Eco-friendly Gold Nanoparticles Research Articles

Anisotropic Gold Nanoparticles Synthesized using Litchi chinensis Leaf Extract and their Effect on Breast Cancer

For its medicinal potential, especially in cancer therapy, eco-friendly gold nanoparticles (GNPs) have gained a lot of interest. This investigation used Litchi chinensis leaf extract (LLE) as a reducing agent for the one-step synthesis of regulated-size GNPs. Fourier transform infrared (FTIR) spectrum shows that the bio-molecules act as capping and reducing agents. The formation of GNPs has been confirmed using UV-vis absorption spectra. Effect of various synthesized parameters, i.e., reaction time (5–120 minutes), temperature (25–100°C), solvent quantity (5–45 μL), metal ion concentration (0.25–2 mM) and pH (2–10) has been studied. The size, distribution, and morphology (anisotropic) have been studied using field emission scanning electron microscopy (FESEM) and dynamic light scattering (DLS) techniques in the range of 10 to 70 nm. X-Ray diffraction (XRD) reveals that the particles were crystalline and had face-centered cubic (FCC) structure, and transmission electron microscopy (TEM) images revealed anisotropic morphology (spherical, hexagonal, and triangular). In-vitro studies of GNPs on breast cancer cell lines show cytotoxicity with cellular structural alterations and caused DNA damage without the micronuclei formation.

In-Vitro Anti-Hypertensive, Antifungal and Antioxidant Properties of Green Synthesized Gold Nanoparticles and not Nano articlesfrom Strophanthus Hispidus Leaf Aqueous Extract

Nanotechnology, the science of manipulating matter at atomic level has paved way for many innovative ideas in all areas. In this research, the green synthesis of gold nanoparticles from Strophanthus hispidus and some of its biomedical applications were evaluated. The aqueous extract of Strophanthus hispidus was employed in the mediation of gold nanoparticles, the reaction resulted in deep purple colour colloidal suspension formation after 15 minutes of photo-activation. The colloidal suspension was subjected to characterization using UV-Vis spectroscopy, FTIR, EDX and TEM. The UV-Vis spectrum of the AuNPs displayed strong peak at 552 nm. The FTIR showed broad peaks at 3417.98, 2918.40, 2359.02, 2000.25, 1766.85, 1622.19, 1384.94 and 1097.53 cm-1 which are attributed to the involvement of sugar, alkaloids and proteins in the AuNPs synthesis and stabilization. Gold was the prominent metal observed in the EDX analysis while the TEM micrograph showed spherical particles whose sizes are between 10.90 and 34.63 50nm.The AuNPs showed antifungal activities of 87.6, 70.1, 72.5, 82.8 and 51.8% against Aspergillus flavus, Aspergillus niger, Fusarium poae, Fusarium solani and Penicillium avenatum respectively at 50 µl /ml. The AuNPs showed significant antioxidant properties of 90.96, 88.09, 85.23 and 84.47% at 50, 100, 150 and 200µl/ml against DPPH. The AuNPs showed a significant angiotensin converting enzyme (ACE) inhibitory activities of 60.88 ± 3.100% at concentration of 50µg/ml. Conclusively, this study has established the relevance of Strophanthus hispidus leaf aqueous extract in the bio-fabrication of eco-friendly gold nanoparticles. The nanoparticles showed significant antifungal properties which could be useful in the production of eco-friendly fungicides, and also its antihypertensive properties have proven its drug improvement potentials, also the antioxidant activity of the gold nanoparticles could be useful in combating against oxidative stress.

