Facile synthesis of biocompatible gold nanoparticles from Vites vinefera and its cellular internalization against HBL-100 cells

Wound healing effects of biogenic gold nanoparticles synthesized using red wine extracts

Gold nanoparticles (AuNPs) were synthesized using three red wine extracts (RW-Es); by varying temperature, pH, concentrations of RW-Es and gold salt. The RW-AuNPs were characterized by UV-vis, transmission electron microscopy (TEM), dynamic light scattering (DLS), and the Fourier Transform Infra-red Spectroscopy (FT-IR). Their stability was evaluated in water, foetal bovine serum (FBS), phosphate-buffered saline (PBS), and Dulbecco's Modified Eagle Medium (DMEM) by UV-Vis. The effect of the RW-Es and RW-AuNPs on KMST-6 cell cell viability was evaluated by MTT assay; and their wound healing effects were monitored by scratch assay. RW-AuNPs synthesis was observed by colour change, and confirmed by UV-Vis spectrum, with an absorption peak around 550 nm. The hydrodynamic sizes of the RW-AuNPs ranged between 10 and 100 nm. Polyphenols, carboxylic acids, and amino acids are some of functional groups in the RW-Es that were involved in the reduction of RW-AuNPs. The RW-AuNPs were stable in test solutions and showed no cytotoxicity to the KMST-6 cells up to 72 h. AuNPs synthesized from Pinotage and Cabernet Sauvignon enhanced proliferation of KMST-6 cells and showed potential as wound healing agents. Further studies are required to investigate the molecular mechanisms involved in the potential wound-healing effect of the RW-AuNPs.

Biogenic green metal nano systems as efficient anti-cancer agents

Metal/metal oxide nano systems (M-NSs) of tunable and manipulative properties are emerging suitable for cancer management via immunity development, early-stage diagnosis, nanotherapeutics, and targeted drug delivery systems. However, noticeable toxicity, off-targeted actions, lacking biocompatibility, and being expensive limit their acceptability. Moreover, involving high energy (top-down routes) and hazardous chemicals (bottom-up chemical routes) is altering human cycle. To manage such challenges, biomass (plants, microbes, animals) and green chemistry-based M-NSs due to scalability, affordability, are cellular, tissue, and organ acceptability are emerging as desired biogenic M-NSs for cancer management with enhanced features. The state-of-art and perspective of green metal/metal oxide nano systems (GM-NSs) as an efficient anti-cancer agent including, imaging, immunity building elements, site-specific drug delivery, and therapeutics developments are highlighted in this review critically. It is expected that this report will serve as guideline for design and develop high-performance GM-NSs for establishing them as next-generation anti-cancer agent capable to manage cancer in personalized manner.

Green synthesis of metalloid nanoparticles and its biological applications: A review

Synthesis of metalloid nanoparticles using biological-based fabrication has become an efficient alternative surpassing the existing physical and chemical approaches because there is a need for developing safer, more reliable, cleaner, and more eco-friendly methods for their preparation. Over the last few years, the biosynthesis of metalloid nanoparticles using biological materials has received increased attention due to its pharmaceutical, biomedical, and environmental applications. Biosynthesis using bacterial, fungal, and plant agents has appeared as a faster developing domain in bio-based nanotechnology globally along with other biological entities, thus posing as an option for conventional physical as well as chemical methods. These agents can efficiently produce environment-friendly nanoparticles with the desired composition, morphology (shape as well as size), and stability, along with homogeneity. Besides this, metalloid nanoparticles possess various applications like antibacterial by damaging bacterial cell membranes, anticancer due to damaging tumour sites, targeted drug delivery, drug testing, and diagnostic roles. This review summarizes the various studies associated with the biosynthesis of metalloid particles, namely, tellurium, arsenic, silicon, boron, and antimony, along with their therapeutic, pharmaceutical and environmental applications.

