An in vitro evaluation of graphene oxide reduced by <i>Ganoderma</i> spp. in human breast cancer cells (MDA-MB-231)

Gurunathan, Sangiliyandi,Han, JaeWoong,Park, Jung Hyun,Kim, Jin Hoi Dove Medical Press 2014 INTERNATIONAL JOURNAL OF NANOMEDICINE Vol.9 No.-

<P><B>Background</B></P><P>Recently, graphene and graphene-related materials have attracted much attention due their unique properties, such as their physical, chemical, and biocompatibility properties. This study aimed to determine the cytotoxic effects of graphene oxide (GO) that is reduced biologically using <I>Ganoderma</I> spp. mushroom extracts in MDA-MB-231 human breast cancer cells.</P><P><B>Methods</B></P><P>Herein, we describe a facile and green method for the reduction of GO using extracts of <I>Ganoderma</I> spp. as a reducing agent. GO was reduced without any hazardous chemicals in an aqueous solution, and the reduced GO was characterized using a range of analytical procedures. The <I>Ganoderma</I> extract (GE)-reduced GO (GE-rGO) was characterized by ultraviolet-visible absorption spectroscopy, X-ray diffraction, Fourier-transform infrared spectroscopy, X-ray photoelectron spectroscopy, dynamic light scattering, scanning electron microscopy, Raman spectroscopy, and atomic force microscopy. Furthermore, the toxicity of GE-rGO was evaluated using a sequence of assays such as cell viability, lactate dehydrogenase leakage, and reactive oxygen species generation in human breast cancer cells (MDA-MB-231).</P><P><B>Results</B></P><P>The preliminary characterization of reduction of GO was confirmed by the red-shifting of the absorption peak for GE-rGO to 265 nm from 230 nm. The size of GO and GE-rGO was found to be 1,880 and 3,200 nm, respectively. X-ray diffraction results confirmed that reduction processes of GO and the processes of removing intercalated water molecules and the oxide groups. The surface functionalities and chemical natures of GO and GE-rGO were confirmed using Fourier-transform infrared spectroscopy and X-ray photoelectron spectroscopy. The surface morphologies of the synthesized graphene were analyzed using high-resolution scanning electron microscopy. Raman spectroscopy revealed single- and multilayer properties of GE-rGO. Atomic force microscopy images provided evidence for the formation of graphene. Furthermore, the effect of GO and GE-rGO was examined using a series of assays, such as cell viability, membrane integrity, and reactive oxygen species generation, which are key molecules involved in apoptosis. The results obtained from cell viability and lactate dehydrogenase assay suggest that GO and GE-rGO cause dose-dependent toxicity in the cells. Interestingly, it was found that biologically derived GE-rGO is more toxic to cancer cells than GO.</P><P><B>Conclusion</B></P><P>We describe a simple, green, nontoxic, and cost-effective approach to producing graphene using mushroom extract as a reducing and stabilizing agent. The proposed method could enable synthesis of graphene with potential biological and biomedical applications such as in cancer and angiogenic disorders. To our knowledge, this is the first report using mushroom extract as a reducing agent for the synthesis of graphene. Mushroom extract can be used as a biocatalyst for the production of graphene.</P>

Multidimensional effects of biologically synthesized silver nanoparticles in <i>Helicobacter pylori</i> , <i>Helicobacter felis</i> , and human lung (L132) and lung carcinoma A549 cells

Gurunathan, Sangiliyandi,Jeong, Jae-Kyo,Han, Jae Woong,Zhang, Xi-Feng,Park, Jung Hyun,Kim, Jin-Hoi Springer US 2015 NANOSCALE RESEARCH LETTERS Vol.10 No.1