Facile, low-cost and rapid phytosynthesis of stable and eco-friendly gold nanoparticles using green walnut shell and study of their anticancer potential

Facile, low-cost and rapid phytosynthesis of stable and eco-friendly gold nanoparticles using green walnut shell and study of their anticancer potential

Bioassisted Synthesis of Gold Nanoparticles from Saccharomonospora glauca: Toxicity and Biocompatibility Study

Bionanosynthesis is an important aspect in the rapidly growing field of nanotechnology that provides a good functional material of biological interest. In the present study, bioassisted synthesis of gold nanoparticles (GNPs) was carried out using Saccharomonospora glauca, rare actinomycetes isolated from soil and were tested for haemocompatibility and cytotoxicity against NIH3T3, HT-29, and Hep 2 cells. Bioreduction was monitored by using UV-visible spectroscopy and characterised by FTIR, XRD, SEM, DLS and zeta potential. XRD confirmed the crystalline nature of the synthesised GNPs. The average particle size obtained by SEM and DLS was found to be 30 nm with spherical in shape. The synthesised GNPs showed good cytotoxic activity against cancer cell lines HT-29 and Hep 2 with an IC-50 value of 49.8 μg/ml and 96.8 μg/ml respectively and least toxicity for normal cell lines NIH3T3. This was further confirmed by staining the cells with AO and PI dual staining for apoptosis detection. The synthesised GNPs showed excellent biocompatibility for human blood without haemolysis. The work reports for the first time the synthesis of simple and eco-friendly GNPs from Saccharomonospora glauca showing excellent biocompatibility and good toxicity for cancer cells with mild toxicity for normal cell lines that can be implemented for biomedicine.

Biomolecules from snail mucus (Helix aspersa) conjugated gold nanoparticles, exhibiting potential wound healing and anti-inflammatory activity.

In this work, for the first time, snail slime from garden snails "Helix Aspersa Müller", has been used to induce the formation of eco-friendly gold nanoparticles (AuNPs-SS) suitable for biomedical applications. An AuNPs-SS comprehensive investigation was performed and AuNPs with an average particle size of 14 ± 6 nm were observed, stabilized by a slime snail-based organic layer. Indeed, as recognized in high-resolution MALDI-MS analyses, and corroborated by FESEM, UV-Vis, ATR-FTIR, and XPS results, it was possible to assess the main presence of peptides and amino acids as the main components of the slime, that, combined with the AuNPs confers on them interesting properties. More specifically, we tested, in vitro, the AuNPs-SS safety in human keratinocytes and their potential effect on wound healing as well as their anti-inflammatory properties in murine macrophages. Moreover, the AuNPs-SS treatment resulted in a significant increase of the urokinase-type plasminogen activator receptor (uPAR), essential for keratinocyte adhesion, spreading, and migration, together with the reduction of LPS-induced IL1-β and IL-6 cytokine levels, and completely abrogated the synthesis of inducible nitric oxide synthase (iNOS).

Green synthesis of gold nanoparticles: Preparation, characterization, cytotoxicity, and anti-bacterial activities

Abstract Synthesis of nanostructures using green chemistry has been popular owing to the exciting properties and innovative applications of these nanostructures. Novel, cost-effective, and eco-friendly gold nanoparticles (Au NPs) were synthesized using a mix of Olea europaea (OE) fruit extract and Acacia nilotica (AN) husk extract. The synthesized Au NPs were characterized by UV–visible spectroscopy, and the average NP size (44.96 nm) was measured by a Zetasizer. A more detailed characterization was performed using Fourier transform infrared spectroscopy, scanning, and transmission electron microscopy and electron microscopy with energy dispersive spectroscopy. The cytotoxicity of the synthesized OEAN Au NPs was evaluated using an MTT assay on breast (MCF-7), colon (TCT-116), and hepatocellular (HCepG-2) carcinoma cells. The antibacterial activity of the synthesized OEAN Au NPs was investigated using a disc diffusion method. The synthesized Au NPs exhibited moderate antibacterial activity against the bacterial strains used and profound anticancer activity against different cell lines used.

Design of Eco-Friendly Gold Nanoparticles for Cancer Treatment.

Gold nanoparticles (GNPs) have emerged as a potential scaffold for a wide range of biomedical applications such as biosensing, drug delivery, and imaging. However, the toxicity of nanoparticles remains a challenge for using them in biological system. The morphology and surface chemistry of GNP can be manipulated by their method of preparation. GNP can be synthesized and functionalized by various methods. This chapter illustrates the synthesis of highly biocompatible GNP using a natural gum, i.e., xanthan gum (XG). Moreover, due to the presence of mannose moiety in XG, these XG-stabilized GNP may also act as self-targeted drug carriers for the delivery of chemotherapeutic agents/siRNA/shRNA to mannose receptor overexpressing cancer cells.

