4 nm. Both the fitting model as well as the AFM results showed a difference of 3 nm between the sizes of afzelechin conjugated silver nanoparticles while 2 nm differences was observed for bare silver nanoparticles. The band gap energy of afzelechin conjugated silver nanoparticles and bare silver nanoparticles were calculated via Tauc’s equation and were found to be 5.1 eV and 5.4 eV, respectively. A difference of 0.3 eV was observed in band gap energies of afzelechin conjugated silver nanoparticles and bare silver nanoparticles.

Synergistic effect of plant extract coupled silver nanoparticles in various therapeutic applications- present insights and bottlenecks

The phytocomponent conjugated silver nanoparticles (AgNPs) have been extensively explored for various therapeutic applications such as antimicrobial, antioxidant, anticancer, anti-inflammatory, antidiabetic and anticoagulant effects. The bio-conjugation of Ag-based nanomaterial with plant extracts reduces their toxicity to biological systems and enhances their therapeutic effectiveness. The diversity of phytochemicals or capping agents provided by the plant extracts and the small size and large surface area of AgNPs permits maximum adsorption of these capping agents onto their surfaces that further promote the therapeutic performance of phytoconjugated AgNPs in various biomedical applications. The mechanistic action involved in antimicrobial and anticancer functions of AgNPs is mainly dependent on the induction of reactive oxygen species (ROS) resulting in cellular apoptosis and necrosis. This review summarizes the recent studies of various plant extract assisted synthesis of AgNPs, potential biomedical applications with the possible mechanism of action and major shortcomings affecting their therapeutic efficacy.

Silver nanoparticles with epigallocatechingallate and zinc sulphate significantly inhibits avian influenza A virus H9N2

Avian influenza (AI) has become a disease of great importance for human and animal health. Beside adverse side effects, there is resistance mutation for about all the conventional drugs that target viral proteins. This study aimed to evaluate antiviral activity of silver nanoparticles combined with epigallocatechingallate (EGCG-AgNPs) and co-administered with zinc sulphate (Zn+2) as alternative treatment strategy to control AI H9N2. EGCG conjugated silver nanoparticles (EGCG-AgNPs) were synthesized. Virus propagation was performed using embryonated Specific-Pathogen-Free (SPF) hen's eggs. Viral EID50 titers were determined before and after treatments. The antiviral activity was determined as Log virucidal reduction. A commercial tetrazolium MTS assay kit was used to determine cytotoxicity. Results showed that 50 μM EGCG was the most significant concentration reduced the logEID50/mL of AI H9N2. Co-treatment with zinc sulphate (1.3 mg/mL) increased the EGCG antiviral effect. The most effective antiviral activity was obtained when combined EGCG-AgNPs with zinc sulphate with the greatest virucidal log reduction. No cytotoxic effect in Vero cells was observed among all of these forms at concentrations of interest used in this study. In conclusion, the topical application of EGCG-AgNPs/ZnSO4 demands additional antiviral strategies against H9N2 AI. This combination may prevent virus transmission, inhibit virus replication within neighboring cells and inhibit microbial resistance by making microbial adaptability very difficult.

Synthesis, Characterization and In Vitro Antibacterial Evaluation of Pyrenacantha grandiflora Conjugated Silver Nanoparticles.

In the present study, silver nanoparticles (AgNPs) were synthesized using both the chemical and biological methods and conjugated with Pyrenacantha grandiflora extracts. These were then characterized and evaluated for antimicrobial activities against multi-drug resistant pathogens, such as methicillin-resistant Staphylococcus aureus (MRSA), Klebsiella pneumonia, and Escherichia coli. Nanoparticles were analyzed with UV-visible spectrophotometer, transmission electron microscopy (TEM), and energy dispersive X-ray analysis (EDX). Silver nanoparticles, P. grandiflora extracts, and the conjugates were also analyzed with Fourier transform infrared spectroscopy (FTIR). As a result, quasi-sphere-shaped AgNPs with sizes ranging from 5 to 33 nm and spherically shaped AgNPs with sizes ranging from 3 to 25 nm were formed from chemical and biological synthesis, respectively. A well diffusion assay showed that the activity of silver nanoparticles was most improved with acetone extract against all tested bacteria with diameters in the range of 19–24 mm. The lowest MIC value of 0.0063 mg/mL against MRSA was observed when biologically synthesized AgNPs were conjugated with acetone and water extracts. Chemically synthesized silver nanoparticles showed the lowest MIC value of 0.0063 mg/mL against E. coli when conjugated with acetone and methanol extracts. This study indicates that silver nanoparticles conjugated with P. gandiflora tubers extracts exhibit strong antibacterial activities against multi-drug resistant bacterial pathogens. Therefore, biosynthesized conjugates could be utilized as antimicrobial agents for effective disease management due to the synergistic antibacterial activity that was observed.

Detection of antibiofilm formation by sliver nanoparticles created by tetracycline antibiotic

Silver conjugated Tetracycline, was created and characterized by ultraviolet visible spectrophotometry (UV-vis), Fourier transform infrared (FT-IR), X-Ray Diffraction Patterns (XRD). Using antibacterial assays, the effects of tetracycline alone and drugs-conjugated with silver nanoparticles were tested against Gram-ve Pseudomonas aeruginosa isolates by well diffusion assay. The UV-vis spectra of silver-drug Nano conjugates showed a characteristic surface Plasmon resonance band in the range of 400–450 nm. FTIR analysis demonstrated the involvement of Hydroxyl groups in both drugs in the stabilization of silver nanoparticles. (XRD) showed that they cubic structure of silver and, antibacterial assays showed that biosynthesis silver nanoparticle conjugation enhanced antibacterial potential of Tetracycline compared with drug alone.