Neuroprotective Effect of Gold Nanoparticles and Alpha-Lipoic Acid Mixture against Radiation-Induced Brain Damage in Rats

The current study aims to evaluate the possible neuroprotective impact of gold nanoparticles (AuNPs) and an alpha-lipoic acid (ALA) mixture against brain damage in irradiated rats. AuNPs were synthesized and characterized using different techniques. Then, a preliminary investigation was carried out to determine the neuroprotective dose of AuNPs, where three single doses (500, 1000, and 1500 µg/kg) were orally administrated to male Wistar rats, one hour before being exposed to a single dose of 7Gy gamma radiation. One day following irradiation, the estimation of oxidative stress biomarkers (malondialdehyde, MDA; glutathione peroxidase, GPX), DNA fragmentation, and histopathological alterations were performed in brain cortical and hippocampal tissues in both normal and irradiated rats. The chosen neuroprotective dose of AuNPs (1000 µg/kg) was processed with ALA (100 mg/kg) to prepare the AuNPs-ALA mixture. The acute neuroprotective effect of AuNPs-ALA in irradiated rats was determined against valproic acid as a neuroprotective centrally acting reference drug. All drugs were orally administered one hour before the 7Gy-gamma irradiation. One day following irradiation, animals were sacrificed and exposed to examinations such as those of the preliminary experiment. Administration of AuNPs, ALA, and AuNPs-ALA mixture before irradiation significantly attenuated the radiation-induced oxidative stress through amelioration of MDA content and GPX activity along with alleviating DNA fragmentation and histopathological changes in both cortical and hippocampal tissues. Notably, the AuNPs-ALA mixture showed superior effect compared to that of AuNPs or ALA alone, as it mitigated oxidative stress, DNA damage, and histopathological injury collectively. Administration of AuNPs-ALA resulted in normalized MDA content, increased GPX activity, restored DNA content in the cortex and hippocampus besides only mild histopathological changes. The present data suggest that the AuNPs-ALA mixture may be considered a potential candidate for alleviating radiation-associated brain toxicity.

Green synthesis of novel stable biogenic gold nanoparticles for breast cancer therapeutics via the induction of extrinsic and intrinsic pathways

Biosynthesis of gold nanoparticles (AuNPs) using algal polysaccharides is a simple, low-cost, and an eco-friendly approach. In the current study, different concentrations of Arthospira platensis exopolysaccharides (EPS) were used to synthetize AuNPs via the reduction of gold ions. The biologically synthesized AuNPs (AuNPs1, AuNPs2, AuNPs3) were prepared in 3 different forms through the utilization of three different ratios of EPS-reducing agents. AuNPs analysis confirmed the spherical shape of the EPS-coated AuNPs. Furthermore, AuNPs prepared by EPS and l-ascorbic acid (AuNPs3) showed more stability than the AuNPs colloidal solution that was prepared using only l-ascorbic acid. Analysis of the antimicrobial effects of AuNPs showed that E. coli was the most sensitive bacterial species for AuNPs3 and AuNPs1 with inhibition percentages of 88.92 and 83.13%, respectively. Also, safety assay results revealed that AuNPs3 was the safest biogenic AuNPs for the tested noncancerous cell line. The anticancer assays of the biogenic AuNPs1, AuNPs2, and AuNPs3 against MCF-7 cell line indicated that this cell line was the most sensitive cell line to all treatments and it showed inhibition percentages of 66.2%, 57.3%, and 70.2% to the three tested AuNPs, respectively. The AuNPs also showed abilities to arrest MCF-7 cells in the S phase (77.34%) and increased the cellular population in the sub G0 phase. Gene expression analysis showed that AuNPs3 down regulated Bcl2, Ikapα, and Survivn genes in MCF-7 treated-cells. Also, transmission electron microscopy (TEM) analysis of MCf-7 cells revealed that AuNPs 3 and AuNPs2 were localized in cell vacuoles, cytoplasm, and perinuclear region.

