Biofunctionalized Silver Nanoparticles Research Articles

Preparation of biofunctionalized silver nanoparticles using Clerodendrum glandulosum leaf extract for evaluation of its antibacterial efficacy

Preparation of biofunctionalized silver nanoparticles using Clerodendrum glandulosum leaf extract for evaluation of its antibacterial efficacy

Biofunctionalized silver nanoparticles synthesized from Passiflora vitifolia leaf extract and evaluation of its antimicrobial, antioxidant and anticancer activities

The present study describes the synthesis of silver nanoparticles (AgNPs) using Passiflora vitifolia (P. vitifolia) leaf extract as reducing and capping agent. Characterization of the synthesized AgNPs was done with the help of UV-Vis. spectroscopy, atomic force microscopy (AFM), fourier transform infrared microscopy (FTIR), zeta potential, thermo gravimetric analysis (TGA), scanning electron microscopy (SEM), transmission electron microscopy (TEM) and X-ray diffraction (XRD) analysis. The formation of AgNPs was confirmed by the presence of an absorption peak at 388 nm in UV-Vis. spectrum, poly-dispersed nature and size range from 39.06 to 58.24 nm was displayed by AFM and different functional groups were recognized by FTIR analysis. AgNPs showed stability at − 20.3 mV through zeta potential. SEM and TEM analysis revealed that AgNPs were spherical, poly-dispersed particles with minimum size of 11.61 nm and XRD analysis showed face-centered cubic and crystalline nature. The AgNPs demonstrated a notable antimicrobial efficacy against pathogenic microorganisms and showed a substantial antioxidant activity against DPPH free radicals. Further, AgNPs conveyed potent anticancer activity against murine macrophage (RAW-264.7) cell line with a significant IC50 value of 57.63 µg/mL. The synthesized AgNPs signified good antimicrobial, antioxidant and anticancer activity; hence it has the possibility to be used in various biomedical applications after successful clinical trials.

Antibacterial studies of bio-functionalized carbon decorated silver nanoparticles (AgNPs)

In the present report, Lemon juice (bio-extract) extract was efficaciously used for the synthesis of bio-functionalized silver nanoparticles (Ag-1, Ag-2 & Ag-3 NPs) and decorated with carbon material obtained from mustard oil. The morphology, size, crystal structure, formation and interaction were studied by means of innumerable analytical methods including scanning electron microscopy (SEM), transmission electron microscopy (TEM), high-resolution transmission electron microscopy (HR-TEM), X-ray diffraction (XRD), and Fourier-transform infrared (FT-IR) spectroscopy. The XRD results approve the formation of AgNPs with face-centered cubic (fcc) lattice. The XRD results also exhibit some unassigned peaks which might be due to the presence of bio-organic materials on the surface of AgNPs. The bands observed from the IR spectra showing the involvement of biomolecules onto the surface of silver nanoparticles. Mostly citric acid plays a major role in bio-reduction, capping agent, and stabilization of silver ions. We attained maximal inhibition zone (2.10 ​± ​0.05 and 2.03 ​± ​0.027) counter to gram-negative bacteria K. pneumoniae and P. bacilli with Ag-3 respectively, but lowest inhibition zone (1.27 ​± ​0.22) contrary to S. aureus as a gram-positive bacteria with Ag-2.

Anti-cancer & anti-metastasis properties of bioorganic-capped silver nanoparticles fabricated from Juniperus chinensis extract against lung cancer cells

The current study evaluated the anti-cancer properties of bio-functionalized silver nanoparticles fabricated by Juniperus chinensis leaf extracts. The nanoparticles were characterized by scanning electron microscopy, transmission electron microscopy, UV–visible spectroscopy, Fourier transform infrared spectroscopy, X-ray diffraction, dynamic light scattering, Zeta potential and X-ray spectroscopy. Further, this study elucidated the cellular and molecular mechanisms of nanoparticles for anti-proliferative and apoptotic effects on human lung cancer cells (A549) and compared them with commercial drug cisplatin. The size of the spherical nanoparticle was 12.96 nm with negative zeta potential. Up-regulation of caspase 3,9 and p53, Annexin V-FITC/PI, DAPI staining, and ROS production indicated the remarkable apoptotic effect of AgNPs compared to cisplatin. Moreover, down-regulation of MMP2/MMP9 scratch and matrigel assays revealed anti-metastatic properties of AgNPs. Cell cycle analysis and downregulation of cyclin D1 indicated cancer cell cessation in the G0/G1 phase. Overall, the results revealed that the green-synthetized AgNPs had anti-metastasis and anti-proliferation effects on lung cancer cells in comparison to cisplatin with lower side effects on the normal cell line.

