Naringin and Naringenin Functionalized Silver Nanoparticles: Synthesis, Characterization and Biological Evaluation

In recent time, green synthesis of metal nanoparticles is the latest developing technology and received prodigious interest because it is easy, environmentally pristine, non-fouling, antitoxic, and lowcost approach. Green route of biogenic synthesis of metal nanoparticles via microbes such as bacteria, fungi, virus, yeast and algae has the potential to deliver sustainable and enviro safe protocol. Green synthesized metal nanoparticles are the most optimistic and novel agent for various catalytic and biological activities as antibacterial, antiviral, anticancer etc. without any toxic effects. Here, we reviewed algae-mediated green synthesis of metal and metal oxide nanoparticles and their biological activity. Algae are photoautotrophic, eukaryotic, aquatic, unicellular or multicellular organisms. Algae commonly used for biosynthesis because they grow rapidly, their biomass growth on average ten times faster than higher plants and easy to handle experiments with algal species. Different algal strains such as red, green and brown algae are using for the green synthesis of metal nanoparticles. Algae contain bioactive molecules and secondary metabolites that act as reducing, capping and stabilizing agent for manufacturing in nanoparticles. Biogenically synthesized metal and metal oxide nanoparticles characterized by different techniques such as UV-visible spectroscopy, SEM (scanning electron microscopy), HR-TEM (high-resolution transmission electron microscopy), XRD (X-ray diffraction), TGA (thermogravimetric analysis), DLS (dynamic light scattering) zeta potential and exhibited biological activity. In future, research algal production of metal nanoparticles can be explored by the use of different microalgae and their applications in different areas such as biological activity, catalytic activity in the synthesis of organic compounds, medical diagnose and synthesis of nanocomposite, lipid nanoparticles and antibiofilm.

Green synthesis of metal nanoparticles using plant extract is an eco-friendly and cost-effective method for synthesizing metal nanoparticles. In this present work silver nanoparticles have been synthesized using ethanolic extract of Mimosa Pudica Linn plant (MPL) leaves. Green synthesized silver nanoparticles (AgNps) have been characterized by UV-Vis spectrometer, Fourier Transform Infra-Red ((FTIR) spectra, dynamic light scattering (DLS), Scanning Electron Microscopy (SEM) and X-ray diffraction (XRD) methods. UV-Vis spectrum of synthesized silver nanoparticles from Mimosa pudica Linn leaves extract shows a characteristic absorption peak at 421 nm. FTIR analysis reveals that presence of silver nanoparticles the presence of some biomolecules in extracts that act as reducing and capping agent for green synthesis of silver nanoparticles. DLS analysis showed AgNPs are drifted widely from 58.6 to 157.7 nm, with an average particle size of 104.7 nm. The particles are found to be polydisperse and slightly agglomerated due to the presence of phytochemicals present in the plant extract. Scanning electron microscope showed silver nanoparticles are spherical shaped. The XRD pattern revealed the presence of crystalline, dominantly spherical silver nanoparticles in the sample having size ranging from 42 to 50 nm. The XRD peaks 38.08, 44.22, 64.42, and 77.32 for leaves extract and 38.1, 44.3, 64.5, 77.5, and 81.33 for callus extract can be assigned the plane of silver crystals (111), (200), (220), and (311), respectively, and shows face-centered, cubic and crystalline nature of the silver nanoparticles. The green synthesized silver nanoparticles show significant antibacterial activity.

Green synthesis of metal nanoparticles is an attractive substitute for traditional methods using capping and reducing chemicals. In this study, silver nanoparticles (AgNPs) were synthesised using carbon dots (CDs) derived from bioresources as reducing, protecting, and stabilising agents in a single step using environmentally friendly and cost-effective synthetic methods. The optical and structural properties of prepared CD/AgNPs were explored using UV–vis (Ultraviolet-Visible Spectroscopy), Fluorescence spectroscopy, XRD (x-ray Diffraction), DLS (Dynamic Light Scattering), SEM-EDX (Scanning Electron Microscopy with Energy-Dispersive x-ray Spectroscopy) and TEM (Transmission Electron Microscopy). The synthesised CD/AgNPs are stable as zeta potential value is −14.7mV. From TEM the particle size exhibited as ∼12 nm. The prepared CD/AgNPs exhibited significant optical absorbance, good water dispersibility, stability and nano size. Also, CD/AgNPs revealed good biocidal effects against Gram-negative bacteria Escherichia coli (E. coli), Pseudomonas Aeruginosa (P. aeruginosa), Gram-positive Staphylococcus Aureus (S. aureus), Bacillus Cereus (B. cereus), and good anti-fungal activity against Aspergillus Niger (A. niger). The CD/AgNPs were further analyzed by live/dead assay. E. coli and A. niger with zone of inhibition around 3.1 and 40 mm, respectively when compared to ciprofloxacin (2.2 mm) and fluconazole (25 mm). The above investigation proved that the developed CD/AgNPs will be a new platform as an alternative to the traditional antibiotics for the generation of new kind of antibacterial materials and also provide the pathway for various metal/CD nanomaterials for diverse biomedical applications.