The “End Life” of the Grape Pomace Waste Become the New Beginning: The Development of a Virtuous Cycle for the Green Synthesis of Gold Nanoparticles and Removal of Emerging Contaminants from Water

During the last decades, the demand for processes developed according to the Circular Economy Principles has increased, searching for an alternative life for wastes. For this purpose, a one-pot green approach is exploited during this work to synthesize gold nanoparticles (AuNPs) by using grape pomace waste from Vitis vinifera. A raw aqueous extract of grape seeds, skin, and stems is used for AuNPs synthesis. UV-Vis, XPS, SEM, and ATR-FTIR spectroscopies demonstrate the main role of the extract’s polyphenolic components in stabilizing nanoparticles. XRD, DLS, and Zeta Potential analyses were used to characterize AuNPs. Moreover, the ionic strength, pH, and temperature role was investigated through the Surface Plasmon Resonance (SPR) band observation to assess AuNPs’ stability and photostability. For foreseeing the as-synthesized AuNPs’ potential use in cosmetic and biomedical fields as multifunctional platforms, their antioxidant, and skin-lightening properties were tested, together with their sunscreen ability. A preliminary in-vitro evaluation is reported about the AuNPs’ cytoprotective effects against H₂O₂ oxidative stress-induced in normal human dermal fibroblasts. Briefly, the possibility of reusing the grape pomace waste after the AuNPs synthesis as an adsorbent for the efficient removal of emergent contaminants is preliminarily discussed in the paper, further valorizing the use of waste according to a bio circular approach.

Catalytic and Medical Potential of a Phyto-Functionalized Reduced Graphene Oxide-Gold Nanocomposite Using Willow-Leaved Knotgrass

In the current study, a simple, environmentally friendly, and cost-effective reduced graphene oxide-gold nanoparticle (rGO-AuNP) nanocomposite was successfully phytosynthesized using the aqueous leaf extract of a common weed found on the Nile banks, Persicaria salicifolia, for the first time. The phytosynthesis of rGO-AuNPs was first confirmed via the color transformation from brown to black as well as throughvarious techniques such as transmission electron microscopy (TEM) and Raman spectroscopy. Two UV-vis peaks at 275 and 530 nm were observed for the nanocomposite with a typical particle size of mostly spherical AuNPs of 15-20 nm. However, other shapes were occasionally detected including rods, triangles, and rhomboids. Existing phytoconstituents such as flavonoids and glycosides in the plant extract were suggested to be responsible for the phytosynthesis of rGO-AuNPs. The excellent catalytic efficacy of rGO-AuNPs against MB degradation was confirmed, and a high antibacterial efficiency against Escherichia coli and Klebsiella pneumonia was also confirmed. Promising antioxidant performance of rGO-AuNPs was also proved. Furthermore, it was concluded that rGO-AuNPs acquired higher efficiency than AuNPs synthesized from the same plant extract in all of the studied applications.

Grape Seed Extract Assisted Synthesis of Dual-Functional Anatase TiO2 Decorated Reduced Graphene Oxide Composite for Supercapacitor Electrode Material and Visible Light Photocatalytic Degradation of Bromophenol Blue Dye

