Gold Silver Nanoparticles Research Articles

<i>Cocculus hirsutus</i> Leaf Assisted Green Synthesis of Ag-Au Bimetallic Nanoparticles and their Antioxidant Properties

Bimetallic nanoparticles (BMNPs) of silver and gold are synthesized by eco- friendly green chemical procedure using leaf extract of Cocculus hirsutus. Under the experimental condition most individual silver nanoparticles (AgNPs) and gold nanoparticles (AuNPs) are spherical whereas silver-gold bimetallic nanoparticles (Ag-Au BMNPs) found cloudy and lost their individual shape. Ag-Au BMNPs formed by the co-reduction of Au(III) and Ag(I) ions in aqueous leaves extract solution where the extract act as both reducing and capping agent. NPs were characterized with the help of UV-Vis absorption spectroscopy, high resolution transmission electron microscopy (HRTEM), X-ray diffraction (XRD) analysis. UV-Vis spectroscopy exhibit surface plasmon absorption maxima at 435 and 540 nm for AgNPs and AuNPs respectively whereas surface plasmon resonance (SPR) maxima for Au-Ag bimetallic appeared in between the peaks corresponding to pure silver and gold at the same reaction conditions. X-ray diffraction analysis confirmed that crystalline nanoparticles (NPs) are face centered cubic structure. The synthesized bimetallic nanocomposites show stronger scavenging ability, around 67% and 75% on hydroxyl radical and superoxide radicals at the concentration of 400 µg/ml respectively, compared to the mono metallic AgNPs and AuNPs, indicating stronger antioxidant properties of Ag-Au BMNPs.

Tuning Electrocatalytic Activity of Gold Silver Nanoparticles on Reduced Graphene Oxide for Oxygen Reduction Reaction

Gold-silver (AuAg) nanoparticles were deposited on reduced graphene oxide (rGO), with Au wt% varying from 34.6 to 46.2 and Ag wt% ranging from 31.7 to 35.3. Three AuAg/rGO samples were characterized by inductively coupled plasma optical emission spectroscopy, transmission and scanning electron microscopy with energy-dispersive X-ray spectroscopy, and X-ray diffraction analysis. Subsequently, AuAg/rGO materials were studied using the rotating disk electrode as electrocatalysts for oxygen reduction reaction (ORR) for potential application in alkaline fuel cells. AuAg/rGO-3 (with ca. 34.6 wt% Au and 35.3 wt% Ag) showed the most promising performance, with high ORR activity and good stability, as evidenced by the highest current density (−4.45 mA cm−2 at 0.5 V), the lowest Tafel slope (103 mV dec−1), and the highest number of electrons exchanged (4.1).

One-step synthesis and stabilization of Au, Ag and Au-Ag nanoparticles with an ion-exchange polymer contained amide and carboxylic acid functional groups

The synthesis and characterization of ion exchange polymer poly(4-acryloylaminobenzoic acid) (poly(4-AABA)), which contains amide and carboxylic acid functional groups on each repeating unit are reported. The polymer was used as reducing and stabilizing agent in the synthesis of gold nanoparticles, silver nanoparticles, and gold-silver nanoparticles at room temperature and 75 °C. The poly(4-AABA)-stabilized metallic nanoparticles were characterized by ultraviolet-visible spectroscopy, transmission electron microscopy, X-ray diffraction, and infrared spectroscopy. It was found that the amide group of the repeating unit of poly(4-AABA) confers the ability to reduce gold and silver ions by transferring the free electrons from the N atom. UV-Vis results showed that the process of reduction of the metallic ions by poly(4-AABA) at room temperature occurs slowly, and the obtention of the nanoparticles take place after several days. On increasing the temperature to 75 °C, the reduction rate increases considerably, and the formation of nanoparticles occurs over a few minutes. Conformational arrangement of poly(4-AABA) play an important role in controlling the size and shape of the nanoparticles. The composition of the Au-Ag nanoparticles strongly depends on the reaction temperature, changing from an Au-rich alloy when the temperature is 25 °C to an Ag-rich alloy at 75 °C. The poly(4-AABA) stabilizing to the nanoparticles in aqueous solution through the electro-steric stabilization mechanism, since through the carboxylic acid groups it interacts electrostatically with the surface of the particles and due to the long length of the polymeric chains, the poly(4-AABA) also envelops to particles controlling their growth and preventing agglomeration. Probable mechanism for formation of colloidal metallic nanoparticles in aqueous solution of poly(4-AABA) is proposed is discussed.

