Preparation of silver iodide nanoparticles using laser ablation in liquid for antibacterial applications

Velocity Map Imaging Photoelectron Spectroscopy of Silver Iodide Aerosol Particles

The valence band electronic structure of isolated silver iodide nanoparticles (AgI NP) was investigated by vacuum-ultraviolet aerosol photoelectron spectroscopy using the velocity map imaging technique (VUV VMI-PES). The VUV VMI-PES results were obtained for polydisperse aerosol produced by aggregation of hydrocolloid of silver iodide particles 8-15 nm in size. The ionization energy of the AgI particles was found to be 6.0±0.1 eV with respect to the vacuum level. The DFT calculations showed that the main contribution to the density of AgI electronic states in the valence region originates from I 5p orbitals. The dependence of the asymmetry parameter on the electron energy showed that the value of the characteristic energy loss of excited photoelectrons was 2.7 eV, which coincided with the band gap of the nanomaterial.

Silver Nanoparticles: Synthesis, Structure, Properties and Applications

Silver nanoparticles (Ag NPs) have accumulated significant interest due to their exceptional physicochemical properties and remarkable applications in biomedicine, electronics, and catalysis sensing. This comprehensive review provides an in-depth study of synthetic approaches such as biological synthesis, chemical synthesis, and physical synthesis with a detailed overview of their sub-methodologies, highlighting advantages and disadvantages. Additionally, structural properties affected by synthesis methods are discussed in detail by examining the dimensions and surface morphology. The review explores the distinctive properties of Ag NPs, including optical, electrical, catalytic, and antimicrobial properties, which render them beneficial for a range of applications. Furthermore, this review describes the diverse applications in several fields, such as medicine, environmental science, electronics, and optoelectronics. However, with numerous applications, several kinds of issues still exist. Future attempts need to address difficulties regarding synthetic techniques, environmental friendliness, and affordability. In order to ensure the secure utilization of Ag NPs, it is necessary to establish sustainability in synthetic techniques and eco-friendly production methods. This review aims to give a comprehensive overview of the synthesis, structural analysis, properties, and multifaceted applications of Ag NPs.

A novel facile synthesis of metal nitride@metal oxide (BN/Gd2O3) nanocomposite and their antibacterial and anticancer activities

In this study, a novel core/shell nanocomposite structure (h-BN@Gd2O3 NCs) was created for the first time by combining hexagonal boron nitride (h-BN) with doped gadolinium oxide (Gd2O3) using different laser pulse numbers, i.e., 150, 338, and 772 pulses. We employed various analytical techniques, including mapping analysis, FE-SEM, EDS, HRTEM, SAED, XRD, zeta potential analysis, DLS, FTIR, Raman spectroscopy, and PL measurements, to characterize the synthesized h-BN, c-Gd2O3, and h-BN@Gd2O3 NCs (338 pulses). XRD results indicated hexagonal and cubic crystal structures for BN and Gd2O3, respectively, while EDS confirmed their chemical composition and elemental mapping. Chemical bonds between B-N-Gd, B-N-O, and Gd-O bands at 412, 455, 474, and 520 cm-1 were identified by FTIR analysis. The antimicrobial and anticancer activities of these NCs using agar well diffusion and MTT assays. They exhibited potent antibacterial properties against both Gram-positive and Gram-negative pathogens. Furthermore, NCs have reduced the proliferation of cancerous cells, i.e., human colon adenocarcinoma cells (HT-29) and human breast cancer cells (MCF-7), while not affecting the proliferation of the normal breast cell line (MCF-10). The anticancer efficacy of NCs was validated by the AO/EtBr assay, which confirmed apoptotic cell death. Blood compatibility on human erythrocytes was also confirmed by hemolytic and in vitro toxicity assessments. The compiled results of the study proposed these nanoparticles could be used as a promising drug delivery system and potentially in healthcare applications.