The grape extract is a potential natural reducing agent because of its high phenolic content. The extracts of seeds, skin, and pulp of grape were prepared by digestion, grinding, and soxhlet methods and used for reducing graphene oxide (GO). The reduced GO made using the soxhlet extract of grape seed (GRGO) was hydrothermally treated with titanium dioxide (TiO₂) for the synthesis of GRGO-TiO₂ nanocomposite. The X-ray diffraction (XRD), thermogravimetric analysis (TGA), Fourier transform infrared (FT-IR), UV-vis, photoluminescence, and Raman spectra studies further confirmed the formation of GRGO and the GRGO-TiO₂ hybrid. Scanning electron microscope and transmission electron microscope studies showed the decoration of spherical TiO₂ particles (<100 nm) on the few-layered GRGO sheets. The GRGO-TiO₂ hybrid was explored as a working electrode for supercapacitors and visible light photocatalyst for water decontamination. GRGO-TiO₂ showed higher specific capacitance (175 F g^-1) than GRGO (150 F g^-1) and TiO₂ (125 F g^-1) in an aqueous electrolyte. GRGO-TiO₂ exhibited 83.6% capacitance retention even after 2000 cycles, indicating the good stability of the material. Further, under visible light irradiation (λ > 400 nm), GRGO-TiO₂ showed ∼30% higher photo-oxidation of the bromophenol blue (BPB) dye than TiO₂. Also, GRGO-TiO₂ decreased the total organic carbon content of BPB from 92 to 18 ppm. Overall, the soxhlet extract of grape seed was found to be a cost-effective reducing agent for the preparation of GRGO, which is a suitable material to be used in supercapacitors and photocatalysis.

A Systematic Review of Biosynthesized Metallic Nanoparticles as a Promising Anti-Cancer-Strategy

Cancer is one of the foremost causes of death worldwide. Cancer develops because of mutation in genes that regulate normal cell cycle and cell division, thereby resulting in uncontrolled division and proliferation of cells. Various drugs have been used to treat cancer thus far; however, conventional chemotherapeutic drugs have lower bioavailability, rapid renal clearance, unequal delivery, and severe side effects. In the recent years, nanotechnology has flourished rapidly and has a multitude of applications in the biomedical field. Bio-mediated nanoparticles (NPs) are cost effective, safe, and biocompatible and have got substantial attention from researchers around the globe. Due to their safe profile and fewer side effects, these nanoscale materials offer a promising cure for cancer. Currently, various metallic NPs have been designed to cure or diagnose cancer; among these, silver (Ag), gold (Au), zinc (Zn) and copper (Cu) are the leading anti-cancer NPs. The anticancer potential of these NPs is attributed to the production of reactive oxygen species (ROS) in cellular compartments that eventually leads to activation of autophagic, apoptotic and necrotic death pathways. In this review, we summarized the recent advancements in the biosynthesis of Ag, Au, Zn and Cu NPs with emphasis on their mechanism of action. Moreover, nanotoxicity, as well as the future prospects and opportunities of nano-therapeutics, are also highlighted.

Emerging Antineoplastic Biogenic Gold Nanomaterials for Breast Cancer Therapeutics: A Systematic Review

Breast cancer remains as a concerning global health issue, being the second leading cause of cancer deaths among women in the United States (US) in 2019. Therefore, there is an urgent and substantial need to explore novel strategies to combat breast cancer. A potential solution may come from the use of cancer nanotechnology, an innovative field of study which investigates the potential of nanomaterials for cancer diagnosis, therapy, and theranostic applications. Consequently, the theranostic functionality of cancer nanotechnology has been gaining much attention between scientists during the past few years and is growing exponentially. The use of biosynthesized gold nanoparticles (AuNPs) has been explored as an efficient mechanism for the treatment of breast cancer. The present study supposed a global systematic review to evaluate the effectiveness of biogenic AuNPs for the treatment of breast cancer and their anticancer molecular mechanisms through in vitro studies. Online electronic databases, including Cochrane, PubMed, Scopus, Web of Science, Science Direct, ProQuest, and Embase, were searched for the articles published up to July 16, 2019. Our findings revealed that plant-mediated synthesis was the most common approach for the generation of AuNPs. Most of the studies reported spherical or nearly spherical-shaped AuNPs with a mean diameter less than 100 nm in size. A significantly larger cytotoxicity was observed when the biogenic AuNPs were tested towards breast cancer cells compared to healthy cells. Moreover, biogenic AuNPs demonstrated significant synergistic activity in combination with other anticancer drugs through in vitro studies. Although we provided strong and comprehensive preliminary in vitro data, further in vivo investigations are required to show the reliability and efficacy of these NPs in animal models.

