Fabrication of PVA-Silver nanoparticle composite film for elimination of microbial contaminant from effluent

The effluent contains many harmful microbes which should be eliminated before it is discharged into a water body. Silver nanoparticles (AgNPs) being high-quality significance and have a great impact on this research field as it inhibits microbial proliferation and infection. Therefore, it may use for Bioremediation purposes, our laboratory is fascinated by the production of polymer matrix entrapment silver nanoparticles for in situ bio-remediation purposes. The AgNPs was prepared from sawdust by decoction method. The yellowish solution turns into dark brown colour indicating the formation of AgNPs. A sharp SPR (Surface Plasmon Resonance) band formation in UV-vis spectroscopy scan establishes the formation and stability of silver nanoparticles in an aqueous solution. SEM microphotograph indicated roughly spheroidal structure with (63±3) nm average diameters of newly synthesized AgNp. Polyvinyl alcohol (PVA) is eco-friendly and non-toxic to the environment was chosen for the preparation of polymeric matrix. The non-toxic concentration (1 ?g/mL) of AgNp was dispersed into PVA solution followed by cross-linked with maleic acid. PVA- maleic acid is cross-linked by the formation of an ester bond, whereas silver nanoparticles physically entrap into the cross-linked matrix. The silver nanoparticles were released from the matrix nearly after 10 min of swelling of the composite film. In a microbial assay using E. coli agar medium, PVA-AgNp composite film shows the significant killing of microorganisms. Microbial elimination is measured indirectly by pH measurement and dissolved oxygen concentration measurement of the effluent in situ against RO- water, taken as control. The dissolved oxygen concentration from RO water and effluent water was measured on Day “0” followed by treatment and incubation at the BOD chamber. The treatment with PVA-AgNp composite film reduced the BOD Level and increase dissolved oxygen level simultaneously increasing the quality of water.

Simarouba Glauca Bark Extract Mediated Synthesis And Characterisation Of Iron Oxide And Silver Nanoparticles And Their Antibacterial, Cytotoxic And Photocatalytic Activity

Objective: The objective of the present study is the synthesis of iron oxide and silver nanoparticles using Simarouba glauca aqueous bark extract, characterization of the synthesized nanoparticles and evaluation of their antimicrobial, photocatalytic activity and cytotoxicity. Methods: The iron oxide and silver nanoparticles were synthesized using Simarouba glauca aqueous bark extract and crystal structures of the nanoparticles were determined by UV-Visible spectroscopy, Transmission Electron Microscopy, Scanning Electron Microscopy, X-ray Diffraction and Fourier Transform Infrared Spectroscopy. The in vitro cytotoxicity of the silver nanoparticles was evaluated using Dalton’s lymphoma ascites cells. The antibacterial assay of the silver nanoparticles was conducted using agar well diffusion method. Results: The UV-Visible spectrum of iron oxide nanoparticle showed an absorption maximum at 280 nm and silver nanoparticles showed an absorption maximum at 436 nm. This is XRD pattern of iron oxide nanoparticles exhibited a characteristic peak at 26.85 is of maghemite the corresponding miller indices is (211) and the synthesized iron oxide nanoparticles are amorphous in nature. TEM image reveals the size of the synthesized iron oxide nanoparticles in the range of 26-30 nm and the size of silver nanoparticles is in the range of 120-140 nm. Green synthesized iron nanoparticles using Simarouba glauca bark extract effectively degraded methylene blue dye. Conclusion: This study showed that the synthesized iron oxide and silver nanoparticles using Simarouba glauca aqueous bark extract exhibited pronounced antibacterial, anticancer and photocatalytic activity and can be used in the textile industry and also as an external antiseptic in prevention and treatment of bacterial infections.

