G. Sathishkumar

Biogenic silver nanoparticles for cancer treatment: An experimental report

A generation of nanoparticles research has discussed recently. It is mandatory to elaborate the applications of biogenic nanoparticles in general and anticancereous property in particular. The present study was aimed to investigate the in vitro cytotoxicity effect of biogenic silver nanoparticles (AgNPs) against human breast cancer (MCF-7) cells towards the development of anticancer agent. Biogenic AgNPs were achieved by employing Sesbania grandiflora leaf extract as a novel reducing agent. It was well characterized by FESEM, EDAX and spectral studies showed spherical shaped nanoparticles in the size of 22 nm in slightly agglomerated form. It was surprising that biogenic AgNPs showed cytotoxic effect against MCF-7 cell lines were confirmed by MTT, AO-EB, Hochest and COMET assays. There was an immediate induction of cellular damage in terms of loss of cell membrane integrity, oxidative stress and apoptosis were found in the cell which treated with AgNPs. This may be a first report on anti-MCF-7 property of biogenic AgNPs in the fourth generation of nanoparticles research. It is necessary to study the formulation and clinical trials to establish the nano drug to treat cancer cells.

An investigation on the cytotoxicity and caspase-mediated apoptotic effect of biologically synthesized silver nanoparticles using Podophyllum hexandrum on human cervical carcinoma cells

Now-a-days synthesis and characterization of silver nanoparticles (AgNPs) through biological entity is quite interesting to employ AgNPs for various biomedical applications in general and treatment of cancer in particular. This paper presents the green synthesis of AgNPs using leaf extract of Podophyllum hexandrum Royle and optimized with various parameters such as pH, temperature, reaction time, volume of extract and metal ion concentration for synthesis of AgNPs. TEM, XRD and FTIR were adopted for characterization. The synthesized nanoparticles were found to be spherical shaped with average size of 14 nm. Effects of AgNPs were analyzed against human cervical carcinoma cells by MTT Assay, quantification of ROS, RT-PCR and western blotting techniques. The overall result indicates that AgNPs can selectively inhibit the cellular mechanism of HeLa by DNA damage and caspase mediated cell death. This biological procedure for synthesis of AgNPs and selective inhibition of cancerous cells gives an alternative avenue to treat human cancer effectively.

Phyto-synthesis of silver nanoscale particles using Morinda citrifolia L. and its inhibitory activity against human pathogens.

Leaf extract of Morinda citrifolia L. was assessed for the synthesis of silver nanoscale particles under different temperature and reaction time. Synthesized nanoscale (MCAgNPs) particles were confirmed by analysing the excitation of surface plasmon resonance (SPR) using UV-visible spectrophotometer at 420 nm. Further SEM, HRTEM analysis confirmed the range of particle size between 10 and 60 nm and SEAD pattern authorizes the face centered cubic (fcc) crystalline nature of the MCAgNPs. Fourier transform infrared spectrum (FTIR) of synthesized MCAgNPs confirms the presence of high amount of phenolic compounds in the plant extract which may possibly influence the reduction process and stabilization of nanoparticles. Further, inhibitory activity of MCAgNPs and plant extract were tested against human pathogens like Eschericia coli, Pseudomonas aeroginosa, Klebsiella pneumoniae, Enterobacter aerogenes, Bacillus cereus and Enterococci sp. The results indicated that the MCAgNPs showed moderate inhibitory actions against human pathogens than crude plant extract, demonstrating its antimicrobial value against pathogenic diseases.

Antibacterial and cytotoxic potential of silver nanoparticles synthesized using latex of Calotropis gigantea L.