Ozonation/UV irradiation of dispersed Ag/AgI nanoparticles in water resources: stability and aggregation

Proliferation of nanoparticles (NPs) as aqueous pollutants is a matter of growing concern today. The aggregation kinetics of colloidal bare silver (Ag, 20.5 nm) and silver iodide (AgI, 15.3 nm) NPs were investigated during ozone/ultraviolet (O₃/UV) oxidation. Dynamic light scattering was applied to monitor the aggregation of NPs, and the z-average of treated samples was considered aggregate diameter. The effect of temperature, pH, and initial concentration of NPs was investigated on the aggregation rate constant and stability ratio. At a short oxidation period of approximately 1 min, the lower stability ratio was achieved for Ag NPs (< 50) than AgI NPs (> 100). Under acidic conditions, the negative surface charge of both NPs was neutralized that resulted in faster aggregation. In contrast, the impact of temperature and initial concentration of NPs on the aggregation rate was different for both NPs, which was due to the type of O₃/UV interaction with the surface of NPs and the thickness of the electrical double layer surrounding the NPs. The aggregation behavior of Ag NPs obeyed diffusion-limited regime, while an intermediate regime between diffusion- and reaction-limited was observed for AgI NP aggregation. The resulting aggregate morphologies showed that the clusters were ramified for Ag and compressed for AgI NPs. Applying the O₃/UV oxidation process for water treatment purposes leads to a significant reduction in aggregation time for inherently unstable Ag and stable AgI toxic NPs from several hours or days to several minutes.

Biogenesis and characterization of proficient silver nanoparticles employing marine procured fungi Hamigera pallida and assessment of their antioxidative, antimicrobial and anticancer potency

OBJECTIVE

To assess the anticancer potential of biosynthesized silver nanoparticles using marine derived fungi Hamigera pallida with their antibacterial and antioxidant activities.

RESULTS

The biosynthesis of silver nanoparticles (AgNPs) was assessed by the change in color from bright yellow to dark brown. UV-Visible spectroscopy revealed its stability at 429 nm; ATR-FTIR spectroscopy revealed the functional group responsible for its production; X-Ray Diffraction revealed its crystalline FCC structure resembling the peaks in the XRD pattern, corresponding to (110), (111), (200), and (311) planes; TEM imaging revealed its spherical morphology with an average particle size of 5.85 ± 0.84 nm ranging from 3.69 to 16.11 nm and Tauc's plot analysis revealed a band gap energy of 2.22 eV, revealing aptitude of AgNPs as a semiconductors. The subsequent characterization results revealed the effective synthesis of silver nanoparticles. The biosynthesized AgNPs were found to have significant antimicrobial effect against three Gram-positive and three Gram-negative bacteria. They also demonstrated higher antioxidative potential by demonstrating strong radical scavenging activity against DPPH (2, 2-diphenyl-1-picrylhydrazyl). AgNPs showed highest anticancer activity (62.69 ± 1.73%) against human breast cancer (MCF-7) cell line at 100 µg/mL with the IC₅₀ value of 66.07 ± 2.17 µg/mL.

CONCLUSIONS

This study revealed the prospect for further utilization of AgNPs by Cell free filtrate of Hamigera pallida as an antibacterial, antioxidative and anticancer agents.

Recent progression of cyanobacteria and their pharmaceutical utility: an update

Cyanobacteria (blue-green algae) are Gram-negative photosynthetic eubacteria that are found everywhere. This largest group of photosynthetic prokaryotes is rich in structurally novel and biologically active compounds; several of which have been utilized as prospective drugs against cancer and other ailments, as well. Consequently, the integument of nanoparticles-synthetic approaches in cyanobacterial extracts should increase pharmacological activity. Moreover, silver nanoparticles (AgNPs) are small materials with diameters below 100 nm that are classified into different classes based on their forms, sizes, and characteristics. Indeed, the biosynthesized AgNPs are generated with a variety of organisms, algae, plants, bacteria, and a few others, for the medicinal purposes, as the bioactive compounds of curio and some proteins from cyanobacteria have the potentiality in the treatment of a wide range of infectious diseases. The critical focus of this review is on the antimicrobial, antioxidant, and anticancer properties of cyanobacteria. This would be useful in the pharmaceutical industries in the future drug development cascades.Communicated by Ramaswamy H. Sarma.