<P>Silver nanoparticles (AgNPs) are prominent group of nanomaterials and are recognized for their diverse applications in various health sectors. This study aimed to synthesize the AgNPs using the leaf extract of <I>Artemisia princeps</I> as a bio-reductant. Furthermore, we evaluated the multidimensional effect of the biologically synthesized AgNPs in <I>Helicobacter pylori</I>, <I>Helicobacter felis</I>, and human lung (L132) and lung carcinoma (A549) cells. UV-visible (UV–vis) spectroscopy confirmed the synthesis of AgNPs. X-ray diffraction (XRD) indicated that the AgNPs are specifically indexed to a crystal structure. The results from Fourier transform infrared spectroscopy (FTIR) indicate that biomolecules are involved in the synthesis and stabilization of AgNPs. Dynamic light scattering (DLS) studies showed the average size distribution of the particle between 10 and 40 nm, and transmission electron microscopy (TEM) confirmed that the AgNPs were significantly well separated and spherical with an average size of 20 nm. AgNPs caused dose-dependent decrease in cell viability and biofilm formation and increase in reactive oxygen species (ROS) generation and DNA fragmentation in <I>H. pylori</I> and <I>H. felis</I>. Furthermore, AgNPs induced mitochondrial-mediated apoptosis in A549 cells; conversely, AgNPs had no significant effects on L132 cells. The results from this study suggest that AgNPs could cause cell-specific apoptosis in mammalian cells. Our findings demonstrate that this environmentally friendly method for the synthesis of AgNPs and that the prepared AgNPs have multidimensional effects such as anti-bacterial and anti-biofilm activity against <I>H. pylori</I> and <I>H. felis</I> and also cytotoxic effects against human cancer cells. This report describes comprehensively the effects of AgNPs on bacteria and mammalian cells. We believe that biologically synthesized AgNPs will open a new avenue towards various biotechnological and biomedical applications in the near future.</P>

Reduced graphene oxide–silver nanoparticle nanocomposite: a potential anticancer nanotherapy

Gurunathan, Sangiliyandi,Han, Jae Woong,Park, Jung Hyun,Kim, Eunsu,Choi, Yun-Jung,Kwon, Deug-Nam,Kim, Jin-Hoi Dove Medical Press 2015 INTERNATIONAL JOURNAL OF NANOMEDICINE Vol.10 No.-

<P><B>Background</B></P><P>Graphene and graphene-based nanocomposites are used in various research areas including sensing, energy storage, and catalysis. The mechanical, thermal, electrical, and biological properties render graphene-based nanocomposites of metallic nanoparticles useful for several biomedical applications. Epithelial ovarian carcinoma is the fifth most deadly cancer in women; most tumors initially respond to chemotherapy, but eventually acquire chemoresistance. Consequently, the development of novel molecules for cancer therapy is essential. This study was designed to develop a simple, non-toxic, environmentally friendly method for the synthesis of reduced graphene oxide–silver (rGO–Ag) nanoparticle nanocomposites using <I>Tilia amurensis</I> plant extracts as reducing and stabilizing agents. The anticancer properties of rGO–Ag were evaluated in ovarian cancer cells.</P><P><B>Methods</B></P><P>The synthesized rGO–Ag nanocomposite was characterized using various analytical techniques. The anticancer properties of the rGO–Ag nanocomposite were evaluated using a series of assays such as cell viability, lactate dehydrogenase leakage, reactive oxygen species generation, cellular levels of malonaldehyde and glutathione, caspase-3 activity, and DNA fragmentation in ovarian cancer cells (A2780).</P><P><B>Results</B></P><P>AgNPs with an average size of 20 nm were uniformly dispersed on graphene sheets. The data obtained from the biochemical assays indicate that the rGO–Ag nanocomposite significantly inhibited cell viability in A2780 ovarian cancer cells and increased lactate dehydrogenase leakage, reactive oxygen species generation, caspase-3 activity, and DNA fragmentation compared with other tested nanomaterials such as graphene oxide, rGO, and AgNPs.</P><P><B>Conclusion</B></P><P><I>T. amurensis</I> plant extract-mediated rGO–Ag nanocomposites could facilitate the large-scale production of graphene-based nanocomposites; rGO–Ag showed a significant inhibiting effect on cell viability compared to graphene oxide, rGO, and silver nanoparticles. The nanocomposites could be effective non-toxic therapeutic agents for the treatment of both cancer and cancer stem cells.</P>

Green synthesis of anisotropic silver nanoparticles and its potential cytotoxicity in human breast cancer cells (MCF-7)

Gurunathan, S.,Han, J.W.,Dayem, A.A.,Eppakayala, V.,Park, J.H.,Cho, S.G.,Lee, K.J.,Kim, J.H. Korean Society of Industrial and Engineering Chemi 2013 Journal of industrial and engineering chemistry Vol.19 No.5

We described a green, cost effective and rapid method for synthesizing anisotropic AgNPs using a novel bacterium called Escherichia fergusoni. Furthermore, synthesized AgNPs were characterized by various analytical techniques. The present study demonstrates the efficiency of biologically synthesized AgNPs as a cytotoxic agent against MCF-7 cells and also this study investigates possible molecular mechanisms underlying the cytotoxic effects of AgNPs. AgNPs showed dose dependent cytotoxicity against MCF-7 cells through activation of the lactate dehydrogenase (LDH), reactive oxygen species (ROS) generation and eventually leading to induction of apoptosis which was further confirmed through resulting nuclear fragmentation.