Thy-AuNP-AgNP Hybrid Systems for Colorimetric Determination of Copper (II) Ions Using UV-Vis Spectroscopy and Smartphone-Based Detection.

A colorimetric probe based on a hybrid sensing system of gold nanoparticles (AuNPs), silver nanoparticles (AgNPs), and thymine (Thy) was developed for easy and rapid detection of copper (II) ions (Cu2+) in solution. The underlying principle of this probe was the Cu2+-triggered aggregation of the nanoparticle components. Color change of the sensing solution (from red to purple) was clearly observed with naked eyes. The experimental parameters, including pH and concentration of tris buffer, thymine concentration and AgNP dilution ratios, were investigated and optimized. Once optimized, the limits of detection were found to be 1, 0.09 and 0.03 ppm for naked eyes, smartphone application and UV-vis spectrophotometer, respectively. Furthermore, determination of Cu2+ was accomplished within 15 min under ambient conditions. For quantitative analysis, the linearity of detection was observed through ranges of 0.09–0.5 and 0.03–0.5 ppm using smartphone application and UV-vis spectrophotometer, respectively, conforming to the World Health Organization guideline for detection of copper at concentrations < 2 ppm in water. This developed hybrid colorimetric probe exhibited preferential selectivity toward Cu2+, even when assessed in the presence of other metal ions (Al3+, Ca2+, Pb2+, Mn2+, Mg2+, Zn2+, Fe3+, Ni2+, Co2+, Hg2+ and Cd2+). The developed procedure was also successfully applied to quantification of Cu2+ in real water samples. The recovery and relative standard deviation (RSD) values from real water sample analysis were in the ranges of 70.14–103.59 and 3.21–17.63%, respectively. Our findings demonstrated a successful development and implementation of the Thy-AuNP-AgNP hybrid sensing system for rapid, simple and portable Cu2+ detection in water samples using a spectrophotometer or a smartphone-based device.

Synthesis of N-myristoyltaurine stabilized gold and silver nanoparticles: Assessment of their catalytic activity, antimicrobial effectiveness and toxicity in zebrafish

In this paper, the application of silver nanoparticles (AgNPs) and gold nanoparticles (AuNPs) synthesized using a biomimetic lipid, N-myristoyltaurine (N14T) was evaluated in common fields. The catalytic effectiveness of AgNPs and AuNPs was studied in the popular nanocatalyst reaction, nitroaromatic reduction, and dye degradation. Both NPs display catalytic activity in the nitroaromatic compound and organic dyes reduction reaction involving sodium borohydride and the rate constant is estimated as 10−3 s−1. Strikingly, the reaction initiation time (t0) and completion time (tc) differ significantly between AgNPs and AuNPs. Analyzing the reaction kinetic profile revealed that the reaction carried out with AuNPs showed a shorter t0 and tc, suggesting a better catalyst than AgNPs. In addition, the efficiency of the NPs was examined in Gram-positive bacteria (Staphylococcus aureus, Bacillus subtilis) and Gram-negative bacteria (Escherichia coli, Pseudomonas aeruginosa). In difference to the catalytic study, AuNPs display poor antibacterial activity. Whereas AgNPs kill the tested bacteria at 250 μM via disturbing bacterial membrane integrity and produce excess reactive oxygen species. The toxicology study carried out with zebrafish animal model reveals that both AgNPs and AuNPs are non-toxic. The findings suggest that each nanomaterial possesses unique physicochemical properties irrespective of stabilization with the same molecules.

Adsorption of Ag/Au nanoparticles by ordered macro-microporous ZIF-67, and their synergistic catalysis application