Anti-tumor activity of plant-mediated synthesis of silver nanoparticles: research advances / 国际药学研究杂志

The study of the anti-tumor drugs with effect of killing tumor cells, low toxicity and safety is important for cancer medicine. The silver nanoparticles(AgNP)synthesized by plant extracts have strong anti-tumor activity. The class of drugs is stable, with good curative effect and fewer side effects, which provide an important way for tumor therapy. In this paper, the recent anti-tumor studies of silver nanoparticles synthesized by active components extracted from different parts of plants are reviewed in order to provide theoretical basis for clinical antitumor applications.

Preparation of doxorubicin modified silver nanoparticle and its anti-tumor activity in vitro / 天津医药

Objective To design and synthesize a novel type of combined anti-tumor drug-doxorubicin modified silver nanoparticles(DOX-Ag NPs)with pH response,characterize its physical and chemical properties,and investigate its drug responsive release and anti-tumor activity in vitro.Methods DOX-Ag NPs were prepared by coupling silver nanoparticles (Ag NPs) with doxorubicin (DOX) via a LA-NHNH2linker. The structure of LA-NHN=DOX was confirmed by nuclear magnetic resonance(1H NMR)and high resolution mass spectrometry(HRMS).The particle size and micromorphology of the nanoparticles were detected by dynamic light scattering (DLS) and transmission electron microscopy (TEM), respectively. The optical properties of the nanoparticles were characterized by UV-vis absorption spectroscopy and fluorescence spectroscopy.The DOX release kinetics of DOX-Ag NPs under different pH conditions were examined by dialysis method combined with fluorescence spectroscopy. The in vitro anti-tumor effects of DOX-Ag NPs were evaluated by MTT assay. Results DOX-Ag NPs were spherical nanoparticles with a particle size of (40.4 ± 3.8) nm. DOX-Ag NPs could rapidly release DOX under weak acid condition.DOX-Ag NPs significantly inhibited the proliferation and cell viability of HepG2 cells in concentration dependent manner.When DOX concentration was 0.5-20 mg/L(Ag concentration was 0.45-18 mg/L), the cell survival rate was significantly lower in DOX-Ag NPs group than that of DOX group and Ag NPs group(P<0.05). Conclusion DOX-Ag NPs are a combined anti-tumor nano-drug with pH-responsive ability, which can release DOX rapidly in tumor tissues and play an anti-tumor effect through synergistic treatment with Ag NPs in vitro.

Cytotoxic Effect on Cancerous Cell Lines by Biologically Synthesized Silver Nanoparticles

The biosynthesis of nanoparticles has been proposed as an environmental friendly and cost effective alternative to chemical and physical methods. Silver nanoparticles are biologically synthesized and characterized were used in the study. The invitro cytotoxic effect of biologically synthesized silver nanoparticles against MCF-7 cancer cell lines were assessed. The cytotoxic effects of the silver nanoparticles could significantly inhibited MCF-7 cancer cell lines proliferation in a time and concentration-dependent manner by MTT assay. Acridine orange, ethidium bromide (AO/EB) dual staining, caspase-3 and DNA fragmentation assays were carried out using various concentrations of silver nanoparticles ranging from 1 to 100 μg/mL. At 100 μg/mL concentration, the silver nanoparticles exhibited significant cytotoxic effects and the apoptotic features were confirmed through caspase-3 activation and DNA fragmentation assays. Western blot analysis has revealed that nanoparticle was able to induce cytochrome c release from the mitochondria, which was initiated by the inhibition of Bcl-2 and activation of Bax. Thus, the results of the present study indicate that biologically synthesized silver nanoparticles might be used to treat breast cancer. The present studies suggest that these nanoparticles could be a new potential adjuvant chemotherapeutic and chemo preventive agent against cytotoxic cells. However, it necessitates clinical studies to ascertain their potential as anticancer agents.

