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>

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>

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.

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>

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>

<i>Ginkgo biloba</i> : a natural reducing agent for the synthesis of cytocompatible graphene

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

<P><B>Background</B></P><P>Graphene is a novel two-dimensional planar nanocomposite material consisting of rings of carbon atoms with a hexagonal lattice structure. Graphene exhibits unique physical, chemical, mechanical, electrical, elasticity, and cytocompatible properties that lead to many potential biomedical applications. Nevertheless, the water-insoluble property of graphene restricts its application in various aspects of biomedical fields. Therefore, the objective of this work was to find a novel biological approach for an efficient method to synthesize water-soluble and cytocompatible graphene using <I>Ginkgo biloba</I> extract (GbE) as a reducing and stabilizing agent. In addition, we investigated the biocompatibility effects of graphene in MDA-MB-231 human breast cancer cells.</P><P><B>Materials and methods</B></P><P>Synthesized graphene oxide (GO) and GbE-reduced GO (Gb-rGO) were characterized using various sequences of techniques: ultraviolet-visible (UV-vis) spectroscopy, Fourier-transform infrared spectroscopy (FTIR), dynamic light scattering (DLS), scanning electron microscopy (SEM), atomic force microscopy (AFM), and Raman spectroscopy. Biocompatibility of GO and Gb-rGO was assessed in human breast cancer cells using a series of assays, including cell viability, apoptosis, and alkaline phosphatase (ALP) activity.</P><P><B>Results</B></P><P>The successful synthesis of graphene was confirmed by UV-vis spectroscopy and FTIR. DLS analysis was performed to determine the average size of GO and Gb-rGO. X-ray diffraction studies confirmed the crystalline nature of graphene. SEM was used to investigate the surface morphologies of GO and Gb-rGO. AFM was employed to investigate the morphologies of prepared graphene and the height profile of GO and Gb-rGO. The formation of defects in Gb-rGO was confirmed by Raman spectroscopy. The biocompatibility of the prepared GO and Gb-rGO was investigated using a water-soluble tetrazolium 8 assay on human breast cancer cells. GO exhibited a dose-dependent toxicity, whereas Gb-rGO-treated cells showed significant biocompatibility and increased ALP activity compared to GO.</P><P><B>Conclusion</B></P><P>In this work, a nontoxic natural reducing agent of GbE was used to prepare soluble graphene. The as-prepared Gb-rGO showed significant biocompatibility with human cancer cells. This simple, cost-effective, and green procedure offers an alternative route for large-scale production of rGO, and could be used for various biomedical applications, such as tissue engineering, drug delivery, biosensing, and molecular imaging.</P>

Antibacterial activity of dithiothreitol reduced graphene oxide

Gurunathan, S.,Han, J.W.,Dayem, A.A.,Eppakayala, V.,Park, M.R.,Kwon, D.N.,Kim, J.H. Korean Society of Industrial and Engineering Chemi 2013 Journal of industrial and engineering chemistry Vol.19 No.4

A green and simple approach is described for the large scale synthesis of reduced graphene oxide (rGO). The transition of graphene oxide (GO) into graphene was confirmed using various analytical techniques. Raman spectroscopy data indicate the partial removal of oxygen-containing functional groups from the surface of GO and formation of graphene. X-ray diffraction (XRD) was used to investigate the crystallinity of graphene nanosheets. The antibacterial activity of GO and rGO was evaluated using cell viability, reactive oxygen species (ROS) production and DNA fragmentation assays. The results suggest that GO and rGO possessed an excellent antimicrobial activity against Escherichia coli.