Effect of TiO2 and Fe doped TiO2 nanoparticles on mitochondrial membrane potential in HBL-100 cells

Titanium dioxide (TiO₂) nanoparticles (NPs) have made unbelievable progress in the field of nanotechnology and biomedical research. The proper toxicological assessment of TiO₂ NPs and the reduction of its cytotoxicity need to be addressed. Fe doping in TiO₂ has been investigated to reduce the toxic effects of TiO₂ NPs. Fe doped TiO₂ powder samples were synthesized by sol-gel methods. The prepared samples were characterized by x-ray diffractometer (XRD), transmission electron microscope (TEM), and Raman spectroscopy to study their structure, morphology, and molecular conformation. XRD results revealed the coexistence of anatase (A) and rutile (R) phases of TiO₂. The A-R transformation was observed with an increase in Fe doping along with the formation of α-Fe₂O₃ phase. TEM showed changes in morphology from spherical nanoparticles to elongated rod-shaped nanostructures with increasing Fe content. Shape variation of TiO₂ nanoparticles after incorporation of Fe is a key reason behind the toxicity reduction. The authors observed that the toxicity of TiO₂ nanoparticles was rescued upon Fe incorporation. The effect of NPs on the mitochondrial membrane potential (MMP) was assessed using flow cytometry. The MMP (%) decreased in TiO₂ treated cells and increased by 1% Fe doped TiO₂ NPs treated cells. Confocal imaging revealed the presence of functional mitochondria upon the exposure of Fe doped TiO₂ NPs. The goal of the present study was to decrease the toxic effects induced by TiO₂ NPs on mitochondrial potential and its prevention by Fe doping.

Two-Dimensional Infrared Spectroscopy Reveals Molecular Self-Assembly on the Surface of Silver Nanoparticles

The conformation of molecules, peptides, and proteins, self-assembled into structured monolayers on the surface of metal nanoparticles (NPs), can strongly affect their properties and use in chemical or nanobiomedical applications. Elucidating molecular conformations on the NP surface is highly challenging, and the microscopic details mostly remain elusive. Using polarization-selective third-order two-dimensional ultrafast infrared spectroscopy, we revealed the highly ordered intermolecular structure of γ-tripeptide glutathione on the surface of silver NPs in aqueous solution. Glutathione is an antioxidant thiol abundant in living cells; it is extensively used in NP chemistry and related research. We identified conditions where the interaction of glutathione with the NP surface facilitates formation of a β-sheet-like structure enclosing the NPs. A spectroscopic signature associated with the assembly of β-sheets into an amyloid fibril-like structure was also observed. Remarkably, the interaction with the metal surface promotes formation of a fibril-like structure by a small peptide involving only two amino acids.

Biological synthesis of metallic nanoparticles (MNPs) by plants and microbes: their cellular uptake, biocompatibility, and biomedical applications

Metallic nanoparticles (MNPs) with their diverse physical and chemical properties have been applied in various biomedical domains. The increasing demand for MNPs has attracted researchers to develop straightforward, inexpensive, simple, and eco-friendly processes for the enhanced production of MNPs. To discover new biomedical applications first requires knowledge of the interactions of MNPs with target cells. This review focuses on plant and microbial synthesis of biological MNPs, their cellular uptake, biocompatibility, any biological consequences such as cytotoxicity, and biomedical applications. We highlighted the involvement of biomolecules in capping and stabilization of MNPs and the effect of physicochemical parameters particularly the pH on the synthesis of MNPs. Recently achieved milestones to understand the role of synthetic biology (SynBiol) in the synthesis of tailored MNPs are also discussed.