Cytotoxicity and Transcriptomic Analysis of Silver Nanoparticles in Mouse Embryonic Fibroblast Cells

Gurunathan, Sangiliyandi,Qasim, Muhammad,Park, Chanhyeok,Yoo, Hyunjin,Choi, Dong Yoon,Song, Hyuk,Park, Chankyu,Kim, Jin-Hoi,Hong, Kwonho MDPI 2018 INTERNATIONAL JOURNAL OF MOLECULAR SCIENCES Vol.19 No.11

<P>The rapid development of nanotechnology has led to the use of silver nanoparticles (AgNPs) in biomedical applications, including antibacterial, antiviral, anti-inflammatory, and anticancer therapies. The molecular mechanism of AgNPs-induced cytotoxicity has not been studied thoroughly using a combination of cellular assays and RNA sequencing (RNA-Seq) analysis. In this study, we prepared AgNPs using myricetin, an anti-oxidant polyphenol, and studied their effects on NIH3T3 mouse embryonic fibroblasts as an in vitro model system to explore the potential biomedical applications of AgNPs. AgNPs induced loss of cell viability and cell proliferation in a dose-dependent manner, as evident by increased leakage of lactate dehydrogenase (LDH) from cells. Reactive oxygen species (ROS) were a potential source of cytotoxicity. AgNPs also incrementally increased oxidative stress and the level of malondialdehyde, depleted glutathione and superoxide dismutase, reduced mitochondrial membrane potential and adenosine triphosphate (ATP), and caused DNA damage by increasing the level of 8-hydroxy-2′-deoxyguanosine and the expressions of the <I>p53</I> and <I>p21</I> genes in NIH3T3 cells. Thus, activation of oxidative stress may be crucial for NIH3T3 cytotoxicity. Interestingly, gene ontology (GO) term analysis revealed alterations in epigenetics-related biological processes including nucleosome assembly and DNA methylation due to AgNPs exposure. This study is the first demonstration that AgNPs can alter bulk histone gene expression. Therefore, our genome-scale study suggests that the apoptosis observed in NIH3T3 cells treated with AgNPs is mediated by the repression of genes required for cell survival and the aberrant enhancement of nucleosome assembly components to induce apoptosis.</P>

A green chemistry approach for synthesizing biocompatible gold nanoparticles

Gurunathan, Sangiliyandi,Han, JaeWoong,Park, Jung Hyun,Kim, Jin-Hoi Springer 2014 NANOSCALE RESEARCH LETTERS Vol.9 No.1

<P>Gold nanoparticles (AuNPs) are a fascinating class of nanomaterial that can be used for a wide range of biomedical applications, including bio-imaging, lateral flow assays, environmental detection and purification, data storage, drug delivery, biomarkers, catalysis, chemical sensors, and DNA detection. Biological synthesis of nanoparticles appears to be simple, cost-effective, non-toxic, and easy to use for controlling size, shape, and stability, which is unlike the chemically synthesized nanoparticles. The aim of this study was to synthesize homogeneous AuNPs using pharmaceutically important <I>Ganoderma</I> spp<I>.</I> We developed a simple, non-toxic, and green method for water-soluble AuNP synthesis by treating gold (III) chloride trihydrate (HAuCl<SUB>4</SUB>) with a hot aqueous extract of the <I>Ganoderma</I> spp<I>.</I> mycelia. The formation of biologically synthesized AuNPs (bio-AuNPs) was characterized by ultraviolet (UV)-visible absorption spectroscopy, X-ray diffraction (XRD), Fourier transform infrared spectroscopy (FTIR), energy dispersive X-ray (EDX), dynamic light scattering (DLS), and transmission electron microscopy (TEM). Furthermore, the biocompatibility of as-prepared AuNPs was evaluated using a series of assays, such as cell viability, lactate dehydrogenase leakage, and reactive oxygen species generation (ROS) in human breast cancer cells (MDA-MB-231). The color change of the solution from yellow to reddish pink and strong surface plasmon resonance were observed at 520 nm using UV-visible spectroscopy, and that indicated the formation of AuNPs. DLS analysis revealed the size distribution of AuNPs in liquid solution, and the average size of AuNPs was 20 nm. The size and morphology of AuNPs were investigated using TEM. The biocompatibility effect of as-prepared AuNPs was investigated in MDA-MB-231 breast cancer cells by using various concentrations of AuNPs (10 to 100 μM) for 24 h. Our findings suggest that AuNPs are non-cytotoxic and biocompatible. To the best of our knowledge, this is the first report to describe the synthesis of monodispersed, biocompatible, and soluble AuNPs with an average size of 20 nm using <I>Ganoderma</I> spp. This study opens up new possibilities of using an inexpensive and non-toxic mushroom extract as a reducing and stabilizing agent for the synthesis of size-controlled, large-scale, biocompatible, and monodispersed AuNPs, which may have future diagnostic and therapeutic applications.</P>