Formulation, Characterization, Antioxidant, Cytotoxicity, and Anti-acute Leukemia Effects of Fe Nanoparticles

In this study, iron nanoparticles were prepared and synthesized in aqueous medium using Cinnamomum verum as stabilizing and reducing agents. We determined the anti-acute leukemia potentials of FeNPs against acute T cell leukemia and acute lymphoblastic leukemia cell lines. FeNPs inhibited half of the DPPH molecules in the concentration of 139 µg/mL. MTT assay was used on J.RT3-T3.5 (Acute T cell leukemia cell line), Jurkat, Clone E6-1 (Acute T cell leukemia cell line), MOLT-3 (Acute lymphoblastic leukemia cell line), TALL-104 (Acute lymphoblastic leukemia cell line), and HUVEC (Normal cell line) for analyzing of cytotoxicity and anti-acute leukemia effects of FeNPs. These nanoparticles had high cell death and anti-acute leukemia effects against J.RT3-T3.5, Jurkat, Clone E6-1, MOLT-3, and TALL-104 cell lines. Among the above cell lines, the best result of anti-acute leukemia properties of composite was gained in the cell line of Jurkat, Clone E6-1. All result showed the iron nanoparticles may be used as a chemotherapeutic treatment drug of leukemia in humans.

Exploring Dose-Dependent Cytotoxicity Profile of Gracilaria edulis-Mediated Green Synthesized Silver Nanoparticles against MDA-MB-231 Breast Carcinoma

Green-based synthesis of metal nanoparticles using marine seaweeds is a rapidly growing technology that is finding a variety of new applications. In the present study, the aqueous extract of a marine seaweed, Gracilaria edulis, was employed for the synthesis of metallic nanoparticles without using any reducing and stabilizing chemical agents. The visual color change and validation through UV-Vis spectroscopy provided an initial confirmation regarding the Gracilaria edulis-mediated green synthesized silver nanoparticles. The dynamic light scattering studies and high-resolution transmission electron microscopy pictographs exhibited that the synthesized Gracilaria edulis-derived silver nanoparticles were roughly spherical in shape having an average size of 62.72 ± 0.25 nm and surface zeta potential of -15.6 ± 6.73 mV. The structural motifs and chemically functional groups associated with the Gracilaria edulis-derived silver nanoparticles were observed through X-ray diffraction and attenuated total reflectance Fourier transform infrared spectroscopy. Further, the synthesized nanoparticles were further screened for their antioxidant properties through DPPH, hydroxyl radical, ABTS, and nitric oxide radical scavenging assays. The phycosynthesized nanoparticles exhibited dose-dependent cytotoxicity against MDA-MB-231 breast carcinoma cells having IC50 value of 344.27 ± 2.56 μg/mL. Additionally, the nanoparticles also exhibited zone of inhibition against pathogenic strains of Bacillus licheniformis (MTCC 7425), Salmonella typhimurium (MTCC 3216), Vibrio cholerae (MTCC 3904), Escherichia coli (MTCC 1098), Staphylococcus epidermidis (MTCC 3615), and Shigella dysenteriae (MTCC9543). Hence, this investigation explores the reducing and stabilizing capabilities of marine sea weed Gracilaria edulis for synthesizing silver nanoparticles in a cost-effective approach with potential anticancer and antimicrobial activity. The nanoparticles synthesized through green method may be explored for their potential utility in food preservative film industry, biomedical, and pharmaceutical industries.

Preparation of Iron Oxide and Titania-Based Composite, Core-Shell Populated, Nanoparticulates Material by Two-Step LASER Ablation in Aqueous Media as Antimicrobial and Anticancer Agents