Synergistic effects of combinatorial chitosan and polyphenol biomolecules on enhanced antibacterial activity of biofunctionalized silver nanoparticles

The present study reports the synergistic antibacterial activity of biosynthesized silver nanoparticles (AgNPs) with the aid of a combination of chitosan and seaweed-derived polyphenols as a green synthetic route. Under optimum synthesis conditions, the rapid color change from yellowish to dark brown and UV–visible absorption peak at 425 confirmed the initial formation of AgNPs. DLS, TEM, XRD, and EDX analyses revealed the spherical shape of pure biogenic AgNPs with a mean diameter size of 12 nm ± 1.5 nm, and a face-centered cubic crystal structure, respectively. FTIR and TGA results indicated the significant contribution of chitosan and polyphenol components into silver ions bioreduction and thermal stability of freshly formed AgNPs. Long-term colloidal stability of AgNPs was obtained after 6-month storage at room temperature. The bio-prepared AgNPs possessed a negative surface charge with a zeta potential value of − 27 mV. In contrast to naked chemical silver nanoparticles, the green Ag nanosamples demonstrated the distinct synergistic antibacterial in vitro toward all selected human pathogens presumably due to the presence of high content of biomolecules on their surface. The results show that synergy between chitosan and polyphenol results in the enhancement of bactericidal properties of biogenic AgNPs. We also highlighted the underlying mechanism involved in AgNPs formation based on nucleophile–electrophile interaction.

Biofunctionalization of mycosynthesized silver nanoparticles on selected drug resistant human pathogens

Nanotechnology has been a boon to mankind as its significance paved the way for several applications in therapeutics. Silver nanoparticles are powerful nano-weapons in the destruction of multiple drug resistant pathogens. The process of biosynthesis of silver nanoparticles is a simple, cost effective and eco-friendly approach. In the present study, aqueous extract of edible mushroom Pleurotus florida is used for the synthesis of biofunctionalized silver nanoparticles. The biosynthesis parameters such as pH, silver nitrate concentration, silver nitrate to mushroom extract ratio, temperature, incubation condition and duration of synthesis were optimized to maximize the yield of silver nanoparticles. Its formation was confirmed using UV–visible spectroscopy and characterized by Scanning Electron Microscopy (SEM), Energy Dispersive x-ray Spectroscopy (EDX) and Fourier Transform Infrared Spectroscopy (FTIR). FTIR spectrum revealed the possible biomolecules responsible for capping and efficient stabilization of the nanoparticles. Further, biological evaluation of these silver nanoparticles showed potential antimicrobial action against seven bacterial and two fungal pathogens by agar well diffusion method. The microbicidal property of the biosynthesized nanosilver showed significant positive correlations associated with the dose- dependent effect and thus it might have high potential medical applications in controlling drug- resistant infections.

A Comparative Study for Detection of Melamine in Solution by Interference Sensing Using Functionalized Silver Nanoparticles

In this research an attempt has been made for instantaneous sensing of melamine, a potential milk adulterant, at room temperature with the help of bio-functionalized silver nanoparticles. The bio-functionalized nanoparticles were made using leaf extracts of Parthenium hysterophorous and Calotropis procera. Also these methods were compared with the nanoparticles that were functionalized with sulfanillic acid. Colorimetric change was the basis of sensing the melamine using these bio-functionalized silver nanoparticles. Melamine upto a limit of 0.1 ppm was detected by the particles prepared using Parthenium hysterophorous leaf extract at room temperature. UV-visible spectroscopy (200–800 nm range) was used to detect the changes in the absorbance of silver nanoparticles with the addition of melamine in different concentrations. DLS studies were carried out to confirm the presence of nanoparticles and to study their surface morphology during sensing. Comparative study showed that Parthenium hysterophorous (noxious hysterophorous) leaf extract was far better and accurate in detecting melamine and was as accurate as the silver nanoparticles functionalized with sulfanillic acid. This can be attributed to the fact that Parthenium hysterophorous leaf extract contains caffeic acid which worked as a reducing agent and also as the bio functionalized chemical. Thus, this method can be further used as a rapid detection of melamine. In addition, this method can be converted into prototype for detection of melamine in industries.