Enhanced antibacterial and anti-biofilm activities of silver nanoparticles against Gram-negative and Gram-positive bacteria

Gurunathan, Sangiliyandi,Han, Jae Woong,Kwon, Deug-Nam,Kim, Jin-Hoi Springer 2014 NANOSCALE RESEARCH LETTERS Vol.9 No.1

<P>Silver nanoparticles (AgNPs) have been used as antibacterial, antifungal, antiviral, anti-inflammtory, and antiangiogenic due to its unique properties such as physical, chemical, and biological properties. The present study was aimed to investigate antibacterial and anti-biofilm activities of silver nanoparticles alone and in combination with conventional antibiotics against various human pathogenic bacteria. Here, we show that a simple, reliable, cost effective and green method for the synthesis of AgNPs by treating silver ions with leaf extract of <I>Allophylus cobbe.</I> The <I>A. cobbe</I>-mediated synthesis of AgNPs (AgNPs) was characterized by ultraviolet-visible absorption spectroscopy, X-ray diffraction (XRD), Fourier transform infrared spectroscopy (FTIR), X-ray photoelectron spectroscopy (XPS), dynamic light scattering (DLS), and transmission electron microscopy (TEM). Furthermore, the antibacterial and anti-biofilm activity of antibiotics or AgNPs, or combinations of AgNPs with an antibiotic was evaluated using a series of assays: such as <I>in vitro</I> killing assay, disc diffusion assay, biofilm inhibition, and reactive oxygen species generation in <I>Pseudomonas aeruginosa, Shigella flexneri, Staphylococcus aureus</I>, and <I>Streptococcus pneumonia.</I> The results suggest that, in combination with antibiotics, there were significant antimicrobial and anti-biofilm effects at lowest concentration of AgNPs using a novel plant extract of <I>A. cobbe</I>, otherwise sublethal concentrations of the antibiotics. The significant enhancing effects were observed for ampicillin and vancomycin against Gram-negative and Gram-positive bacteria, respectively. These data suggest that combining antibiotics and biogenic AgNPs can be used therapeutically for the treatment of infectious diseases caused by bacteria. This study presented evidence of antibacterial and anti-biofilm effects of <I>A. cobbe</I>-mediated synthesis of AgNPs and their enhanced capacity against various human pathogenic bacteria. These results suggest that AgNPs could be used as an adjuvant for the treatment of infectious diseases.</P>

Antibacterial Efficacy of Silver Nanoparticles on Endometritis Caused by <i>Prevotella melaninogenica</i> and <i>Arcanobacterum pyogenes</i> in Dairy Cattle

Gurunathan, Sangiliyandi,Choi, Yun-Jung,Kim, Jin-Hoi MDPI 2018 INTERNATIONAL JOURNAL OF MOLECULAR SCIENCES Vol.19 No.4

<P>Bovine postpartum diseases remain one of the most significant and highly prevalent illnesses with negative effects on the productivity, survival, and welfare of dairy cows. Antibiotics are generally considered beneficial in the treatment of endometritis; however, frequent usage of each antibiotic drug is reason for the emergence of multidrug resistance (MDR) of the pathogenic microorganisms, representing a major impediment for the successful diagnosis and management of infectious diseases in both humans and animals. We synthesized silver nanoparticles (AgNPs) with an average size of 10 nm using the novel biomolecule apigenin as a reducing and stabilizing agent, and evaluated the efficacy of the AgNPs on the MDR pathogenic bacteria <I>Prevotella melaninogenica</I> and <I>Arcanobacterium pyogenes</I> isolated from uterine secretion samples. AgNPs inhibited cell viability and biofilm formation in a dose- and time-dependent manner. Moreover, the metabolic toxicity of the AgNPs was assessed through various cellular assays. The major toxic effect of cell death was caused by an increase in oxidative stress, as evidenced by the increased generation of reactive oxygen species (ROS), malondialdehyde, protein carbonyl content, and nitric oxide. The formation of ROS is considered to be the primary mechanism of bacterial death. Therefore, the biomolecule-mediated synthesis of AgNPs shows potential as an alternative antimicrobial therapy for bovine metritis and endometritis.</P>

Synthesis of aminosilane crosslinked cationomeric waterborne polyurethane nanocomposites and its physicochemical properties