Silver nanoparticles (AgNPs) and gold nanoparticles (AuNPs) are universally used in diverse fields, but the use and treatment of various commodities will adversely affect the human health. Therefore, the recovery and immobilization of AgNPs and AuNPs from wastewater has important economic and social benefits. The ordered macro-microporous ZIF-67 single crystal (SOM-ZIF-67) was prepared by double solvent-assisted strategy. It was used as an adsorbent to remove precious metal pollutants, AuNPs and AgNPs. Under the optimal experimental conditions, the adsorption process of nanoparticles on SOM-ZIF-67 conformed to the pseudo-second-order kinetics. The theoretical maximum adsorption capacity of SOM-ZIF-67 towards AgNPs and AuNPs was 1250 mg g−1 and 2000 mg g−1, respectively. Through some characterization methods, it can be inferred that the adsorption mechanism might include ion-dipole interaction, metal-ligand interaction, and hydrogen bond, chelation and ion exchange between AgNPs/AuNPs and nitrogen and oxygen atom, and reduction etc. Furthermore, the interpenetrating macropores and micropores of SOM-ZIF-67 further promoting the adsorption capacity. Meanwhile, after the adsorption, the composite material (SOM-ZIF-67@AgNPs or SOM-ZIF-67@AuNPs) was developed as a new kind of heterogeneous catalyst that had good catalytic activity and cycle catalytic performance for 4-nitrophenol in the presence of NaBH4. At last, the adsorbent and catalyst could be regenerated. Simultaneously recycling of precious noble metal was also possible. Thus, the prepared SOM-ZIF-67 was a potential green adsorbent for the removal and recovery of precious metal nanoparticles. The secondary utilization as an effective catalyst would elaborate the sustainability of the method.

Phytofabrication of gold and bimetallic gold-silver nanoparticles using water extract of wheatgrass (Triticum aestivum), their characterization and comparative assessment of antibacterial potential

In the present study, gold (AuNPs) and gold-silver bimetallic nanoparticles (Au-Ag BMNPs) were fabricated by using water extract of leaves of Triticum aestivum - a crop plant, and their bactericidal potency was checked against selected pathogenic bacterial strains. The phytofabricated AuNPs and BMNPs were analyzed for their physical attributes using UV–Visible and Fourier transformed infrared spectroscopy, Dynamic light scattering, High-resolution transmission electron microscopy, Energy-dispersive X-ray spectroscopy. HRTEM analysis revealed that both kinds of NPs were highly crystalline in nature and of spherical and oval-shaped. AuNPs size was found in the range of 5-40 nm, whereas BMNPs showed their size in the range of 5-30 nm. HRTEM results were corroborated by DLS results which revealed the average hydrodynamic diameter of AuNPs and BMNPs in the range of 29.08 and 26.56 nm, respectively. UV-visible spectroscopy showed high-intensity single spectral peaks at 540 and 480 nm for AuNPs and BMNPs, respectively. FTIR analysis demonstrated that protein, flavanones, hydroxyl, carboxylate groups, and reducing sugars were responsible for reducing and capping of both NPs. Bactericidal efficiency of synthesized NPs was evaluated using agar-well diffusion and XTT-colorimetric assays against K. pneumoniae, S. typhimurium, E. aerogenes, E. coli, M. luteus, S. aureus, S. mutans and S. epidermidis. K. pneumonia and S. typhimurium were found to be the most sensitive bacteria towards BMNPs-mediated (MIC: 400 µg/ml) and AuNPs-mediated toxicity (MIC: 800 µg/ml). It was observed that BMNPs generally possessed more powerful bactericidal effect against all bacterial strains in comparison to AuNPs. MIC and MBC values were observed in the concentration range of 400 µg/ml-1.5 mg /ml for different bacterial strains. Furthermore, it was demonstrated that phytosynthesized AuNPs have their own bactericidal effect, but at higher concentrations (&gt;100 µg/ml), and bactericidal effect of BMNPs was due to the synergistic effect of both Ag and Au ions, which was also observed to be concentration-dependent.

Entropy generation analysis on EMHD peristaltic propulsion of blood-mediated gold-silver nanoparticles: application to fatal diseases

Metal-based nanoparticles play a vital role in diagnoses and treatment of critical ailments like cancer and infectious illness. In view of this, the current study deals with the mathematical modeling and simulation of electro-magneto-nanofluid (considered as suspension of silver/gold with blood) flow through peristaltic mechanism in an asymmetric channel with the effects of viscous dissipation, thermal radiation, slip and convective boundary conditions. The governing equations have been solved analytically under the assumptions of low Reynolds number and long wavelength. The influence of some sundry parameters on velocity, temperature, heat transfer coefficient, streamlines and shear stress have been represented graphically. It is observed from the results that, the temperature and velocity of gold-based nanofluid is more effective than silver-based nanofluid. The trends of velocity profiles are different near the walls with enhancement of electroosmosis parameter. The temperature of silver-based nanofluid increases in core part of the channel and the total entropy generation increases with the stronger magnetic field.