Green synthesis (GS) is a vital method for producing metal nanoparticles with antimicrobial properties. Unlike traditional methods, green synthesis utilizes natural substances, such as plant extracts, microorganisms, etc., to create nanoparticles. This eco-friendly approach results in non-toxic and biocompatible nanoparticles with superior antimicrobial activity. This paper reviews the prospects of green synthesis of metal nanoparticles of silver (Ag), copper (Cu), gold (Au) and metal oxide nanoparticles of zinc (ZnO), magnesium (MgO), cobalt (Co3O4), and titanium (TiO2) using plant extracts from tissues of leaves, barks, roots, etc., antibacterial mechanisms of metal and metal oxide nanoparticles, and obstacles and factors that need to be considered to overcome the limitations of the green synthesis process. The clean surfaces and minimal chemical residues of these nanoparticles contribute to their effectiveness. Certain metals exhibit enhanced antibacterial properties only in GS methods due to the presence of bioactive compounds from natural reducing agents such as Au and MgO. GS improves TiO2 antibacterial properties under visible light, while it would be impossible without UV activation. These nanoparticles have important antimicrobial properties for treating microbial infections and combating antibiotic resistance against bacteria, fungi, and viruses by disrupting microbial membranes, generating ROS, and interfering with DNA and protein synthesis. Nanoscale size and large surface area make them critical for developing advanced antimicrobial treatments. They are effective antibacterial agents for treating infections, suitable in water purification systems, and fostering innovation by creating green, economically viable antibacterial materials. Therefore, green synthesis of metal and metal oxide nanoparticles for antibacterial agents supports several United Nations Sustainable Development Goals (SDGs), including health improvement, sustainability, and innovation.

Nanotechnology is the science that deals with matter on the nanoscale, with sizes ranging from 1 to 100 nm. It involves designing, synthesising, characterising and applying these nanoscale materials. Nanoparticles (NPs) are known for their high surface-area to volume-ratio, surface charge density, low melting point, and distinguishably good optical/electrical properties. NPs exhibit an excellent drug delivery system, an effective contrast agent for vascular imaging, and effective antimicrobial activity. The biological synthesis of NPs is a simple, cost-effective, and environmentally friendly technique. This bottom-up technique utilises organisms' enzymes/bio-compounds and a plant extract as capping and reducing agents. Cinnamomum species are known for their intrinsic antimicrobial, antidiabetic, antioxidant, anti-inflammatory, anticancer, and neuroprotective properties. This review summarises articles that greenly synthesised NPs using Cinnamomum species' extracts, describing their methodologies, characterisation of the nanoparticles and their medical applications. A literature search has been conducted on databases PubMed, ScienceDirect, and Frontier on the green synthesis of metal nanoparticles (MNPs) using Cinnamomum-based extracts. Various articles reported the methodology of utilising Cinnamomum species' extracts as reducing and capping agents. Only original lab articles were considered. Various types of MNPs have been successfully synthesised. The most common Cinnamomum species utilised as extracts is Cinnamomum tamala. The most common applications tested were the MNPs' antibacterial, antiviral, antifungal, antidiabetic and anticancerous activity. MNPs also had a role in treating mice-induced polycystic ovarian syndrome and Parkinson-like neurodegenerative diseases. Cinnamomum species have been successfully utilised in the green synthesis of various MNPs. Silver and Gold NPs were the most reported. These MNPs proved their efficacy in multiple fields of medicine and biology, especially their antibacterial, antiviral and antifungal activity. Notably, the newly synthesised NPs showed promising results in treating polycystic ovarian syndrome in rats.