Emphasized Mechanistic Antimicrobial Study of Biofunctionalized Silver Nanoparticles on Model Proteus mirabilis.

Antimicrobial study of biofunctionalized silver nanoparticles has been done with the emphasis on its mechanism on both gram positive and negative bacteria. The biofunctionalized silver nanoparticles are employed considering their importance in green chemistry with respect to easy synthesis, usefulness, and economic synthetic procedure involved. The stability of these nanoparticles was determined by zeta potential analyzer. The probable mechanism of antibacterial activity was performed on Proteus mirabilis by field emission scanning electron microscopy (FESEM) and energy dispersive spectroscopy (EDAX) study which does not show the presence of silver. The free radicals generated by silver nanoparticles were responsible for lethal antibacterial activity by rupturing the cell surface which causes improper nutrient and signal supply. Free radical scavenging efficacy of silver nanoparticles was confirmed by 1,1-Diphenyl-2-picrylhydrazyl (DPPH) method. AgNP enhanced the membrane leakage of reducing sugars by destroying the proteins existing on the cell wall. These nanoparticles are found to be toxic against human pathogens and are highly effective on Staphylococcus aureus. The effect of silver nanoparticles is concentration dependent and independent of the type of strains used.

Anti-cancer and anti-oxidant properties of ethanolic leaf extract of Thymus vulgaris and its bio-functionalized silver nanoparticles.

This study highlights the anti-oxidant and anti-cancer activities of bio-functionalized Thymus vulgaris silver nanoparticles (TVAgNPs) and bioactive compounds were compared using the human breast cancer T47D cell line. The aqueous ethanolic extract of T. vulgaris evaluated for chemical composition using the gas chromatography-mass spectrometer (GC-MS) analysis. The prepared TVAgNPs were determined by means of UV-Vis spectroscopy, FTIR spectroscopy, zeta potential, scanning electron microscopy, transmission electron microscopy, and energy-dispersed spectroscopy analysis. The T. vulgaris extract and TVAgNPs were studied for their in vitro anti-oxidant property by 2, 2-diphenyl, 1-picryl hydrazyl (DPPH) assay. Microscopic observations indicated spherical shaped and monodispersed nanoparticles and the average size of the nanoparticles was about 30nm. Regarding the elemental composition profile of the TVAgNPs, the highest signal of silver (89.30%) was detected followed by other elements. An absorption peak was registered at 440nm according to surface plasmon resonance (SPR) of the TVAgNPs in solution. A zeta potential of fabricated nanoparticles was approximately -12.6mV, indicating higher stability of the bio-functionalized TVAgNPs. The T. vulgaris extract and synthesized TVAgNPs were evaluated for their anti-cancer activity using 3-(4,5-dimethylthiazol-2-yl)-2,5-diphenyl-tetrazolium bromide (MTT) assay and Annexin V double staining with propidium iodide (PI) flow cytometric analysis toward T47D cells. The cytotoxicity properties of the bio-functionalized T. vulgaris AgNPs revealed that the sensitivity of T47D human breast cancer cells is high compared with T. vulgaris extract. The Annexin V/PI staining indicated that the fabricated TVAgNPs shows increased apoptosis in T47D cells as compared to untreated cells. Besides, the anti-oxidant activity of the TVAgNPs clarified a higher anti-radical-scavenging activity compared to Thymus vulgaris extract. Our data show that the potential biological activities of the bioactive constituents of T. vulgaris can be enhanced through bio-functionalized T. vulgaris AgNPs due to the bioorganic compounds that exist in the extract.

Antimicrobial Properties of Biofunctionalized Silver Nanoparticles on Clinical Isolates of Streptococcus mutans and Its Serotypes.