The present study aimed to synthesis silver nanoparticles (AgNPs) in a greener route using aqueous latex extract of Calotropis gigantea L. toward biomedical applications. Initially, synthesis of AgNPs was confirmed through UV-Vis spectroscopy which shows the surface plasmonic resonance peak (SPR) at 420 nm. Fourier transform infrared spectroscopy (FTIR) analysis provides clear evidence that protein fractions present in the latex extract act as reducing and stabilizing bio agents. Energy dispersive X-ray (EDAX) spectroscopy confirms the presence of silver as a major constituent element. X-ray diffractograms displays that the synthesized AgNPs were biphasic crystalline nature. Electron microscopic studies such as Field emission scanning electron microscopic (Fe-SEM) and Transmission electron microscope (TEM) reveals that synthesized AgNPs are spherical in shape with the size range between 5 and 30 nm. Further, crude latex aqueous extract and synthesized AgNPs were evaluated against different bacterial pathogens such as Bacillus cereus, Enterococci sp, Shigella sp, Pseudomonas aeruginosa, Klebsiella pneumonia, Staphylococcus aureus and Escherichia coli. Compared to the crude latex aqueous extract, biosynthesized AgNPs exhibits a remarkable antimicrobial activity. Likewise in vitro anticancer study manifests the cytotoxicity value of synthesized AgNPs against tested HeLa cells. The output of this study clearly suggesting that biosynthesized AgNPs using latex of C. gigantea can be used as promising nanomaterial for therapeutic application in context with nanodrug formulation.

Dendrophthoe falcata (L.f) Ettingsh (Neem mistletoe): A potent bioresource to fabricate silver nanoparticles for anticancer effect against human breast cancer cells (MCF-7)

Fabrication of metal nano scale particles through environmentally acceptable greener route has been focused with much interest in the present scenario. In this study aqueous leaf extract of mistletoe Dendrophthoe falcata (L.f) Ettingsh was successfully employed as a reducing and stabilizing agent to fabricate nanosilver particles (AgNPs) for biomedical applications. Various reactions conditions such as temperature, pH, concentration of metal ion, incubation time and stoichiometric proportion of the reaction mixture were optimized to attain narrow size range particles with maximum synthesis rate. Fabricated crystalline AgNPs with spherical structure (5-45 nm) were characterized with UV-Visible spectroscopy, Field emission scanning electron microscope (FESEM), High resolution transmission electron microscope (HRTEM) and Selected area diffraction pattern (SEAD). Further the fabricated AgNPs were studied for their stability and surface chemistry through Fourier transform infrared spectroscopy (FTIR), Energy dispersive X-ray spectroscopy (EDAX) and inductively coupled plasma optical emission spectroscopy (ICP-OES). Moreover, fabricated AgNPs and aqueous leaf extract were assessed for their cytotoxicity effect against human breast carcinoma cell line (MCF-7). It is concluded that colloidal AgNPs can be developed as an imminent candidature for cancer therapy.

Optimization of reaction conditions to fabricate nano-silver using Couroupita guianensis Aubl. (leaf & fruit) and its enhanced larvicidal effect.

Currently bioactive principles of plants and their nanoproducts have been extensively studied in agriculture and medicine. In this study Couroupita guianensis Aubl. leaf and fruit extracts were selected for rapid and cost-effective synthesis of silver nanoparticles (leaf-LAgNPs and fruit-FAgNPs). Various physiological conditions such as temperature, pH, concentration of metal ions, stoichiometric proportion of reaction mixture and reaction time showed influence on the size, dispersity and synthesis rate of AgNPs. Generation of AgNPs was initially confirmed with the surface plasmon vibrations at 420 nm in UV-visible spectrophotometer. The results recorded from X-ray diffractometer (XRD) and Transmission electron microscope (TEM) supports the biosynthesis of cubic crystalline LAgNPs & FAgNPs with the size ranges between 10-45 nm and 5-15 nm respectively. Surface chemistry of synthesized AgNPs was studied with Fourier transform infrared spectroscopy (FTIR), it reveals that water soluble phenolic compounds present in the extracts act as reducing and stabilizing agent. Leaf, fruit extracts and synthesized AgNPs were evaluated against IV instar larvae of Aedes aegypti (Diptera; Culicidae). Furthermore, different extracts and synthesized AgNPs showed dose dependent larvicidal effect against A. aegypti after 24h of treatment. Compare to all extracts such as ethyl acetate (leaf; LC50 - 44.55 ppm and LC90 - 318.39 ppm & fruit; LC50 - 49.96 ppm and LC90 - 568.84 ppm respectively) and Methanol (leaf; LC50 - 85.75 ppm and LC90 - 598.63 ppm & fruit; LC50 - 67.78 ppm and LC90 - 714.45 ppm respectively) synthesized AgNPs showed extensive mortality rate (LAgNPs; LC50 - 2.1 ppm and LC90 - 5.59 ppm & FAgNPs; LC50 - 2.09 ppm and LC90 - 5.7 ppm). Hence, this study proves that C. guianensis is a potential bioresource for stable, reproducible nanoparticle synthesis (AgNPs) and also can be used as an efficient mosquito control agent.