Nanoparticle properties are correlated to their size, size distribution, and shape; it is essential to accurately measure these features in the field of nanoscience. In this study, silver nanoparticles (AgNPs) were synthesized with the ultrasonic-spray-pyrolysis (USP) method from a water solution of silver nitrate. The synthesized AgNPs were characterized by Dynamic Light Scattering (DLS) analysis and Scanning Electron Microscopy (SEM) to reveal their size and size distribution. A search algorithm based on an image-processing technique to obtain particle size and particle-size distribution from SEM micrographs is proposed. In order to obtain more quantitative information and data with respect to the morphology of particles synthesized under different process parameters, SEM micrographs with a nonhomogeneous background contrast were examined via image-processing techniques in MATLAB. Due to the inhomogeneous contrast of SEM micrographs, defining an overall threshold value was insufficient in the detection of whole nanoparticles. Thus, subimages were directly created according to the maximum and minimum particle size specified by the user to determine local threshold values. The obtained results were automatically combined to represent both particle dimension and location in the SEM micrographs. We confirmed that the results of our DLS analysis, theoretical calculation, and image-processing technique were correlated with our expected results.

Despite the widespread utilization of Dynamic Light Scattering (DLS) as an analytical tool for particle sizing, one of the critical questions raised among the users is on how to do proper analysis and interpretation of the data obtained. In view of this, the present work was done to reveal the role of particle-particle interaction towards the interpretation of Z-average and the three types of particle size distributions (intensity-weighted, volume-weighted, and number-weighted) obtained from DLS analysis. Experimental results showed that Z-average for the weakly-interacting (highly stable) SiO2 particles obtained from DLS was almost identical to that gained from TEM analysis. Meanwhile, for the strongly-interacting (non-stable, aggregating) bare Fe3O4 particles, the Z-average obtained from DLS was ∼10 times larger than TEM result. In term of particle size distributions, it was found that all the three types of size distributions were closely collapsed into a single bell curve for the unimodal and monodisperse SiO2 particles; while for bare Fe3O4 particles which had been aggregated into polydisperse structures, the three size distributions exhibited large variation from each other. This observation implies that choosing the right size distribution become challenging in the latter case. Additionally, it was found that the Z-average of bare Fe3O4 particles varied significantly with the particle concentration used for DLS measurement. Concerning with particle aggregation kinetic, results from three independent case studies showed that the intensity-weighted distribution provides more logical and consistent right shifting as compared to both volume-weighted and number-weighted distributions.

Objective(s): Nowadays, nanoparticles bio production, considering their performance in medicine and biological science, is increasing. Green synthesis of metal nanoparticles using organisms has emerged as a nontoxic and ecofriendly method for synthesis of metal nanoparticles The objectives of this study were the production of silver nanoparticles using Avena sativa L. extract and optimization of the biosynthesis process. The effects of quantity of substrate (silver nitrate (AgNo3)) and temperature on the formation of silver nanoparticles are studied. Methods: In this work, silver nanoparticles were synthesized from an extract of Avena sativa L. at different temperatures (30° C, 60° C, 90° C ) and AgNo3 concentrations( 1 mM, 2mM, 4mM) . The morphology and size of the nanoparticles were determined using Scanning Electron Microscope (SEM) and Dynamic Light Scattering (DLS). Results: SEM images showed that by increasing temperature nanoparticles size were decreased and by increasing concentrations of AgNo3 the number of nanoparticles was increased. Conclusions: The results indicated that by increasing the reaction temperature, the size of the nanoparticles would decrease. Also by increasing the concentrations of AgNo3, the amount of produced nanoparticles would be increased, but won't have a significant effect on its size. The preparation of nano- structured silver particles using Avena sativa L. extract provides an environmentally friendly option as compared to currently available chemical/ physical methods.