Iron oxide and titania-based composite nanoparticles (NPs) populated with core-shell structures, as part of the mixture of the monometallic NPs, were prepared in water medium by the two-fluence LASER ablation technique by applying 30 and 60 mJ/cm2 LASER energy irradiations. The prepared monometallics, composite, and core-shell NPs structures were confirmed from the XRD, TEM, and EDX analyses, followed by the FE-SEM and UV absorptions. Optically, the NPs exhibited an increase in the energy gap from 3.27 eV to 3.75 eV as LASER fluence increased from 30 mJ/cm2 to 60 mJ/cm2. The average NPs core size distributions for the core-shell material ranged at ∼70 nm with the shell thickness around 20 nm. The biggest NPs were of ∼170 nm size which were sparsely distributed. The magnetization behaviors of the NPs were also investigated using the vibrating sample magnetometer (VSM). The NPs showed antimicrobial activities against the pathogenic species: Escherichia coli and Staphylococcus aureus. The antimicrobial activities of the synthesized NPs, synthesized under the influence of magnetic fields, were found to be more potent than the NPs synthesized without the presence of any magnetic field. The NPs prepared under the influence of the magnetic fields also comparatively exhibited higher levels of cytotoxicity against lung cancer cell lines (A549) than the NPs prepared under no magnetic field's influence by the similar energy level effects of the LASER fluence. The flow cytometry analyses confirmed the NPs' cytotoxic impacts against the human lung cancer A549 cell lines through the initiation of apoptosis and promotion of the cell cycle arrest at the G1 phase of cell division. To further confirm the cytotoxic effects and the mechanism of the anticancer activity of the synthesized NPs against the A549 cell lines, several related parameters (cell viability, membrane permeability, nuclear intensity, and cytochrome-C release) were analyzed using the high-content screening (HCS) assay. The study suggested that the prepared NPs have potential as antimicrobial and also as anti-lung-cancer agents as tested in vitro. These NPs can also be part of combined chemotherapy in different oncological interventions, as well as a sonosensitizer in sonomagnetic heating-based therapy, especially for cancers.

Evaluation of the Response of HOS and Saos-2 Osteosarcoma Cell Lines When Exposed to Different Sizes and Concentrations of Silver Nanoparticles

Osteosarcoma is considered to be a highly malignant tumor affecting primarily long bones. It metastasizes widely, primarily to the lungs, resulting in poor survival rates of between 19 and 30%. Standard treatment consists of surgical removal of the affected site, with neoadjuvant and adjuvant chemotherapy commonly used, with the usual side effects and complications. There is a need for new treatments in this area, and silver nanoparticles (AgNPs) are one potential avenue for exploration. AgNPs have been found to possess antitumor and cytotoxic activity in vitro, by demonstrating decreased viability of cancer cells through cell cycle arrest and subsequent apoptosis. Integral to these pathways is tumor protein p53, a tumor suppressor which plays a critical role in maintaining genome stability by regulating cell division, after DNA damage. The purpose of this study was to determine if p53 mediates any difference in the response of the osteosarcoma cells in vitro when different sizes and concentrations of AgNPs are administered. Two cell lines were studied: p53-expressing HOS cells and p53-deficient Saos-2 cells. The results of this study suggest that the presence of protein p53 significantly affects the efficacy of AgNPs on osteosarcoma cells.

Antibacterial and corrosion protection properties of SA-CuZnO@ODA-GO composite in circulating cooling water

The suitable temperature of circulating cooling water is conducive to the reproduction of bacteria, which will cause corrosion to the pipe and form slime on its surface. Therefore, the sterilization of circulating cooling water is an essential step. In this work, a new type of SA-CuZnO@ODA-GO composite antibacterial material with hydrophobic properties was prepared by ultrasonic treatment method. The composite was characterized and analyzed by SEM, TEM, XPS, XRD, and FT-IR. Then, the CuZnO@ODA-GO@PU hydrophobic and antibacterial coating was prepared. The antibacterial properties and mechanism of the composite were investigated by gram-positive bacteria S. aureus and gram-negative bacteria E. coli. The result shows that the best antibacterial rate of SA-CuZnO@ODA-GO composite antibacterial material is up to 99.10%. As for the SA-CuZnO@ODA-GO@PU composite antibacterial coating, the corrosion resistance of the antibacterial coating is up to 99.99%. The anticorrosion property is due to the hydrophobic modification of the composite, which can insulate the steel sheet from water. Secondly, due to the rigidity of the SA-CuZnO@ODA-GO, it combines with epoxy resin to form a compact structure.

A study of preparing silver iodide nanocolloid by electrical spark discharge method and its properties