Antimicrobial effects of biosynthesized silver nanoparticles produced by Actinomyces spp. based on their sizes and shapes

Aims: Actinomyces are dominant soil microflora with potent activity for production of several enzymes and metabolites. In order to increase their survival in the environment these bacteria detoxify the metal ions and consequently produce the nanoparticles. The present study was undertaken to isolate Actinomyces strains from soil samples and their evaluation for the production of silver nanoparticles with antimicrobial property. Methodology and results: Two hundred soil samples were collected and subjected to isolation and identification (based on16SrRNA gene sequencing) of silver nanoparticles producing Actinomyces. The silver nanoparticles produced by Actinomyces were confirmed by UV-visible spectral analysis, scanning electron microscope (SEM) and Inductively Coupled Plasma (ICP). Furthermore, antimicrobial property of silver nanoparticles was assessed against pathogenic microorganisms viz., Staphylococcus aureus (PTCC 1431), Acinetobacter baumannii (PTCC 19606), Bacillus cereus (PTCC 1816), Escherichia coli (PTCC 1397), Salmonella typhi (PTCC 1609), Pseudomonas aeruginosa (PTCC 1707), Aspergillus niger (PTCC 5010) and Candida albicans (PTCC 5072). Of 48 Actinomyces isolated, 26 strains could produce silver nanoparticles and three of which showed potent activity for production of silver nanoparticles. Molecular identification of these strains exhibited detection of Actinomyces amycolicicoccus subflavus, Streptomyces flavoviridis and Streptomyces lateritius. The results obtained from characterization of the biosynthesis silver nanoparticles illustrated that their shapes and sizes were spindle and spherical and 47-103 nm respectively. However, the antimicrobial effect of silver nanoparticles against the pathogenic microorganisms was varied. Yet S. typhi followed by P. aeruginosa, were more sensitive and A. baumannii was relatively less sensitive. In addition, spherical shape with small average size relatively showed more antimicrobial property. Conclusion, significance and impact of study: Soil Actinomyces could produce silver nanoparticles and these particles have antimicrobial effect. In addition, the antimicrobial effect of silver nanoparticles, not only because of their chemical property (such as formation of free radical) but also depended on their shapes and sizes.

Silver nanoparticle production by the fungus Fusarium oxysporum: nanoparticle characterisation and analysis of antifungal activity against pathogenic yeasts

The microbial synthesis of nanoparticles is a green chemistry approach that combines nanotechnology and microbial biotechnology. The aim of this study was to obtain silver nanoparticles (SNPs) using aqueous extract from the filamentous fungus Fusarium oxysporum as an alternative to chemical procedures and to evaluate its antifungal activity. SNPs production increased in a concentration-dependent way up to 1 mM silver nitrate until 30 days of reaction. Monodispersed and spherical SNPs were predominantly produced. After 60 days, it was possible to observe degenerated SNPs with in additional needle morphology. The SNPs showed a high antifungal activity against Candida and Cryptococcus , with minimum inhibitory concentration values ≤ 1.68 µg/mL for both genera. Morphological alterations of Cryptococcus neoformans treated with SNPs were observed such as disruption of the cell wall and cytoplasmic membrane and lost of the cytoplasm content. This work revealed that SNPs can be easily produced by F. oxysporum aqueous extracts and may be a feasible, low-cost, environmentally friendly method for generating stable and uniformly sized SNPs. Finally, we have demonstrated that these SNPs are active against pathogenic fungi, such as Candida and Cryptococcus .

Evaluation and comparison of anti-Candida effect of heat cure polymethylmethacrylate resin enforced with silver nanoparticles and conventional heat cure resins: An in vitro study.

Recent years have been dominated by research in nano science. Dentistry is no exception and there is increased research on nanoparticles in dentistry. Complete dentures increase the carriage of Candida in healthy patients, and the proliferation of C. albicans can be associated with denture-induced stomatitis. Purpose: To evaluate the anti-Candida effect of heat cure denture base resins reinforced with Ag° in the ratio of 4:1, 3:1, 2:1 (Groups B, C, and D, respectively) to the weight of denture base resins. Materials and Methods: Ag° were synthesized by chemical reduction method, incorporated into the polymer powder according to the ratio for each group, subjected to polymerization and microbial assay was calculated for the reference C. albicans strains by agar diffusion method for the incubation period of 24 h. Results: Group D showed multifold decrease in the colony-forming units. Conclusion: The antimicrobial effect of silver could be used vividly in the denture base for immunocompromised and geriatric patients.