Influence of elemental composition on structural, thermal and hydration behavior of gold-silver bimetallic nanoparticles.

In this study, molecular dynamics simulations (MDs) have been employed to explore the influence of elemental composition on the structural, thermal, and hydration behavior of the core-shell gold-silver bimetallic nanoparticles with three different concentrations Au135Ag114, Au87Ag162, and Au55Ag194. The pure gold and silver metal nanoparticles have also been studied for the sake of comparison. The calculated cohesive and formation energy values reveal the enhancement in the stability of gold-silver bimetallic nanoparticles with the increase in the concentration of gold. The specific heat capacity value of the bimetallic gold-silver nanoparticles has been found to increase linearly with the concentration of silver. This suggests that the specific heat capacity value of the gold-silver bimetallic nanoparticles may be improved by raising their silver concentration. The enhancement of specific heat capacity value with respect to the concentration of silver may be attributed to the enhanced phonon density. There is no significant difference in the computed hydration shell and water residence time of the gold-silver bimetallic nanoparticles with respect to their mixing ratio. The obtained stable structure, tunable specific heat capacity values, and the predicted hydration properties of the gold-silver bimetallic nanoparticles may be harnessed for their technological and biological applications.

Comparative study of one pot synthesis of PEGylated gold and silver nanoparticles for imaging and radiosensitization of oral cancers

Head and neck squamous cell carcinomas (HNSCCs) pose strong therapeutic challenges especially oral cancers, due to proximity of functionally vital anatomic regions. Radiotherapy is an important and non-invasive treatment arm for oral cancers. The therapeutic effect of nanoparticles depends on size and type of material. In this study, we aim to synthesize one pot PEGylated gold nanoparticles (Au PEG NPs) and silver nanoparticles (Ag PEG NPs) and evaluate their toxicity and radiosensitization effect in oral cancer KB cell line. CT contrast capacity was measured in a phantom model and compared with clinically used imaging agent. PEGylated Au NPs and Ag NPs were synthesized using PEG 600 as the reducing and stabilizing agent. The surface charge of a well dispersed colloid was +20 mV and −18mV for Au PEG NPs and Ag PEG NPs respectively. Electron microscopy showed their near-spherical morphology. The hydrodynamic diameter for both metallic NPs was ∼50±5 nm due to PEG layer and water molecules absorption. Raman shift of around 20 cm−1 was observed when Au PEG NPs and Ag PEG NPs were coated with PEG. 1H NMR spectroscopy showed extended involvement of –OH in synthesis. The nano architecture was imaged using advanced electron microscopy along with crystal structure. The radiosensitization effect on KB cell line was highest at 4 Gy at dosage of 0.36 μg/ml Au PEG NPs and 0.23 μg/ml Ag PEG NPs. Confocal imaging of Hoechst-stained nuclei demonstrated apoptosis in a dose-dependent manner. Au PEG NPs exhibit better CT contrast enhancement ability than clinically used contrast agents and Ag PEG NPs. This study reveals the Au PEG NPs show higher radiosensitization effect compared to the Ag PEG NPs in KB cell line, Au PEG performed better than Ag PEG NPs and clinically used contrast agent Omnipaque due to high atomic number. Therefore, the Au PEG NPs could be a potential candidate as an enhanced radiosensitizer and CT imaging agent against oral cancers.

Comparative study of biogenically synthesized silver and gold nanoparticles of Acacia auriculiformis leaves and their efficacy against Alzheimer's and Parkinson's disease

The present article reports the biogenic synthesis of silver nanoparticles (AgNPs) and gold nanoparticles (AuNPs) from the extract of Acacia auriculiformis (AA) leaves using biogenic approach. Several spectral and morphological studies namely UV–vis, Fourier transform infrared (FT-IR), tunneling electron microscopy along with selected area electron diffraction (TEM/SAED), scanning electron microscopy along with energy dispersive X-ray (SEM-EDX) and X-ray diffraction (XRD) were carried out which ascertains the successful formation of silver nanoparticles (AgNPs) and gold nanoparticles (AuNPs) starting from Silver nitrate and Chloroauric acid respectively. On the basis of TEM/SAED and SEM-EDX, AgNPs were found to be more regular with smaller particle size and hence they were selected for biological studies. Thermal techniques like thermo gravimetric analysis (TGA) and differential thermal analysis (DTA) were also performed to study the comparative thermal stability of AgNPs and AuNPs where AgNPs were found to be thermally more stable. Several biophysical techniques including Thioflavin T assay, ANS assay, Rayleigh scattering method and turbidity assay were also performed. These assays confirm that AgNPs possess better inhibitory property. Moreover, antioxidant activity of AgNPs was also carried out using 2,2-diphenyl-1-picrylhydrazyl (DPPH) and AgNPs were found to be good antioxidant.