CdS is an important wide bandgap chalcogenides most popularly studied for various optoelectronics and biosensing applications. In this study, CdS Nanoparticles (NPs) have been prepared successfully by chemical co-precipitation method, using cadmium acetate and sodium sulphide as precursors. A comparative study of average particle size calculated by Scherrer Plot, Uniform Deformation Model (UDM), Dynamic Light Scattering (DLS) analysis and Brus Model has been done here. The structural and optical behaviour of synthesized samples were investigated via X-ray diffraction (XRD), DLS and UV–Visible Spectroscopy. The XRD spectra of the prepared CdS NPs revealed the crystalline phase having cubic structure. The average particles size has been studied via Debye Scherrer equation and Scherrer Plot. For the theoretical calculations of particle size along with the induced lattice strain, considering the broadening effect of lattice strain, Williamson-Hall analysis was employed. Assuming the lattice strain to be isotropic in nature, UDM was applied for calculation. The particles size distribution profile in terms of volume as well as intensity was recorded using DLS analysis in ethanol medium at room temperature. Besides this, the energy bandgap was obtained by applying Tauc model in the recorded absorption spectra. The obtained value of bandgap was used in Brus model for estimating the average particle size. The obtained comparative results show that the average particle size of the prepared CdS NPs estimated from Scherrer equation, Scherrer plot, UDM plot and Brus model are almost similar and lies in the range of 2-5 nm whereas the results of DLS showed wide variation in the range of 40-600 nm.

Purpose: Identification of structural-geometrical parameters, technological properties and elemental composition of spherical powders in a wide fraction range with respect to the VT20 alloy has been carried out. This is important for evaluating the optimum filling of a given volume by mixture of powders of different fractions during 3D printing. Design/methodology/approach: During the investigation of spherical Ti-alloy powders, a comprehensive approach was performed using Scanning Electron Microscopy (SEM), Energy-Dispersive X-ray Spectroscopy (EDS), Dynamic Light Scattering (DLS) and Inductively Coupled Plasma Mass Spectrometry (ICP-MS). The surface morphology of the powders was studied on a Tuescan Vega 3 Scanning Electron Microscope. Using the Quantax energy dispersive spectrometer, element distribution maps were obtained and histograms of element distribution in the investigated powders were constructed. ICP-MS analysis was performed to clarify the elemental composition. DLS analysis using Malvern's Zetasizer Nano-ZS equipment allowed us to determine the functional parameters (hydrodynamic radius – Rh, zeta potential – z and specific conductivity) of particles of titanium alloy powder that indirectly indicate a tendency to form conglomerates. Findings: According to the microscopic examinations, the VT20 alloy powder consists of globular-shaped particles with the lamellar traces on their surfaces. The uniformity of the chemical element distribution within each fraction of the investigated powders was confirmed by EDS, and the full conformity of the powder fractions with the elemental composition of the VT20 alloy was confirmed by ICP-MS. The DLS method allowed to establish that the formation of conglomerates would not occur within the studied fractions of the VT20 alloy powder. Research limitations/implications: The use of high sensitive investigation methods gives understanding of the mechanisms of fine structure formation and possibility to control the processes of powder coagulation in the stage of electrostatic interactions. Practical implications: The obtained results can be used for the formation of fine spherical particles of the powder, but at the same time, these technologies can be extended for the particles of non-spherical shape. Originality/value: The DLS method allowed to establish that the formation of conglomerates would not occur within the studied fractions of the VT20 alloy powder. This, in turn, will improve powder melting during 3D printing. The measured zeta potential values allowed us to reveal mechanisms of fine structure formation and to control the processes of powder coagulation in the stage of electrostatic interactions.

The current study aims to synthesise silver (Ag) nanoparticles using Aloin with a focus on antibacterial, antioxidant, and anticancer activity. The biosynthesis of nanoparticles has been designed as a profitable and environmentally friendly alternative to chemical and physical methods. The UV-Visible spectrum was used to determine the silver nanoparticles, which were synthesised using Aloin. Scanning electron microscopy (SEM), zeta potential, and dynamic light scattering (DLS) were used to further characterise it. The Aloin was also subjected to a Fourier transform infrared analysis.The absorption peak at 439nm in the UV-Visible absorption spectrum of the synthesised silver nanoparticles demonstrates the formation of silver nanoparticles in solution. The shape of the Ag nanoparticles was revealed by SEM analysis. The IR spectra revealed that Aloin extract contains six functional groups. The nanoparticles synthesised are highly stable, with an average particle size of 130.7nm, as confirmed by zeta potential and DLS analysis. The nanoparticles produced were antibacterial and antioxidant in nature. It has a strong cytotoxic effect on breast cancer cell lines.  According to the current study, the synthesis route can be used on a large scale in the food industry for food preservation and these Ag nanoparticles can be used for its therapeutic purposes to develop a new drug to treat cancer because it is not dependent on factors like high energy, prolonged preparation times, and specialised equipment.