Spectroscopic study on interaction of Nymphaea nouchali leaf extract mediated bactericidal gold nanoparticles with human serum albumin

We have reported the eco-friendly gold nanoparticles (AuNPs) from 15% aqueous leaf extract of therapeutic plant Nymphaea nouchali where leaf extract acts as both reducing and stabilizing agents. The generation of AuNPs was confirmed by UV–visible spectroscopy, FTIR, FE-SEM, DLS, and the size and morphology were further confirmed via TEM analysis (average d = 54.7 nm). The existence of gold signal in EDX spectrum and measurement of zeta potential reveals a negative value (−21.7 mV) clearly indicates its stability. This synthesized AuNPs shows strong in vitro bactericidal effect against E. coli (DH5-Alpha) with 0.12 nM minimum inhibitory concentration, suggests its progress in therapeutic efficacy. The interaction of this AuNPs with human serum albumin (HSA) was investigated by UV–visible, FTIR, fluorescence, circular dichroism spectroscopies and zeta potential evaluation at 25 °C. It has been observed that the interaction mechanism is a static quenching process with the slightest change in the HSA secondary conformation because of HSA-AuNPs conjugate formation, but the primary structure remains unaffected. Negative free energy change indicates, the HSA-AuNPs formation is a thermodynamically favourable process. This analysis may offer a valuable information on the healthier antibacterial AuNPs synthesized from a medicinal plant extract.

Phytosynthesis of gold nanoparticles: Characterization, biocompatibility, and evaluation of its osteoinductive potential for application in implant dentistry

Gold nanoparticles have been extensively used in diagnostics, biomedical imaging, and drug delivery owing to simple method of synthesis and versatile surface functionalization. Present investigation aims to evaluate the osteoinductive property of Salacia chinensis (SC) mediated gold nanoparticles (GNPs) for its application in implant dentistry. The formation of GNPs was assessed initially using the visual method and characterized analytically by using UV–visible spectroscopy, Zetasizer, X-RD, ICP-AES, AFM, and TEM. Green synthesized GNPs exhibited a remarkable stability in various blood components (0.2 M histidine, 0.2 M cysteine 2% bovine serum albumin, and 2% human serum albumin) and were found to be nontoxic when evaluated for their cytocompatibility and blood compatibility using periodontal fibroblasts and erythrocytes respectively. Exposure of GNPs to MG-63 cell lines displayed increased percent cell viability (138 ± 27.4) compared to the control group (96 ± 3.7) which confirms its osteoinductive potential. Herein, it can be concluded that the stable, biocompatible and eco-friendly GNPs can be used as an effective bone inductive agent during dental implant therapy.

Changes in the concentration of avenanthramides in response to salinity stress in CBF3 transgenic oat

Oat avenanthramides have long been known to possess potential nutraceutical and therapeutical properties. The change in avenanthramides 2p, 2c and 2f concentration in four salinity tolerant transgenic oat plants containing CBF3 gene and non-transgenic control exposed to different levels of salinity stress was investigated. Determination of oat avenanthramides at the nano-scale level was performed using a well-optimized and highly sensitive sequential injection chemiluminescence (SIA-CL) method enhanced by eco-friendly gold nanoparticles biosynthesized from oat biomass extract. Under the conditions of this study, the predominant avenanthramide, which also exhibited the strongest scavenging capacity, was 2c followed by 2p and 2f. At no stress, there was no significant (p ≤ 0.05) difference between the transgenic lines and control regarding the concentrations of the three determined avenanthramides. After exposure to 250 mmol L−1 NaCl, avenanthramide 2c dramatically increased by 170.9%, 580%, 353.6%, 457.6% and 229.1% in the control and the four transgenic lines, respectively. Among the transgenic lines, Agrogle-1 maintained the highest avenanthramides concentration under all salinity levels with maximum values of 71.5 mg kg−1 for 2p, 221.0 mg kg−1 for 2c and 62.0 mg kg−1 for 2f detected at 250 mmol L−1NaCl. The results of this study demonstrated that oat avenanthramides might have a potential role in enhancing abiotic stress tolerance in oats.