GMT8 aptamer conjugated PEGylated Ag@Au core-shell nanoparticles as a novel radiosensitizer for targeted radiotherapy of glioma

Radiotherapy is one of the main treatment modalities for glioma, but the therapeutic efficacy is often limited by the radioresistance of tumor cells. The radiosensitization effects of silver nanoparticles (AgNPs) and gold nanoparticles (AuNPs) on tumors have been confirmed by previous studies. To enhance the specific killing effect of irradiation on tumor cells, targeted modification of radiosensitizers is urgently needed. Herein, we developed polyethylene glycol (PEG)-coated Ag@Au core-shell nanoparticles (PSGNPs) modified with GMT8 aptamer (GSGNPs) and evaluated their radiosensitization effects on glioma cells through in vivo and in vitro experiments. Transmission electron microscope image showed that the prepared PSGNPs had a spherical core-shell structure with an average size of 11 nm. The ultraviolet-visible absorption spectra and Fourier transform infrared spectra displayed that GMT8 was successfully conjugated to PSGNPs. The results of dark-field imaging revealed that the targeting ability of GSGNPs to U87 glioma cells was much better than that to normal human microvascular endothelial cells. Additionally, it was also found that the endocytic pathways of GSGNPs mainly involved clathrin-mediated endocytosis and macropinocytosis. The sensitization enhancement ratio of GSGNPs was calculated to be 1.62, which was higher than that of PSGNPs. In vivo imaging results showed that GSGNPs exhibited good tumor targeting and retention capabilities, and the fluorescence intensity ratio of Cy5-GSGNPs to Cy5-PSGNPs reached a peak at 4 h after injection. More importantly, the median survival time of mice bearing U87 glioma was significantly prolonged after intravenous administration of GSGNPs combined with radiotherapy. This work demonstrated that GSGNPs could be used as an effective nano-radiosensitizer for targeted radiotherapy of glioma.

Green synthesis of plasmonic nanoparticles using Sargassum ilicifolium and application in photocatalytic degradation of cationic dyes

In the present work, a green synthetic method for the preparation of extremely stable silver nanoparticles (AgNPs) and gold nanoparticles (AuNPs) using Sargassum ilicifolium has been demonstrated. Thus produced nanoparticles were characterized by UV–Visible (UV–Vis) spectroscopy, Fourier Transform InfraRed spectroscopy (FT-IR), Energy Dispersive X-ray spectroscopy (EDX), X-Ray Diffraction (XRD), Transmission Electron Microscopy (TEM), Dynamic Light Scattering (DLS) and Zeta potential analyses. The average size of Ag and Au NPs was 27.9 and 9.36 nm respectively from TEM, which was further substantiated by XRD data. Zeta potential values of −42.2 mV and −28.3 mV for Ag and Au NPs respectively suggested that the nanoparticles were negatively charged and highly stable. AgNPs showed desirable bactericidal activity towards Enterobacter species, Pseudomonas aeruginosa, Escherichia coli, Staphylococcus aureus and Proteus species. The photocatalytic behaviour of AgNPs was studied to degrade malachite green (MG) and methylene blue (MB) in aqueous medium. In MG, 82.9% degradation was achieved in 180 min of light exposure and the pseudo first order rate constant was 7.2 × 10−3 min−1. In MB, almost 100% of the dye was degraded in the same period and the pseudo first order rate constant calculated was 7.5 × 10−3 min−1. The bio-derived AgNPs are hence promising materials for treating effluent from dyeing industries and water purification.