Green synthesis of graphene and its cytotoxic effects in human breast cancer cells

Gurunathan, Sangiliyandi,Han, Jae Woong,Eppakayala, Vasuki,Kim, Jin-Hoi Dove Medical Press 2013 International journal of nanomedicine Vol.8 No.-

<P><B>Background:</B></P><P>This paper describes an environmentally friendly (“green”) approach for the synthesis of soluble graphene using <I>Bacillus marisflavi</I> biomass as a reducing and stabilizing agent under mild conditions in aqueous solution. In addition, the study reported here investigated the cytotoxicity effects of graphene oxide (GO) and bacterially reduced graphene oxide (B-rGO) on the inhibition of cell viability, reactive oxygen species (ROS) generation, and membrane integrity in human breast cancer cells.</P><P><B>Methods:</B></P><P>The reduction of GO was characterized by ultraviolet–visible spectroscopy. Size distribution was analyzed by dynamic light scattering. Further, X-ray diffraction and high-resolution scanning electron microscopy were used to investigate the crystallinity of graphene and the morphologies of prepared graphene, respectively. The formation of defects further supports the bio-functionalization of graphene, as indicated in the Raman spectrum of B-rGO. Surface morphology and the thickness of the GO and B-rGO were analyzed using atomic force microscopy, while the biocompatibility of GO and B-rGO were investigated using WST-8 assays on MCF-7 cells. Finally, cellular toxicity was evaluated by ROS generation and membrane integrity assays.</P><P><B>Results:</B></P><P>In this study, we demonstrated an environmentally friendly, cost-effective, and simple method for the preparation of water-soluble graphene using bacterial biomass. This reduction method avoids the use of toxic reagents such as hydrazine and hydrazine hydrate. The synthesized soluble graphene was confirmed using various analytical techniques. Our results suggest that both GO and B-rGO exhibit toxicity to MCF-7 cells in a dose-dependent manner, with a dose > 60 μg/mL exhibiting obvious cytotoxicity effects, such as decreasing cell viability, increasing ROS generation, and releasing of lactate dehydrogenase.</P><P><B>Conclusion:</B></P><P>We developed a green and a simple approach to produce graphene using bacterial biomass as a reducing and stabilizing agent. The proposed approach confers B-rGO with great potential for various biological and biomedical applications.</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.

Nanoparticle-Mediated Combination Therapy: Two-in-One Approach for Cancer

Gurunathan, Sangiliyandi,Kang, Min-Hee,Qasim, Muhammad,Kim, Jin-Hoi MDPI 2018 INTERNATIONAL JOURNAL OF MOLECULAR SCIENCES Vol.19 No.10

<P>Cancer represents a group of heterogeneous diseases characterized by uncontrolled growth and spread of abnormal cells, ultimately leading to death. Nanomedicine plays a significant role in the development of nanodrugs, nanodevices, drug delivery systems and nanocarriers. Some of the major issues in the treatment of cancer are multidrug resistance (MDR), narrow therapeutic window and undesired side effects of available anticancer drugs and the limitations of anticancer drugs. Several nanosystems being utilized for detection, diagnosis and treatment such as theranostic carriers, liposomes, carbon nanotubes, quantum dots, polymeric micelles, dendrimers and metallic nanoparticles. However, nonbiodegradable nanoparticles causes high tissue accumulation and leads to toxicity. MDR is considered a major impediment to cancer treatment due to metastatic tumors that develop resistance to chemotherapy. MDR contributes to the failure of chemotherapies in various cancers, including breast, ovarian, lung, gastrointestinal and hematological malignancies. Moreover, the therapeutic efficiency of anticancer drugs or nanoparticles (NPs) used alone is less than that of the combination of NPs and anticancer drugs. Combination therapy has long been adopted as the standard first-line treatment of several malignancies to improve the clinical outcome. Combination therapy with anticancer drugs has been shown to generally induce synergistic drug actions and deter the onset of drug resistance. Therefore, this review is designed to report and analyze the recent progress made to address combination therapy using NPs and anticancer drugs. We first provide a comprehensive overview of the angiogenesis and of the different types of NPs currently used in treatments of cancer; those emphasized in this review are liposomes, polymeric NPs, polymeric micelles (PMs), dendrimers, carbon NPs, nanodiamond (ND), fullerenes, carbon nanotubes (CNTs), graphene oxide (GO), GO nanocomposites and metallic NPs used for combination therapy with various anticancer agents. Nanotechnology has provided the convenient tools for combination therapy. However, for clinical translation, we need continued improvements in the field of nanotechnology.</P>