Characterization and Determination of Silver Nanoparticle Using Single Particle -Inductively Coupled Plasma-Mass Spectrometry / 分析化学

Asingleparticle-inductivelycoupledplasmamassspectrometric(SP-ICP-MS)methodwas established to detect the size distribution and number concentrations of silver nanoparticle ( AgNPs) in dilute aqueous solution. The optimal dwell time was 3 ms to reduce possibility of two or more particles entering into detector simultaneously. An iterative algorithm was applied to distinguish AgNPs as outliers from baseline and dissolved metal ion signal if the measured intensity was beyond five time standard deviation of whole data. Size distribution and number concentration of three commercial silver nanoparticle dispersions ( nominal diameters of 30, 50, 100 nm) were determined using SP-ICP-MS. The result of SP-ICP-MS is accurately similar to the transmission electron microscopy ( TEM) , indicating that SP-ICP-MS is able to size silver nanoparticles. The particle size detection limit is 25 nm and the limit of number concentration is 8 × 104 particles/L in dilute solution. Tap water added with silver nanoparticle was tested to obtain a similar size distribution and number concentration. This method is simple, fast and highly sensitive, which can be used to investigate risk assessment of silver nanoparticle in aqueous environment and monitor silver nanoparticle in drinking water.

Biological Response of Muskmelon (Cucumis melo L.) to Magnetic Field and Silver Nanoparticles.

Aims: This experiment was done to study the responses of muskmelon (Cucumis melo L.) to magnetic field and silver nanoparticles combinations in comparison with commercial fertilizers in field conditions. Study Design: Experiment was conducted in a randomized complete block design with four replications. Place of Study: The present study was done at the Razavi Research and Technology Institute in Mashhad, Iran. Methodology: This experiment tested seven treatments based on a randomized complete block design in four replications. The treatments were as follows: AgM: Silver nanoparticles + magnetic field; HAgM: Humax commercial fertilizer + Silver nanoparticles + magnetic field; Humax: Humax commercial fertilizer; KAgM: Kemira commercial fertilizer + Silver nanoparticles + magnetic field; Kemira: Kemira commercial fertilizer; Librel: Librel commercial fertilizer, and Control. Results: Results indicated that treatments of silver nanoparticles with magnetic field (AgM) had the highest fruit yield (16.420 ton ha-1) followed by the Kemira fertilizer treatment (10.248 ton ha-1). Significantly, silver nanoparticles with magnetic field treatment (AgM) showed by 150% more fruit yield in comparison to the control. The highest fruit yield in second harvest was achieved in silver nanoparticles + magnetic field + Kemira commercial fertilizer (KAgM) and the lowest was found in the control and Librel treatments. Using AgM, KAgM and Librel treatments caused early ripening of fruit in muskmelon. AgM treatment indicated larger fruit size than control. Using silver nanoparticles + magnetic field (AgM) significantly increased content of fruit soluble solid (13.1%) related to control (9.8%) in first harvest. Conclusion: The treatment combining silver nanoparticles and magnetic field (AgM) most effectively improved early ripening of fruit, fruit and the quality of muskmelon fruit like soluble solid concentration compared to other treatments in firs harvest.

Biochemical and Nanotechnological Studies in Selected Seaweeds of Chennai Coast.