(1) Background: Streptococcus mutans (S. mutans) is the principal pathogen involved in the formation of dental caries. Other systemic diseases have also been associated with specific S. mutans serotypes (c, e, f, and k). Silver nanoparticles (SNP) have been demonstrated to have good antibacterial effects against S. mutans; therefore, limited studies have evaluated the antimicrobial activity of biofunctionalized SNP on S. mutans serotypes. The purpose of this work was to prepare and characterize coated SNP using two different organic components and to evaluate the antimicrobial activity of SNP in clinical isolates of S. mutans strains and serotypes; (2) Methods: SNP with bovine serum albumin (BSA) or chitosan (CS) coatings were prepared and the physical, chemical and microbiological properties of SNP were evaluated; (3) Results: Both types of coated SNP showed antimicrobial activity against S. mutans bacteria and serotypes. Better inhibition was associated with smaller particles and BSA coatings; however, no significant differences were found between the different serotypes, indicating a similar sensitivity to the coated SNP; (4) Conclusion: This study concludes that BSA and CS coated SNP had good antimicrobial activity against S. mutans strains and the four serotypes, and this study suggest the widespread use of SNP as an antimicrobial agent for the inhibition of S. mutans bacteria.

Antibacterial and biological properties of biofunctionalized nanocomposites on titanium for implant application.

Titanium implants possessing excellent antibacterial activity are highly desirable for the prevention of implant-associated infections. In this study, we demonstrate a simple one-step, water-based procedure for the fabrication of biofunctionalized nanocomposites on titanium for implant application. The formation of biofunctionalized silver nanoparticles with varied biomolecule templates is confirmed by Fourier-transform infrared spectroscopic, contact angle, field-emission scanning electron microscopy, and inductively coupled plasma atomic emission spectrometry analysis. Antibacterial properties of the specimens were determined by challenging them against Staphylococcus aureus The Ag-incorporated titanium shows excellent antibacterial ability against planktonic bacteria in the suspension and ability to prevent bacterial adhesion. The specimens with optimized biomolecule/silver ratio promote osteoblast differentiation. These biofunctionalized silver nanoparticles-doped titanium specimens, with improved antibacterial activity while maintaining healthy osteoblast cellular activity, have promising application in orthopedics, dentistry, and other biomedical devices.

An investigation on cytotoxic effect of bioactive AgNPs synthesized using Cassia fistula flower extract on breast cancer cell MCF-7

A single step protocol to produce biofunctionalized silver nanoparticles (AgNPs) using the aqueous extract of Cassia fistula flower as “natural factory” was investigated. The reaction between silver ions and aqueous flower extract after the bioreduction process has resulted in the formation of reddish brown color colloidal solution. XRD pattern showed the face centered cubic crystalline structure of AgNPs and exhibited spherical morphology as characterized by FE-SEM. FTIR studies identified different functional groups involved in effective capping of AgNPs. The zeta potential affirmed the phytoreduced AgNPs possess good stability and the size of the particle was measured by DLS. The synthesized AgNPs displayed effective cytotoxic potential against MCF7 and the inhibitory concentration (IC50) was recorded at 7.19μg/mL. The apoptotic effects of the AgNPs were also confirmed by AO/EB staining. The investigation presents preliminary evidence that biosynthesized AgNPs can be used in the development of novel anticancer drugs.

Biofunctionalized silver nanoparticles as a novel colorimetric probe for melamine detection in raw milk.

Nanoparticles have emerged as a promising analytical tool for monitoring food adulteration and safety. In the present study, silver nanoparticles (AgNPs) were synthesized using leaves' extract of Jatropha gossypifolia. AgNPs revealed a characteristic surface plasmon resonance (SPR) peak at 419nm and have spherical and grain shape with size range between 18 and 30nm. A selective and rapid method of melamine detection in raw milk was developed with the use of these biofunctionalized AgNPs. The color change, deviation in SPR spectra, and change in the absorption ratio (A500 /A419 ) of AgNPs occurred after an AgNPs-melamine interaction. The detection limit for melamine up to 2μM (252ppb) was attained with this method, which is quite lower than safety level recommendations of regulatory bodies demonstrating sensitivity of the method. Dynamicx light scattering and transmission electron microscopy analyses exhibited an increase in hydrodynamic diameter and size of AgNPs after melamine interaction. Melamine sensing by AgNPs was investigated by different physicochemical and thermal analyses.