Fabrication of nano-silver particles using Cymodocea serrulata and its cytotoxicity effect against human lung cancer A549 cells line

The present study reports, green synthesis of bioactive silver nanoparticles (AgNPs) under different temperature (60°C, room temperature and 4° refrigerator) using the aqueous extract of sea grass Cymodocea serrulata as a potential bioreductant. Increased temperature fabricates more AgNPs compare to room temperature and refrigerator condition. At first the reduction of Ag(+) ions were confirmed through color change which produces an absorbance spectra at 420nm in UV-Visible spectrophotometer. Additionally various exclusive instrumentations such as X-ray diffraction (XRD), Dynamic light scattering (DLS), scanning electron microscope (SEM) analysis and Transmission electron microscope (TEM) were authorizes the biosynthesis and physio-chemical characterization of AgNPs. From Fourier transform infrared spectroscopy (FTIR) analysis, it was identified that the water soluble fractions of the sea grass mainly responsible for reduction of ionic silver (Ag(+)) into (Ag(0)) nano-ranged particles and also they act as stabilizing agent to sustain the durability of NPs for long period of time. Further, synthesized AgNPs shows potential cytotoxicity against human lung cancer A549 cells (LD50-100μg/ml). The overall results suggest that C. serrulata is a valuable bioresource to generate rapid and eco-friendly bioactive AgNPs towards cancer therapy.

Biogenic metal nanoformulations induce Bax/Bcl2 and caspase mediated mitochondrial dysfunction in human breast cancer cells (MCF 7)

Nanostructures of noble metals have been extensively studied recently because of their impressive physiochemical properties and wide range of applications in biology and medicine. In this study, the anticancer efficacy of green synthesized silver and gold nanoparticles (AgNPs and AuNPs) was assessed against human breast carcinoma cells (MCF-7). Treatment with different concentrations of NPs triggers the cellular toxicity in a dose and time dependent manner. Morphological features of apoptosis were measured using cell wall integrity, acridine orange/ethidium bromide and Hochest staining methods which clearly distinguishes the viable cells and the cells undergoing apoptosis. Flow cytometry and DNA fragmentation analysis were also used to substantiate that NPs induced cytotoxicity was primarily mediated by G2/M cell cycle arrest and apoptosis. NPs provoke intracellular reactive oxygen species that cause damage to various cellular components. Furthermore, the gene expression studies such as reverse transcription – polymerase chain reaction, quantitative polymerase chain reaction and western blot analysis shows the upregulation of Bax, Bcl2, caspases-6 and -9, PARP, p53 and downregulation of Bcl-2 depicts the induction of apoptosis upon exposure to NPs. The overall results clearly shows that green synthesized metal NPs can potentially inhibit the proliferation of MCF-7 cells and trigger apoptosis through Bax/Bcl2 and caspase–cascade mediated mitochondrial dysfunction. This research concludes that biogenic metal nano-drug formulations can be utilized for cancer chemotherapy.

Correction: Dietary flavone chrysin (5,7-dihydroxyflavone ChR) functionalized highly-stable metal nanoformulations for improved anticancer applications