Gum-Mediated Fabrication of Eco-Friendly Gold Nanoparticles Promoting Cell Division and Pollen Germination in Plant Cells

In this study we reported a simple approach for the green synthesis of gold nanoparticles (AuNPs) using the Terminalia arjuna gum extract as a source of reducing and stabilizing compounds. The fabrication of AuNPs was confirmed by UV–Vis spectroscopy, XRD and TEM. UV–Vis spectrum clearly showed the absorption peak at 520 nm, which is due to the surface Plasmon resonance on AuNPs. XRD analysis highlighted the crystalline nature of AuNPs, with face-centered cubic structure. TEM showed that spherical shape of nanoparticles, with average particles size of 10–20 nm. AuNPs did not show any inhibitory activity both on Gram-positive and Gram-negative bacteria. Furthermore, different doses of AuNPs (0, 100, 500 and 1000 µM) were tested to assess their potential impact on mitotic division and pollen germination. A treatment with 100 µM of AuNPs significantly induced both mitotic division and pollen germination. In the plant cells, the passive uptake of AuNPs through cytosol allowed them to move towards the nuclear pore complex. Subsequently, they interacted with histone protein leading to mitotic cell division and pollen germination. Overall, our study highlighted the potential of gum-fabricated AuNPs in cytogenetic, gene expression and plant tissue culture applications.

Anticancer activity of eco-friendly gold nanoparticles against lung and liver cancer cells.

Gold nanoparticles have many applications in biomedical field. Improving delivery of anticancer agents to tumors using nanoparticles is one of the most promising research arenas in the field of nanotechnology. Eco-friendly gold nanoparticles synthesis was studied using marine bacteria Enterococcus sp. The nanoparticle synthesis started at 2 h of incubation time was identified by the formation of ruby red in the reaction mixture and SPR band centered at 545 nm. XRD shows that the strong four intense peaks indicate crystalline nature of nanoparticles. Morphology of nanoparticles analyzed by TEM shows that they are mostly spherical in shape with size ranging from 6 to 13 nm. EDX supports the presence of gold in the synthesized nanoparticles. FTIR reveals the active functional groups in the culture supernatant interaction with gold nanoparticles. As a result synthesized stable gold nanoparticles show more significant anticancer activity against HepG2 and A549 cells at 100 μg concentration of nanoparticles. This synthesis approach is simple, large scaled up a new door for development of targeted anticancer activity using gold nanoparticles and is novel in biomedical applications.

Green-synthesized gold nanoparticles from Plumeria alba flower extract to augment catalytic degradation of organic dyes and inhibit bacterial growth

Bio-inspired eco-friendly gold nanoparticles were synthesized by a green method using aqueous Plumeria alba flower extract (PAFE). The use of 1% and 5% concentrations of PAFE resulted in two different sizes of P. alba gold nanoparticles, PAGNPs1 and PAGNPs2, with surface plasmon resonance (SPR) peaks at 552 and 536nm, respectively. Size-controlled formation of gold nanoparticles was indicated by the SPR shift observed with increasing concentration of PAFE. The accurate size and morphology of PAGNPs1 and PAGNPs2 were determined by transmission electron microscope (TEM) analysis is found to be 28±5.6 and 15.6±3.4nm, respectively, and those are spherical in shape. The antibacterial activity of PAGNPs1 and PAGNPs2 was tested against Escherichia coli; the small-sized PAGNPs2 exhibited better antibacterial activity with a 16-mm zone of inhibition at a concentration of 400μg/mL. Furthermore, the catalytic activity of PAGNPs1 and PAGNPs2 was analyzed on six hazardous dyes; PAGNPs2 exhibited more pronounced catalytic activity than PAGNPs1. Among all of the dyes, 4-nitrophenol was most rapidly degraded to 4-aminophenol by PAGNPs2 within 5min. The mechanism of catalysis in the presence of PAGNPs1 and PAGNPs2 can be described as an electron transfer process from donor NaBH4 to an acceptor. The facile green synthesis of such eco-friendly nanoparticles in bulk suggests this method has potential industrial applications.