Potential anticancer properties of bioactive compounds of Gymnema sylvestre and its biofunctionalized silver nanoparticles.

BackgroundGymnema sylvestre is an ethno-pharmacologically important medicinal plant used in many polyherbal formulations for its potential health benefits. Silver nanoparticles (SNPs) were biofunctionalized using aqueous leaf extracts of G. sylvestre. The anticancer properties of the bioactive compounds and the biofunctionalized SNPs were compared using the HT29 human adenoma colon cancer cell line.MethodsThe preliminary phytochemical screening for bioactive compounds from aqueous extracts revealed the presence of alkaloids, triterpenes, flavonoids, steroids, and saponins. Biofunctionalized SNPs were synthesized using silver nitrate and characterized by ultraviolet–visible spectroscopy, scanning electron microscopy, energy-dispersive X-ray analysis, Fourier transform infrared spectroscopy, and X-ray diffraction for size and shape. The characterized biofunctionalized G. sylvestre were tested for its in vitro anticancer activity against HT29 human colon adenocarcinoma cells.ResultsThe biofunctionlized G. sylvestre SNPs showed the surface plasmon resonance band at 430 nm. The scanning electron microscopy images showed the presence of spherical nanoparticles of various sizes, which were further determined using the Scherrer equation. In vitro cytotoxic activity of the biofunctionalized green-synthesized SNPs (GSNPs) indicated that the sensitivity of HT29 human colon adenocarcinoma cells for cytotoxic drugs is higher than that of Vero cell line for the same cytotoxic agents and also higher than the bioactive compound of the aqueous extract.ConclusionOur results show that the anticancer properties of the bioactive compounds of G. sylvestre can be enhanced through biofunctionalizing the SNPs using the bioactive compounds present in the plant extract without compromising their medicinal properties.

Inhibition of restriction endonucleases by biofunctionalized silver nanoparticles: An in vitro study

Ecofriendly synthesis of metal nanoparticles and their unique properties hold promise for innovative therapeutic applications. In the present study, rapid, novel, low cost method for synthesis of silver nanoparticles (AgNPs) using aqueous leaves extract of medicinal plant Euphorbia heterophylla (E. heterophylla) is reported. AgNPs synthesized by plant extract exhibited absorption peak at 422nm in UV–vis spectroscopy. Transmission electron microscopy micrographs revealed presence of AgNPs with average size of 13nm with grain and triangular shapes. Fourier Transform Infrared Spectroscopy analysis revealed role of leaves metabolites as reducing and capping agent in synthesis of AgNPs. X ray diffraction pattern and selected area electron diffraction study confirmed crystalline nature of AgNPs. Inhibition of DNA cutting activity of restriction endonucleases (EcoRI, HindIII and BamHI) by biofunctionalized AgNPs in agarose gel electrophoresis is first time reported in the present study. This potential of AgNPs can be useful for enhancing effectiveness of phage therapy by acting as synergistic cocktail with bacteriophages to kill bacteria via inhibition of their restriction endonucleases.

Bio-functionalized silver nanoparticles for selective colorimetric sensing of toxic metal ions and antimicrobial studies

Hibiscus Sabdariffa (Gongura) plant extracts (leaves (HL) and stem (HS)) were used for the first time in the green synthesis of bio-functionalized silver nanoparticles (AgNPs). The bio-functionality of AgNPs has been successfully utilized for selective colorimetric sensing of potentially health and environmentally hazardous Hg2+, Cd2+ and Pb2+ metal ions at ppm level in aqueous solution. Importantly, clearly distinguishable colour for all three metal ions was observed. The influence of extract preparation condition and pH were also explored on the formation of AgNPs. Both selectivity and sensitivity differed for AgNPs synthesized from different parts of the plant. Direct correlation between the stability of green synthesized AgNPs at different pH and its antibacterial effects has been established. The selective colorimetric sensing of toxic metal ions and antimicrobial effect of green synthesized AgNPs demonstrated the multifunctional applications of green nanotechnology.