This study employed an electric discharge machine (EDM) and the Electrical Spark Discharge Method (ESDM) to prepare silver iodide nanocolloid (AgINC). Povidone-iodine (PVP-I) was dissolved in deionized water to create a dielectric fluid. Silver material was melted using the high temperature generated by an electric arc, and the peeled-off material was reacted with PVP-I to form AgI nanoparticles (AgINPs). Six discharge pulse wave parameter combinations (Ton-Toff) were employed, and the resultant particle size and suspension of the prepared samples were examined. The results revealed that AgINPs were successfully created using the ESDM. When Ton-Toff was set at 90-90 μs, the zeta potential of the AgINC was - 50.3 mV, indicating excellent suspension stability. The AgINC particle size was 16 nm, verifying that the parameters yielded AgINPs with the smallest particle size distribution and highest zeta potential. Ultraviolet-visible spectrum analyser was performed to analyse the samples, and the spectra indicated that the characteristic wavelength was 420 nm regardless of the Ton-Toff values. X-ray diffraction analysis determined that the AgINPs exhibited two crystal structures, namely β-AgI and Ag. Transmission electron microscopy was performed and revealed that the particles were irregularly shaped and that some of the larger particles had aggregated. The crystal structure was determined to be a mixture of Ag and β-AgI, with a lattice spacing of 0.235 nm and 0.229 nm, respectively. The lattice spacing of the Ag was 0.235 nm. X-ray diffraction analysis indicated that the prepared AgINC were composed of only Ag and I; no additional chemical elements were detected.

Green Synthesis, Characterization, and Evaluation of the Antimicrobial Activity of Camellia sinensis Silver Nanoparticles

An extremely worrying and alarming increase in the level of multiple drug resistance is reported in Sudan, in which bacterial strains are becoming resistant to many commonly available antibiotics. Eventually, it is becoming extremely difficult to treat debilitating infections. In search of promising solutions to this arising crisis, Camellia sinensis silver nanoparticles were synthesized using the green synthesis method. The synthesis of the Camellia sinensis silver nanoparticles is confirmed using analytical methods as ultraviolet-visible spectroscopy, X-ray diffractometer, and scanning electron microscopy. Using the ultraviolet-visible spectroscopy, an absorption band of 412 nm was observed. Furthermore, scanning electron microscopy revealed the presence of silver nanoparticles which fell within the range of 1–100 nm, and X-ray diffractometer analysis showed three intense peaks with a maximum intense peak at 24.3 theta. Nanoparticles distribution between 12 nm and 64 nm was observed with an average diameter of 18.115 nm. It also revealed orthorhombic-shaped nanoparticles. The synthesized nanoparticles showed antimicrobial activity against Staphylococcus aureus with a zone of inhibition of 7 mm, but none was detected against Escherichia coli. The obtained physicochemical properties were correlated with the antibacterial activity of the silver nanoparticles.

A Review on Silver Nanoparticles: Classification, Various Methods of Synthesis, and Their Potential Roles in Biomedical Applications and Water Treatment

Recent developments in nanoscience have appreciably modified how diseases are prevented, diagnosed, and treated. Metal nanoparticles, specifically silver nanoparticles (AgNPs), are widely used in bioscience. From time to time, various synthetic methods for the synthesis of AgNPs are reported, i.e., physical, chemical, and photochemical ones. However, among these, most are expensive and not eco-friendly. The physicochemical parameters such as temperature, use of a dispersing agent, surfactant, and others greatly influence the quality and quantity of the synthesized NPs and ultimately affect the material’s properties. Scientists worldwide are trying to synthesize NPs and are devising methods that are easy to apply, eco-friendly, and economical. Among such strategies is the biogenic method, where plants are used as the source of reducing and capping agents. In this review, we intend to debate different strategies of AgNP synthesis. Although, different preparation strategies are in use to synthesize AgNPs such as electron irradiation, optical device ablation, chemical reduction, organic procedures, and photochemical methods. However, biogenic processes are preferably used, as they are environment-friendly and economical. The review covers a comprehensive discussion on the biological activities of AgNPs, such as antimicrobial, anticancer anti-inflammatory, and anti-angiogenic potentials of AgNPs. The use of AgNPs in water treatment and disinfection has also been discussed in detail.