Simple and rapid biogenic synthesis of colloidal silver and gold nanoparticles using Aegle marmelos fruit for SERS detection of DNA

In the present communication potential of Aegle Marmelos extract is demonstrated as reducing and stabilizing agent for the eco-friendly synthesis of silver nanoparticles (SNPs) and gold nanoparticles (GNPs). The characteristic surface plasmon resonance peak for SNPs was observed at 425 nm, and that of GNPs was observed at 552 nm. TEM micrographs indicated spherical morphology of synthesized nanoparticles for both the cases with some deviations in GNPs. Spherical shape SNPs lie in between 10 and 30 nm and GNPs are in the range of 15-40 nm. Surface enhanced Raman scattering (SERS) activity of synthesized NPs was investigated using Rhodamine 6 G (R6G). When compared to standard R6G Raman spectrum, significant Raman enhancement was observed in R6G- nanoparticles conjugate. When applied for the SERS detection of DNA, well resolved Raman peaks were observed in SERS spectrum of DNA with the synthesized nanoparticles which favors the application of biosynthesized nanoparticles as SERS substrate.

Extract of raphanus raphanistrum peel waste as reducing agent for the synthesis of silver and gold nanoparticles

Raphanus raphanistrum peel waste extract is utilized for the biological synthesis of silver nanoparticles (Ag NPs) and gold nanoparticles (Au Nps). UV-Visible spectroscopy, scanning electron microscopy, energy-dispersive X-ray spectroscopy, Fourier transform infrared spectroscopy and X-ray powder diffraction analyses are performed to characterize NPs. Further, the catalytic behavior of prepared NPs is elucidated against methylene blue and congo red as model pollutants in the presence of sodium borohydride as a reducing agent. Au NPs have degradation efficiency of 66% and 61% against methylene blue and congo red which is higher than Ag NPs which shows 28% and 25% respectively

Green Synthesis of Gold Nanoparticles, Silver Nanoparticles and Gold-Silver Alloy Nanoparticles Using Ziziphus spina-christi Leaf Extracts and Antibacterial Activity against Multidrug-Resistant Bacteria

Multidrug-resistant bacteria continue to pose the greatest threat to public health. Metallic nanoparticles are one of the more promising strategies for combating antibiotic resistance. This research aims to determine the effect of gold and silver nanoparticles and gold-silver alloy nanoparticles as antibacterial agents. On the other hand, biogenic synthesized gold and silver nanoparticles using Ziziphus spina-christi leaf extract and preparation of gold-silver alloy nanoparticles for treatment of multidrug-resistant bacteria were studied. The formation of nanoparticles was characterized using ultraviolet-visible spectrophotometer, fourier transforms infrared spectroscopy, X-ray diffraction and transmission electron microscopy. Antibacterial activity of the biosynthesized gold nanoparticles, silver nanoparticles and gold-silver alloy nanoparticles was studied against Klebsiella pneumoniae, Escherichia coli, Pseudomonas aeruginosa, Staphylococcus aureus, Acinetobacter baumannii and Enterococcus faecalis. In the present study, the minimum inhibitory concentration ranged from 61.33 to 64 μg/ml and the minimum bactericidal concentration of the silver nanoparticles ranged from 85.33 to 93.33 μg/ml against multidrug-resistant strains. Synthesized gold nanoparticles had no inhibition zone, indicating that silver nanoparticles have no negative effect on multidrug-resistant bacteria. Minimum inhibitory concentration of gold nanoparticles was in high concentration against multidrug-resistant strain was not bactericidal. The highest minimum inhibitory concentration of gold nanoparticles was 114 μg/ml. Finally, the minimum inhibitory concentration ranged from 53.33 to 62 μg/ml and the minimum bactericidal concentration of the gold-silver alloy nanoparticles ranged from 77.33 to 93.33 μg/ml against multidrug-resistant strains. These results indicate that gold-silver alloy nanoparticles showed higher antimicrobial ability when compared to silver nanoparticles and gold nanoparticles alone. Finally, the synthesized nanoparticles could be used as an alternative antimicrobial agent against multidrug-resistant bacteria, according to our findings.