Photo-Irradiated Biosynthesis of Silver Nanoparticles Using Edible MushroomPleurotus floridaand Their Antibacterial Activity Studies

This is a report on photo-irradiated extracellular synthesis of silver nanoparticles using the aqueous extract of edible oyster mushroom (Pleurotus florida) as a reducing agent. The appearance, size, and shape of the silver nanoparticles are understood by UV-visible spectroscopy, field emission scanning electron microscopy, transmission electron microscopy, and atomic force microscopy. The X-ray diffraction studies, energy dispersive X-ray analysis indicate that particles are crystalline in nature. Fourier transform infrared spectroscopy analysis revealed that the nanoparticles are covered with biomoieties on their surface. As can be seen from our studies, the biofunctionalized silver nanoparticles thus produced have shown admirable antimicrobial effects, and the synthetic procedure involved is eco-friendly and simple, and hence high range production of the same can be considered for using them in many pharmaceutical applications.

Microwave-Assisted Rapid Extracellular Biosynthesis of Silver Nanoparticles Using Carom Seed (Trachyspermum copticum) Extract and in Vitro Studies

Microwave-assisted rapid extracellular biosynthesis of silver nanoparticles was carried out by using carom seed (Trachyspermum copticum) extract as the reducing agent. The reaction mixture containing AgNO3 and carom seed extract when exposed to microwave irradiation resulted in reducing silver ions to bio-functionalized silver nanoparticles of size 6- 50 nm. The AgNP were characterized by UV-vis spectroscopy (UV-vis), X-ray diffraction (XRD), energy dispersive X-ray analysis (EDAX), field emission scanning electron microscopy (FESEM), transmission electron microscopy (TEM) and atomic force microscopy (AFM). Themogravimetric analysis (TGA) and fourier transform infrared spectroscopy (FTIR) are used to understand the possible mechanism of biosynthesis. In this study, we have also investigated the antimicrobial and antioxidant activities of bio-functionalized AgNP. The antibacterial activity is investigated by measuring the zone of inhibition and antioxidant study is done using 1,1-diphenyl-2-picryl hydrazyl (DPPH) method.

Microwave-assisted rapid extracellular synthesis of stable bio-functionalized silver nanoparticles from guava (Psidium guajava) leaf extract

Our research interest centers on microwave-assisted rapid extracellular synthesis of bio-functionalized silver nanoparticles of 26 ± 5 nm from guava (Psidium guajava) leaf extract with control over dimension and composition. The reaction occurs very rapidly as the formation of spherical nanoparticles almost completed within 90 s. The probable pathway of the biosynthesis is suggested. Appearance, crystalline nature, size and shape of nanoparticles are understood by UV–vis (UV–vis spectroscopy), FTIR (fourier transform infrared spectroscopy), XRD (X-ray diffraction), FESEM (field emission scanning electron microscopy) and TEM (transmission electron microscopy) techniques. Microwave-assisted route is selected for the synthesis of silver nanoparticles to carry out the reaction fast, suppress the enzymatic action and to keep the process environmentally clean and green.

Control of Colloid Surface Chemistry through Matrix Confinement: Facile Preparation of Stable Antibody Functionalized Silver Nanoparticles

Here we describe a simple yet efficient gel-matrix-assisted preparation method that improves synthetic control over the interface between inorganic nanomaterials and biopolymers and yields stable biofunctionalized silver nanoparticles. Covalent functionalization of the noble metal surface is aided by the confinement of polyethylene glycol acetic acid functionalized silver nanoparticles in thin slabs of a 1% agarose gel. The gel-confined nanoparticles can be transferred between reaction and washing media simply by immersing the gel slab in the solution of interest. The agarose matrix retains nanoparticles but is swiftly penetrated by the antibodies of interest. The antibodies are covalently anchored to the nanoparticles using conventional cross-linking strategies, and the resulting antibody functionalized nanoparticles are recovered from the gel through electroelution. We demonstrate the efficacy of this nanoparticle functionalization approach by labeling specific receptors on cellular surfaces with functionalized silver nanoparticles that are stable under physiological conditions.