Novel green synthesis and characterization of a chemotherapeutic supplement by silver nanoparticles containing Berberis thunbergii leaf for the treatment of human pancreatic cancer

In recent years, silver nanoparticles have been used as modern chemotherapeutic drugs to treat several cancers such as pancreatic, breast, prostate, and blood cancers. No previous reports demonstrated the in vitro anti-human pancreatic cancer effects of the novel chemotherapeutic drug formulated by silver nanoparticles containing Berberis thunbergii leaf (AgNPs). The synthesized AgNPs were characterized using different techniques including UV-vis. and FT-IR spectroscopy, X-ray diffraction, scanning electron microscopy (SEM), and TEM. All techniques approved the synthesized silver nanoparticles. The SEM and TEM exhibited a uniform spherical morphology and an average size of about 15 nm for the biosynthesized nanoparticles, respectively. The 4-(dimethylamino)benzaldehyde,2,2-diphenyl-1- pikrilhydrazil (DPPH) test revealed similar antioxidant potentials for B. thunbergii leaf aqueous extract, AgNPs, and butylated hydroxytoluene. AgNPs inhibited half of the DPPH molecules in the concentration of 108 μg/mL. To survey the anti-human pancreatic cancer activities of AgNO₃ , B. thunbergii leaf aqueous extract, and AgNPs, 3-(4,5-dimethylthiazol-2-yl)-2,5-diphenyl-2H-tetrazolium bromide (MTT) assay was used on common human pancreatic cancer cell lines. AgNPs had very low cell viability and anti-human pancreatic cancer effects dose-dependently against PANC-1, AsPC-1, and MIA PaCa-2. The IC50 values of the AgNPs were 259, 268, and 141 μg/mL against PANC-1, AsPC-1, and MIA PaCa-2 cell lines, respectively. It is thought that the AgNPs obtained can be used as an anticancer drug for the diagnosis of pancreatic cancer in humans after acceptance of the above findings in clinical study trials.

Fabrication of silver nanoparticles/gelatin hydrogel system for bone regeneration and fracture treatment

The present work aims to examine the effect of gelatin on the stabilization of silver nanoparticles (AgNPs) and their use in healing the bone fracture. AgNPs-loaded Gel hydrogels (AgNPs/Gel) were fabricated under sunlight using gelatin (Gel) as stabilizing agent. The characterization of the synthesized hydrogels was performed with the help of techniques such as UV-visible spectroscopy (UV-Vis) and high-resolution transmission electron microscopy (HR-TEM). Furthermore, the results of cell cytotoxicity confirmed that the AgNPs/Gel hydrogels are nonhazardous to osteoblasts. The outcome of cell fixation with AgNPs/Gel hydrogels after an incubation period of five days exposed the improved survival and spreading of osteoblasts cells on the prepared AgNPs/Gel hydrogels. Moreover, the AgNPs/Gel hydrogel nanostructures displayed their ability in modulating bone fracture healing, which suggests their potential use in nursing care.

Synthesis, Characterization, and Antimicrobial Properties of Sparfloxacin-Mediated Noble Metal Nanoparticles

The aim of the current research finding was to synthesize, characterize and antibacterial evaluation of sparfloxacin-mediated noble metal nanoparticles. Noble metal [silver (Ag), and gold (Au)] nanoparticles (NPs), mediated with fluoroquinolone, an anti-bacterial drug [Sparfloxacin, (Sp)], was synthesized by a facile and convenient procedure. Formulated Ag-Sp NPs, and Au-Sp NPs exhibited stability against variation in pH, NaCl solution, temperature, and time. The structural topographies of Ag-Sp, and Au-Sp NPs were determined by fourier transform infrared spectroscopy (FTIR), UV-visible spectroscopy (UV-Vis), scanning electron microscopy (SEM) atomic force microscopy (AFM), and energy dispersive X-ray (EDX). UV-Vis revealed the formulation of NPs by showing typical surface Plasmon absorption maxima at 410 nm for Ag-Sp NPs and 555 nm for Au-Sp NPs. The AFM and SEM analysis ascertained stable mono dispersed Ag-Sp NPs and Au-Sp NPs in the size range of 40-50 nm, and 70-80 nm, respectively. Ag-Sp, and Au-Sp NPs exhibited antibacterial traits against Bacillus subtilis, Staphylococcus aureus, and Klebsiella pneumonia, showing a zone of inhibition (ZOI) ranging from 20±0.98 mm to 24±0.94 mm (Ag-Sp NPs), and 22±0.79 mm to 26±0.92 mm (Au-Sp NPs) at dose of 3 mg/mL.

Biogenically proficient synthesis and characterization of silver nanoparticles employing marine procured fungi Aspergillus brunneoviolaceus along with their antibacterial and antioxidative potency

OBJECTIVES

To assess the extracellular synthesis of silver nanoparticles using marine derived fungi Aspergillus brunneoviolaceus with their antibacterial and antioxidant activities.