Renewable Polysaccharide and Biomedical Application of Nanomaterials

Nanotechnology being undoubtedly an uncut gem over the past few years has been in sighting as a new form of branch with its vigorous discoveries which have led to its divergent evolution giving emergence not only in the pathway of knowledge but also developing technological techniques. The constituting nanoparticles and its versatile properties with dynamic structures have made a major breakthrough in the past few years for its role in biotechnology arising nanobiotechnology, antipollution, renewable polymers, and its biomedical applications. Nanostructure composites forming nanomaterials on the basis of its working are pectin, cellulose, lignin, hyaluronic acid, bacterial cellulose, Arabic gum, and bacterial biosurfactants. In the recent years, it is seen that nanocomposites are giving promising results in medical technology incorporating with useful metal nanoparticles such as silver nanoparticles (AgNPs), gold nanoparticles (AuNPs), diamond nanoparticles, zinc oxide (ZnO), and titanium oxide (TiO). Some useful biomedical applications are in anticancerous, sunscreen, antiageing, and antitumorous. They have shown to be nontoxic at a certain level. Nanoparticle composites have proven with right amount of doping, and experienced techniques have given excellent results. Nanofibers of biodegradable poly(L‐lactide) (PLLA)/poly(lactide‐co‐glycol ide) (PLGA) compounds are used in drug delivery, folate redox‐responsive chitosan nanoparticles (FTC‐NPs) also as anticancer drug delivery, and mesoporous silica nanoparticles‐silver nanoparticles as a tissue growth in vivo processes. The study of a biosynthetic pathway of therapeutic drugs is still much needed. Waste management of renewable nanopolymers are an ultimate goal so that there are less haphazard elements towards the environment.

Involvement of gold and silver nanoparticles in lung cancer nanomedicines: A review

The use of nanoparticles in cancer therapies has spawned a new field of study known as cancer nanomedicines. Gold and silver nanoparticles are advantageous in both diagnostic and therapies. It’s an astonishment to see the benefits and application of metal nanoparticles over traditional therapy. Its medications are more effective. Physical, chemical, and biological processes are used to make gold nanoparticles (AuNPs) and silver nanoparticles (AgNPs). To destroy cancer cells, NPs grab incoming photons and change these into heat. AgNPs are primarily employed for antibacterial and anticancer therapy. In this article, we conclude with the uses of these nanoparticles as anti-cancer agents and the various methods through which they destroy cancer cells. Nanoparticle-based medicines are leading the way in primary and metastatic lung cancer diagnosis, imaging, screening, and therapies. This study covers recent accomplishments and obstacles in nanoparticle-based drug delivery systems with a focus on lung cancer therapy.

Recent Advances in the Development of Noble Metal NPs for Cancer Therapy.

With the development of nanotechnology, noble metal nanoparticles are widely used in the treatment of cancer due to their unique optical properties, excellent biocompatibility, surface effects, and small size effects. In recent years, researchers have designed and synthesized a large number of nanomedicines that can be used for cancer treatment based on the morphology, physical and chemical properties, mechanism of action, and toxicological studies of noble metal nanoparticles. Furthermore, the integration of diagnosis and treatment, hyperthermia, cytotoxicity research, and drug delivery system based on the study of noble metal nanoparticles can be used as effective means for cancer treatment. This article focuses on the analysis of noble metal nanoparticles that are widely used in the treatment of cancer, such as gold nanoparticles, silver nanoparticles, platinum nanoparticles, and palladium nanoparticles. The various methods and mechanisms of action of noble metal nanoparticles in the treatment of cancer are objectively summarized in detail. Based on the research on the therapeutic safety and toxicity of noble metal nanoparticles, the development prospect of noble metal nanoparticles in the future clinical application is prospected.

Incorporations of gold, silver and carbon nanomaterials to kombucha-derived bacterial cellulose: Development of antibacterial leather-like materials

Bacterial cellulose (BC), derived from kombucha scoby have extraordinary organoleptic properties suitable for development of leather-like materials. An improvement in physical and mechanical property is desirable for the practical applications. This work deals with the treatment of BC by incorporations of three different nanomaterials such as gold nanoparticles (AuNP), silver nanoparticles (AgNP) and graphene oxide (GO). Achieving combined benefits via synergic interactions of different nanomaterials is the major objective herein. While graphene oxide can influence some of the parameters related to mechanical properties, silver nanomaterials can offer antibacterial characteristics. Gold nano materials can bridge the BC/silver/graphene oxide as well as provide the desirable aesthetic colour. Different physical chemical and mechanical characteristics were studied in detail. For example, changes in morphology by imaging fiber network were studied using scanning electron microscopy. Fibre properties were studied by Small Angle X-Ray Scattering (SAXS) and X-Ray Diffraction (XRD). Elemental composition was studied by X-ray photoelectron spectroscopy (XPS) analysis and Raman analysis. The improvement of hydrophobicity was studied by Contact angle meter. Thermal analysis was performed using thermogravimetric analysis (TGA) and differential scanning calorimetry (DSC). A Picture was provided in ESI to show the modified material's leather-like appearances.