Impact of gold nanoparticles shape on their cytotoxicity against human osteoblast and osteosarcoma in in vitro model. Evaluation of the safety of use and anti-cancer potential

Due to development of nanotechnology and gold nanoparticles (AuNPs) increasing use in different areas of medicine, especially in oncology, better understanding of their potential cytotoxicity is necessary to protect patients safety. Shape and size of AuNPs is an important modulator of their cytotoxicity. Therefore, we investigated the cytotoxicity of AuNPs rods (≈39 nm length, 18 nm width), AuNPs stars (≈ 215 nm) and AuNPs spheres (≈ 6.3 nm) against human fetal osteoblast (hFOB 1.19), osteosarcoma (143B, MG63) and pancreatic duct cell (hTERT-HPNE) lines by MTT and neutral-red uptake assay. Moreover, influence of AuNPs on level of proapoptotic protein (Bax) and anti-apoptotic protein (Bcl-2) was measured by western blot. Cellular uptake of nanoparticles and ultrastructure changes were examined by transmission electron microscopy (TEM). In the present study we have proven that AuNPs stars are the most cytotoxic against human cells. We observed that cancer cells are more susceptible to AuNPs cytotoxic effect. Furthermore, AuNPs rods and AuNPs stars caused increased expression of Bax and decreased expression of Bcl-2 protein in osteosarcoma cells. We found that AuNPs penetrated through the cell membrane and caused ultrastructural changes. Our results clearly demonstrated that the cytotoxicity of AuNPs was shape-dependent. AuNPs stars with the highest anti-cancer potential were also the most cytotoxic type of tested NPs, whereas AuNPs spheres which appears to be the safest one had small anti-cancer potential.

Nanoparticles Biosynthesized by Fungi and Yeast: A Review of Their Preparation, Properties, and Medical Applications

In the field of nanotechnology, the use of various biological units instead of toxic chemicals for the reduction and stabilization of nanoparticles, has received extensive attention. Among the many possible bio resources, biologically active products from fungi and yeast represent excellent scaffolds for this purpose. Since fungi and yeast are very effective secretors of extracellular enzymes and number of species grow fast and therefore culturing and keeping them in the laboratory are very simple. They are able to produce metal nanoparticles and nanostructure via reducing enzyme intracellularly or extracellularly. The focus of this review is the application of fungi and yeast in the green synthesis of inorganic nanoparticles. Meanwhile the domain of biosynthesized nanoparticles is somewhat novel; the innovative uses in nano medicine in different areas including the delivery of drug, cancer therapy, antibacterial, biosensors, and MRI and medical imaging are reviewed. The proposed signaling pathways of nanoparticles induced apoptosis in cancerous cells and anti-angiogenesis effects also are reviewed. In this article, we provide a short summary of the present study universally on the utilization of eukaryotes like yeast and fungi in the biosynthesis of nanoparticles (NPs) and their uses.

Green synthesis of therapeutic nanoparticles: an expanding horizon

Nanotechnology continues to achieve tremendous awards in therapeutics, but the economical and ecofriendly production of nanoparticles (NPs) is still in infancy, simply due to the nanotoxicity, unprecedented health hazards and scale up issues. Green nanotechnology was introduced in the quest to mitigate such risks by utilizing natural resources as biological tool for NP synthesis. The key advantages offered by green approach include lower capital and operating expenses, reduced environmental impacts, superior biocompatibility and higher stability. In this review, we shed light on the biosynthesis of therapeutic NPs along with their numerous biomedical applications. Toxicity aspects of NPs and the impact of green approach on it, is also discussed briefly.

Applications of biosynthesized metallic nanoparticles - a review

We present a comprehensive review of the applications of biosynthesized metallic nanoparticles (NPs). The biosynthesis of metallic NPs is the subject of a number of recent reviews, which focus on the various "bottom-up" biofabrication methods and characterization of the final products. Numerous applications exploit the advantages of biosynthesis over chemical or physical NP syntheses, including lower capital and operating expenses, reduced environmental impacts, and superior biocompatibility and stability of the NP products. The key applications reviewed here include biomedical applications, especially antimicrobial applications, but also imaging applications, catalytic applications such as reduction of environmental contaminants, and electrochemical applications including sensing. The discussion of each application is augmented with a critical review of the potential for continued development.