RESULTS

The biosynthesis of silver nanoparticles was estimated by the change in color from light yellow to dark brown within 36 h as the reaction progressed. UV-Visible spectroscopy exhibited its stability at 411 nm; ATR-FTIR spectroscopy depicted the functional group responsible for its production; X-Ray Diffraction denoted its crystalline FCC structure resembling the peaks in XRD pattern, corresponding to [111], [200], [220], [311] and [222] planes; TEM imaging revealed its spherical morphology with the particle size ranging from 0.72 to 15.21 nm and Tauc's plot analysis that disclosed its band gap energy as 2.44 eV that manifested the potential of AgNPs to be semiconductors. The characterization data henceforth, confirmed the efficient production of silver nanoparticles. The biosynthesized AgNPs expressed strong antibacterial activity against two Gram-positive and three Gram-negative bacteria. They also proved to possess higher antioxidative potentials by showing their potent radical scavenging activity against DPPH (2, 2-diphenyl-1-picrylhydrazyl).

CONCLUSIONS

The study unfolds the prospect for further utilization of this mycogenically synthesized AgNPs as antibacterial, antioxidative and anticancer agents.

Eco-friendly synthesis of silver nanoparticles from the whole plant of Cleome viscosa and evaluation of their characterization, antibacterial, antioxidant and antidiabetic properties

The current research is to develop an easy and eco-friendly method for the synthesis of three different concentrations of silver nanoparticles (1mMCvAgNPs, 2mMCvAgNPs and 3mMCvAgNPs) using aqueous whole plant extract of Cleome viscosa and to evaluate their antibacterial, antioxidant and antidiabetic properties. CvAgNPs were characterized by Using UV–vis spectrophotometer, X-ray diffraction (XRD), Fourier transform infrared spectroscopy (FT-IR), scanning electron microscope (SEM) and transmission electron microscope (TEM). The formation of CvAgNPs was confirmed by the observation of band between 250 nm to 600 nm UV–vis spectrum. The crystalline structure of CvAgNPs with a face-centered cubic (FCC) was confirmed by XRD. The responsible phytochemicals for the reduction and capping material of CvAgNPs were observed with FT-IR. The SEM analysis confirmed the size and shapes of CvAgNPs. The CvAgNPs have shown the rich content of total phenolic and total flavonoid components. The CvAgNPs have shown significant antibacterial activity on multi drug resistance Gram-negative and Gram-positive bacteria and also have shown significant strong antioxidant activities (DPPH, ABTS, H₂O₂ scavenging, Phosphomolybdenum assay and reducing power). The inhibitory action of CvAgNPs on α-glucosidase and α-amylase was stronger than the inhibitory action of acarbose. To best of our knowledge, this is the first attempt on the synthesis of AgNPs using C. viscosa whole plant aqueous extract. The synthesized CvAgNPs exhibited good antimicrobial, antioxidant and antidiabetic properties. Hence, to validate our results, the in vivo studies at the molecular level are needed to develop Cleome viscosa as an antibacterial, antioxidant and anti-diabetic agent.

Antibacterial and cytotoxic activities of cerium oxide nanoparticles prepared by laser ablation in liquid

In this work, we have prepared cerium oxide (CeO₂) nanoparticles (NPs) by laser ablation in water at different laser energies. The structural and optical properties of synthesized nanoparticles were characterized by X-ray diffraction (XRD), scanning electron microscope (SEM), Raman spectroscopy, energy dispersive X-ray (EDX), and UV-Vis absorption. XRD results confirmed that the synthesized cerium oxide NPs were crystalline in nature with cubic structure. SEM investigations show that the nanoparticles having a spherical shape with diameter ranged from 26 to 37 nm depending on the laser energy. The antibacterial activity and minimal inhibition concentration of synthesized CeO₂ NPs against Escherichia coli, Staphylococcus aureus, and Pseudomonas aeruginosa were examined. Bacterial adhesion test of cerium oxide NPs was also determined under different incubation temperatures. Cytotoxicity of CeO₂ NP effect against the human throat cancer was studied. The cytotoxicity effect of CeO₂ NPs synthesized at 160 mJ on the cancer cells caused a free radical releasing which causing oxidative stress. The cytotoxicity effects of ceria NPs against human throat cancer (RD rhabdomyosarcoma cell line) and mouse fibroblast L cell (L20B cell line) growth were 33% and 13%, respectively.