Gurunathan, T.,Chung, Jin Suk Elsevier 2017 Colloids and surfaces. A, Physicochemical and engi Vol.522 No.-

<P><B>Abstract</B></P> <P>A series of cottonseed oil based waterborne polyurethane–silica (CSOWPU–Si) hybrid materials were prepared via the chemically interaction between NCO groups of polyurethane prepolymer and the surface of 3-aminopropyl trimethoxysilane (APTMS). The biobased triglyceride oils were first epoxidized cottonseed oil followed by oxirane ring-opened with varying polyhydroxy (OH) fatty acid numbers. The attached modified APTMS thus performed the dual roles not only chain extender filler but including reinforcing agent in the resulting hybrid coatings. Fourier transform infrared spectra expose the crosslinking interaction between polyurethane and the appearance of silica nanoparticles in the polymer matrix. The <SUP>29</SUP>Si solid-state NMR spectra sign the formation and the behavior of siloxane linkage in the CSOWPU–Si nanocomposites films. Dynamic mechanical analysis (DMA) studies show that the appearance of silica nanoparticles provides rigidity to CSOWPU–Si film, thereby enhancing the storage modulus. The effect of crosslinking density and thermophysical and mechanical properties of the polyurethane and the resulting hybrid materials films was evaluated by the differential scanning calorimetry (DSC), thermal gravimetric analysis (TGA), and measurement of the mechanical properties. This work renders a new effective and promising route of utilizing biorenewable for the development of CSOWPU–Si hybrid materials with high performance coating applications.</P> <P><B>Highlights</B></P> <P> <UL> <LI> New biobased CSOWPU–Si waterborne nanocomposites were synthesized. </LI> <LI> Silica nanoparticles combined with WPU matrix through covalent cross-linking. </LI> <LI> CSOWPU–Si waterborne nanocomposites were prepared by different APTMS incorporation routes. </LI> <LI> Thermal and mechanical properties of the coating were enhanced with the addition of APTMS. </LI> </UL> </P> <P><B>Graphical abstract</B></P> <P>[DISPLAY OMISSION]</P>

Visible light active pristine and Fe³⁺ doped CuGa₂O₄ spinel photocatalysts for solar hydrogen production

Gurunathan, K.,Baeg, J.-O.,Lee, S.M.,Subramanian, E.,Moon, S.-J.,Kong, K.-j. Pergamon Press ; Elsevier Science Ltd 2008 International journal of hydrogen energy Vol.33 No.11

Spinel metal oxide photocatalysts, a rarely studied group in visible light driven photocatalytic decomposition of H<SUB>2</SUB>S and solar H<SUB>2</SUB> production, have been investigated in the present work. d<SUP>10</SUP> p-block element, Ga containing spinel CuGa<SUB>2</SUB>O<SUB>4</SUB> in pristine and Fe<SUP>3+</SUP>doped (CuGa<SUB>2-x</SUB>Fe<SUB>x</SUB>O<SUB>4</SUB>, x=0.6) states, was prepared by ceramic route without/with noble metal oxide, NiO/RuO<SUB>2</SUB> loading to the extent of 1wt%. XRD analysis reveals a single-phase cubic spinel crystalline structure for all the catalysts. FESEM displays an irregular-shaped grain morphology for CuGa<SUB>2</SUB>O<SUB>4</SUB> and smaller size almost cubic particles for CuGa<SUB>2-x</SUB>Fe<SUB>x</SUB>O<SUB>4</SUB>. Energy dispersive X-ray spectroscopy suggests a chemical composition consistent with the stoichiometric molecular formula. Optically, the catalysts display an intensive light absorption in UV and visible regions with an onset at about 900nm in the near IR region. Fe<SUP>3+</SUP> doping constructively influences the morphology and optical properties of pristine CuGa<SUB>2</SUB>O<SUB>4</SUB>. All these physico-chemical and material characteristics infuse a facile catalytic function into the prepared spinel oxides such that the naked CuGa<SUB>2</SUB>O<SUB>4</SUB> and CuGa<SUB>2-x</SUB>Fe<SUB>x</SUB>O<SUB>4</SUB> spinels exhibit a moderate to fairly good photocatalytic activity while the co-catalyst-loaded CuGa<SUB>2-x</SUB>Fe<SUB>x</SUB>O<SUB>4</SUB> spinel performs an exceedingly good photocatalytic activity with 15% quantum efficiency. Thus, the present work leads to the emergence of functionally high performance, stable and visible active (λ>=420nm) photocatalysts in the spinel group for the production of solar hydrogen from H<SUB>2</SUB>S.