Three different seaweeds Gracilaria corticata J.Agardh ,Grateloupia lithophila Boergesen and Chaetomorpha antennina(Bory) kuetz used for the study were subjected for the estimation of carbohydrates, proteins, aminoacids, lipids and pigments such as chlorophyll a, chlorophyll b, carotenoid and phycobilins. They were also used for the nanoparticles synthesis and also checked for the blood glucose level changes by the oral administration of the seaweeds (0.5 g/day) to 6 mice for 20 days and with 3 mice as controls. The chaetomorpha, grateloupia and gracilaria estimation results showed 18.4%, 5.5%, 3.6% for carbohydrates, 15.8%, 30.5%, 23.7% for proteins, 4.9%, 22.94%, 11.04% for amino acids, 0.3%, 1.8%, 1.2% for lipids, 33.93, 1.35, 2.97 (mg/g fresh sample) for total chlorophyll, 0.2, 0.6, 5.49 (mg/g fresh sample) for carotenoid, 1.75, 2.1, 5.04 (μg/g fresh sample) for phycoerythrin respectively. They were also investigated for the extracellular biosynthesis of silver and gold nanoparticle and have achieved rapid formation of gold nanoparticles using Chaetomorpha antennina and Gracilaria corticata. It has been confirmed with the surface plasmon resonance.

Application of Silver Nanoparticles for the Control of Colletotrichum Species In Vitro and Pepper Anthracnose Disease in Field

Pepper anthracnose caused by Colletotrichum species is one of the most important limiting factors for pepper production in Korea, its management being strongly dependent on chemicals. The aim of this work was to evaluate the possibilities of using silver nanoparticles instead of commercial fungicides. In this study, we evaluated the effect of silver nanoparticles against pepper anthracnose under different culture conditions. Silver nanoparticles (WA-PR-WB13R) were applied at various concentrations to determine antifungal activities in vitro and in the field. The application of 100 ppm concentration of silver nanoparticles produced maximum inhibition of the growth of fungal hyphae as well as conidial germination in comparison to the control in vitro. In field trials, the inhibition of fungi was significantly high when silver nanoparticles were applied before disease outbreak on the plants. Scanning electron microscopy results indicated that the silver nanoparticles caused a detrimental effect on mycelial growth of Colletotrichum species.

In Vitro Antimicrobial Activities of NanoSilver-coated Gauze against Clinical Isolates / 대한임상미생물학회지

BACKGROUND: It is well-known that silver ions and silver compounds are broad-spectrum antimicrobial agents effective against gram-positive and gram-negative bacteria, and yeasts. Thus, silver ions, as an antibacterial agent, have been used in the components of materials used in medical devices or coatings. Recently, advances in nanotechnology have enabled manufacturers to develop silver particles of a nanometer size with a safer and more effective antimicrobial activity. So, we evaluate the antimicrobial activity of nanoSilver-coated gauze against clinical isolates. METHODS: Three kinds of nanoSilver-coated gauzes (100A, 800A, and 1,500A) were tested for antimicrobial activity by the disk diffusion method. The organisms tested included clinical isolates of nonfermentative gram-negative bacilli (143 isolates), aerobic gramnegative bacteria (188), aerobic gram-positive bacteria (397), anaerobic bacteria (46), and yeasts (161), and three reference ATCC strains. RESULTS: The susceptible rates to NanoSilver of nonfermentative gram-negative bacilli (NFB), aerobic gramnegative bacteria and aerobic gram-positive bacteria were 87%, 87% and 78%, respectively. Antimicrobial activity of NanoSilver against imipenem-resistant NFB, extended spectrum beta-lactamase (ESBL) producing Enterobacteriaceae, and methicillin-resistant Staphylcoccus aureus (MRSA) was similar to that against imipenem-sensitive NFB, ESBL non-producing Enterobacteriaceae, and methicillin-susceptible S. aureus. CONCLUSION: NanoSilver-coated gauze exhibits broad spectrum antimicrobial activities to a large number of gram-negative and gram-positive bacteria including imipenem-resistant NFB, ESBL producing Enterobacteriaceae, and MRSA.