Nanomaterials of noble metals with unique size, shape and composition receives much attention owing to their versatile functionality in personalized cancer nanomedicine. Chrysin (ChR), a natural anticancer bioflavonoid, emerged as a potential drug therapy for almost all types of cancer, however it has poor solubility and bioavailability. Herein, we report a new approach to formulate biofunctionalized metallic silver (ChR–AgNPs) and gold (ChR–AuNPs) nanoparticles using ChR as a direct bioreductant and capping agent. Size and dispersity of nanoparticles (NPs) were controlled through fixing different reaction conditions such as the temperature, pH, concentration of metal ion, stoichiometric proportion of the reaction mixture and incubation time based on their optical properties and SPR effect in UV-visible spectroscopy. The role of hydroxyl and carbonyl groups in functionalizing the metal ions with ChR was confirmed with Fourier transform infrared spectroscopy (FTIR) and X-ray photoelectron spectroscopy (XPS) analysis. It was also substantiated that the oxygen group from ChR donates electrons to metal ion and results in complexation; ionic Ag+ and Au3+ were reduced to Ag0 and Au0 nano-forms. The physiochemical state of obtained NPs was characterized through different exclusive instrumentation, which shows the presence of highly-stable, spherical, crystalline ChR–AgNPs and ChR–AuNPs with an average size of 14 ± 6 nm and 6 ± 2 nm respectively. In vitro anticancer results revealed that the formulated metallic NPs exhibit enhanced cytotoxicity over ChR in the treatment of two different breast carcinoma cell lines (MDA-MB-231 and MDA-MB-468). Furthermore, it was evident that the NPs cause cell death via the induction of apoptosis. A hemolysis assay with human erythrocytes demonstrates good blood biocompatibility of the NPs. Thus, the ChR functionalized metal NPs can be potentially employed as a combinational drug-nano platform for breast cancer therapy.

Formulation of iron oxide nanoparticles using exopolysaccharide: evaluation of their antibacterial and anticancer activities

In the present study, we report the formulation, characterization, and in vitro antibacterial and cytotoxicity effects of exopolysaccharide (EPS) stabilized iron oxide nanoparticles (FeONPs) against the human epidermoid carcinoma cell line (A431). EPS is extracted from a spore-forming strain of Bacillus subtilis, VT03, isolated from the gut microbiome of the freshwater fish Oreochromis mossambicus (Tilapia). FTIR, 1H NMR and 13C NMR spectroscopic studies show the presence of sugar moieties, confirming that EPS might be a glucan. Later, EPS is used as an eco-friendly reducing and stabilizing agent for the formulation of iron oxide nanoparticles (FeONPs). Initially, the generation of nanoscale FeO was confirmed through the formation of a black-coloured precipitate with an absorbance maxima at 250–300 nm in a UV-visible spectrometer. X-ray diffraction (XRD) planes clearly confirm that the synthesized FeONPs are in the cubic spinel phase. The morphometric features of the synthesized FeONPs are exclusively studied using electron microscopy (FESEM and HRTEM) which shows spherical FeONPs in sizes ranging between 75–120 nm; the mean size was found to be 106 ± 12 nm. Additionally, energy dispersive X-ray analysis (EDAX), selected area emission diffraction (SAED) and dynamic light scattering (DLS) confirms the purity and homogeneity of the synthesized FeONPs. The vibrating sample magnetometer (VSM) technique reveals the presence of both ferro- and antiferromagnetic phases in the EPS-stabilized FeONPs. Further, the inhibitory activity of EPS-stabilized FeONPs against human and fish pathogenic strains such as Aeromonas hydrophila (ATCC 49140), Aeromonas hydrophila (MTCC 1739), Aeromonas sobria (MTCC 3613) and Aeromonas hydrophila (obtained from OIE Reference Laboratory, C. Abdul Hakeem College, Melvisharam) was assessed. The in vitro cytotoxicity effects of free EPS and EPS-stabilized FeONPs were probed in the human epidermoid carcinoma cell line A431. The IC50 values of EPS and EPS-stabilized FeONPs were found to be 350.18 and 62.946 μg ml−1 respectively. Further, acridine orange/ethidium bromide (AO/EtBr) staining of A431 cells at different time intervals clearly distinguishes the live cells and the cells that have undergone apoptotic cell death. In conclusion, our research paves the way for a facile and greener route to synthesize FeONPs at room temperature. On the other hand, this study also proves that the formulated multifunctional hybrid FeONPs have remarkable qualities such as enhanced bioavailability and magnetic properties. This can be developed into a successful theragnostic platform for cancer treatment.