Synthesis of Silver Nanoparticles Using Odontosoria chinensis (L.) J. Sm. and Evaluation of their Biological Potentials

The present study was aimed to synthesize silver nanoparticles (AgNPs) from the aqueous extracts of Odontosoria chinensis (L.) J. Sm. and the synthesized AgNPs were examined for their biopotentials. The Odontosoria chinensis extracts were added to 1 mM AgNO₃ solution with different ratios viz., 0.5: 9.5, 1:9, 1.5: 8.5 and 2: 8 ratios for the reduction of Ag ions. After reduction, the AgNPs of Odontosoria chinensis were analyzed spectroscopically for further confirmation. The synthesized AgNPs of Odontosoria chinensis were characterized by pH, ultra violet-visible spectroscopy (UV-Vis), Fourier transform-infra red spectroscopy (FT-IR), scanning electron microscopy-energy dispersive X-ray analysis (SEM-EDAX) and X-Ray diffraction (XRD). The time taken for the complete reduction of Silver (Ag) in solution to nanoparticle was 10 min. The O. chinensis aqueous extracts mediated silver nanoparticles showed a broad peak with distinct absorption at around 400-420 nm and confirmed the silver nanoparticle formation. FT-IR results also confirmed the existence of organic materials in the silver nanoparticles of O. chinensis. The EDX spectra of AgNPs of O. chinenesis revealed the occurrence of a strong Ag peak. The synthesis of AgNPs of O. chinenesis was confirmed with the existence of a peak at 46.228°. The toxic potential of AgNPs of O. chinenesis showed varied percentage mortality with the LC₅₀ values of 134.68 μL/ 50 mL and 76.5 μL/50 mL, respectively. The anti-inflammatory and anti-diabetic activities of aqueous and AgNPs of O. chinenesis were statistically significant at p < 0.05 level. Conclusion: The results demonstrated the toxicity, anti-diabetic and anti-inflammatory potential of the studied AgNPs. The synthesized nanoparticles of Odontosoria chinensis could be tested as an alternative to anticancer, anti-diabetic and anti-inflammatory drugs.

Screening bioactivities of Caesalpinia pulcherrima L. swartz and cytotoxicity of extract synthesized silver nanoparticles on HCT116 cell line

The extract of Caesalpinia pulcherrima (C. pulcherrima) is one of the common herbal drugs which have a key role in treating pyretic, microbial infections, cancer and for several other traditional systems of treatment. In our present work, we demonstrate the bioactivities of extracts and cytotoxicity of synthesized silver nanoparticles on HCT116 cell line. The qualitative phytochemical tests indicated the presence of some adequately required metabolites as follows; the total phenolic content in the aqueous extract contains a higher amount of phenolic compounds (815 ± 0.013 μgmg^-1). The DPPH quenching activity of the aqueous extract showed an IC₅₀ value of 18.7 μg which was equivalent to the IC₅₀ value of ascorbic acid (15 μg) and methanolic extract (51 μg). The test extracts showed 4.6% haemolytic activity that attributes to its protective and non-toxic nature. The zone of inhibition of aqueous extract shown against the growth of E.coli was 25 mm. Further, silver nanoparticles synthesis was carried out with the extract and was characterized by X-ray diffraction, particle size analyzer, zeta potential, TEM- EDAX and UV spectroscopy. XRD analysis indicated the crystalline nature of silver nanoparticles with a face-centered cubic structure. The data obtained from the particle size analyzer demonstrated as 155.4 nm of the size of the synthesized silver nanoparticles. The values of zeta potential (-23.4 mV) revealed that the nanoparticles were extremely stable in colloidal form. SEM indicated the spherical shape of silver nanoparticles with the size range between 177.9 nm to 251.1 nm. Beside the efficient bioactivities, the synthesized C. pulcherrima silver nanoparticles showed significant cytotoxicity effect of 77.5% on a human colon cancer cell line. Therefore, along with antioxidant, antibacterial, haemolytic activity; C. pulcherrima also accomplished satisfactory cytotoxic property in anticancer mechanism as proven by this study.