The green synthesis of metal nanoparticles has received substantial attention due to their applications in various domains. The aim of the study was to obtain silver nanoparticles (AgNPs) by green synthesis with filamentous fungi, such as Cladosporium cladosporoides, Penicillium chrysogenum, and Purpureocillium lilacinum. Fungal species were grown on nutrient media and aqueous mycelium extracts were used to reduce Ag+ to Ag (0). The silver nanoparticles were analyzed by various techniques, such as UV-Visible spectroscopy (UV-Vis), scanning electron microscopy (SEM), Fourier transform infrared spectroscopy (FTIR), transmission electron microscopy (TEM), dynamic light scattering (DLS), and Zeta potential. The formation of silver nanoparticles was confirmed by UV-Vis spectroscopy and the color change of the mixture containing metal precursor and aqueous mycelium extract. FTIR displayed different functional groups as capping and reducing agents for the biosynthesis of AgNPs. SEM and TEM provided information on the particles’ morphology. DLS diagrams indicated mean particle diameters in the 124–168 nm region. All biosynthesized AgNPs had negative zeta values, which is a sign of good stability. Silver nanoparticles were evaluated for antimicrobial activity, and the most active were those synthesized with metabolites from Cladosporium, leading to 93.75% inhibition of Staphylococcus aureus, 67.20% of Escherichia coli, and 69.56% of Candida albicans. With the highest microbial inhibition percentage and a very good Poly Dispersion Index (Pd I), Cladosporium cladosporoides was selected as an environmentally friendly source of silver nanoparticles that could be used as a potential antimicrobial agent.

Objective: The aim of the present study is to synthesize the silver (Ag) nanoparticle using Aloin with a focus on its antibacterial, antioxidant, and anticancer activity.
 Methods: The silver nanoparticles were synthesized using Aloin and were determined by UV-Visible spectrum. It was further characterized by scanning electron microscope (SEM), zeta potential, and dynamic light scattering (DLS). The Fourier transform infrared analysis was also carried out for the Aloin. 
 Results: The UV-Visible absorption spectrum of the synthesized silver nanoparticles has shown the absorption peak at 439nm which proves the formation of silver nanoparticles in the solution. The SEM analysis revealed that the Ag nanoparticles were spherical in shape. The IR spectra showed that there are 6 functional groups are present in Aloin extract. The synthesized nanoparticles are found to be highly stable with an average particle size of 130.7nm which was confirmed by zeta potential and DLS analysis. The synthesized nanoparticles had a good antibacterial and antioxidant activity. It shows a very good cytotoxic effect against breast cancer cell line.
 Conclusion: The present study suggests that the synthesis route is free from the requirements such as high energy, extended preparation time, and special equipments and thus can be used for large-scale synthesis in food industries for food preservation and these Ag nanoparticles can be used for its therapeutic purposes for developing a new drug against cancer.

Hepatoprotective effect of engineered silver nanoparticles coated bioactive compounds against diethylnitrosamine induced hepatocarcinogenesis in experimental mice

In the present study, a simple, fast and eco-friendly biosynthesis of silver nanoparticles (AgNPs) using Mentha langifolia leaf extract as the reducing agent was investigated. Nanoparticles forming were indicated by the color changes in solution and were confirmed by UV-Vis spectrum, FT-IR analysis and Scanning Electron Microscopic (SEM) micrograph. The average particle size of produced AgNPs was determined by dynamic light scattering (DLS) technique. Further, the antibacterial activity of synthesized AgNPs was evaluated against Streptococcus pneumonia and staphylococcus epidermidis as Gram-positive bacteria and Salmonella enterica and enterobacter aerogenes as Gram-negative bacteria. Minimum inhibitory concentration (MIC) and minimum bactericidal concentration (MBC) of biosynthesized silver nanoparticles were determined. UV-Visible spectrophotometer showed absorbance peak in 340 nm. DLS analysis indicated that the average size of AgNPs is 21.1nm. The results of SEM showed that synthesized AgNPs are spherical in shape. The antibacterial activities of the silver nanoparticles were studied against subject bacteria. The present report explores a rapid, simple and economical route, without any hazardous chemicals as reducing or stabilizing agents to synthesis AgNPs and describes the antimicrobial activities of synthetized silver nanoparticles.