Applied Nanoscience (v.6, #5)

pACC1 peptide loaded chitosan nanoparticles induces apoptosis via reduced fatty acid synthesis in MDA-MB-231 cells by Jagatheesh Kaliaperumal; Natarajan Hari; Padarthi Pavankumar; Namasivayam Elangovan (615-627).
The development of formulations with therapeutic peptides has been restricted to poor cell penetration and in this attempt; we developed pACC1 peptide loaded chitosan nanoparticles. The prepared nanoparticles were characterized with FT-IR, XRD, SEM and TEM. In addition, the suitable formulation was evaluated for hemocompatibility, plasma stability and embryo toxicity using Danio rerio embryo model. The results showed that pACC1 peptide loaded chitosan nanoparticles were compatible with plasma. They possess sustained release pattern and also found to be safe up to 300 mg/L in embryo toxicity tests. Cytotoxicity assays with MDA-MB-231 cell lines suggested that, pACC1 peptide loaded chitosan nanoparticles were capable of enhanced cellular penetration and reduced palmitic acid content, which was confirmed by H1 NMR. Hence, these nanoparticles could be employed as excellent adjuvant therapeutics while treating solid tumors with multi-drug resistance.
Keywords: Peptide pACC1; Chitosan; Nanoparticles; Danio rerio ; Cytotoxicity; NMR H1

In the present work, pure and Sr2+ ions substituted Mg ferrite nanoparticles (NPs) had been prepared by co-precipitation method and their structural, optical, and magnetic properties at different calcination temperatures were studied. On this purpose, thermo gravimetric and differential thermal analysis (TG–DTA), Fourier transform infrared spectroscopy (FT-IR), X-ray diffraction (XRD), scanning electron microscopy, UV–Visible diffused reflectance spectroscopy, impedance spectroscopy, and vibrating sample magnetometer were carried out. The exo- and endothermic processes of synthesized precursors were investigated by TG–DTA measurements. The structural properties of the obtained products were examined by XRD analysis and show that the synthesized NPs are in the cubic spinel structure. The existence of two bands around 578–583 and 430–436 cm−1 in FT-IR spectrum also confirmed the formation of spinel-structured ferrite NPs. The lattice constants and particle size are estimated using XRD data and found to be strongly dependent on calcination temperatures. The optical, electrical, and magnetic properties of ferrite compositions also investigated and found to be strongly dependant on calcination temperatures.
Keywords: Magnetic ferrites; Impedance spectroscopy; VSM

The flow of mixed convection nanofluid over wedge under the effects of porous medium is investigated. The HFE-7100 Engineered Fluid having Nimonic 80a metal nanoparticles of spherical and non-spherical shapes with different sizes is used. The particle shape effects on Bejan number and entropy generation are taken into account. The system of partial differential equations is first written in terms of ordinary differential equations using adequate similarity transformations and then solved analytically. Analytical solutions of the resulting equations are obtained for the velocity and temperature profiles. Simultaneous effects of porous medium, particle volume friction, mixed convection parameter, and angle of wedge in the presence of different shapes nanoparticles are demonstrated graphically. Effects of particle concentrations, sizes on wall stress, heat transfer coefficient of Skin friction, and Nusselt are discussed in the form of tables.
Keywords: Nonlinear partial differential equations; Mixed convection; Entropy generation; Shape effects; Nanofluid and porous medium

Green hydrothermal synthesis and optical properties of γ-Gd2S3 nanoparticles by Sonika Khajuria; Jigmet Ladol; Sumit Sanotra; Haq Nawaz Sheikh (653-658).
Green synthesis of γ-Gd2S3 nanoparticles was carried out using low-temperature hydrothermal route in autoclave. A 1:1 mixture of ionic liquid 1-ethyl-3-methylimidazolium ethyl sulfate, ([EMIM][EtSO4]), and water was used as a solvent. Synthesized nanoparticles were characterized by x-ray powder diffraction (XRPD), scanning electron microscopy (SEM), UV–visible spectroscopy (UV–vis), particle size by dynamic light scattering (DLS) technique, and photoluminescence (PL) studies. XRPD suggests cubic Th3P4-type structure for obtained Gd2S3 nanoparticles. The size of synthesized nanoparticles is about 86 nm. Optical band gap for these nanoparticles estimated from electronic spectrum is 2.95 eV which shows blue shift from values reported for bulk Gd2S3 due to pronounced quantum mechanical effect. These nanoparticles show sharp emission peak at 385 nm and a broad shoulder at 475 nm when excited at 260 nm.
Keywords: Rare earth sesquisulfide; γ-Gd2S3 ; Nanoparticles; Hydrothermal synthesis; Optical band gap; Photoluminescence

The aim of the present work was to synthesize highly homogeneous synthetic recognition units for the selective and specific separation of S-ibuprofen from its closely related structural analogues using molecular imprinting technology. The molecular imprinted polymer wrapped on functionalized multiwalled carbon nanotubes (MWCNT-MIP) was synthesized using S-ibuprofen as the template in the imprinting process. The characterization of the products and intermediates were done by FT-IR spectroscopy, PXRD, TGA, SEM and TEM techniques. The high regression coefficient value for Langmuir adsorption isotherm (R 2 = 0.999) showed the homogeneous imprint sites and surface adsorption nature of the prepared polymer sorbent. The nano-MIP followed a second-order kinetics (R 2  = 0.999) with a rapid adsorption rate which also suggested the formation of recognition sites on the surface of MWCNT-MIP. MWCNT-MIP showed 83.6 % higher rebinding capacity than its non-imprinted counterpart. The higher relative selectivity coefficient (k′) of the imprinted sorbent towards S-ibuprofen than that for its structural analogues evidenced the capability of the nano-MIP to selectively and specifically rebind the template rather than its analogues.
Keywords: Molecular imprinting; Nanocomposites; Adsorption; S-Ibuprofen; Morphology

CIGS nanostructure: preparation and study using liquid phase method by P. Jakhmola; P. K. Jha; S. P. Bhatnagar (673-679).
Present study is motivated by interesting attainment obtained for copper indium gallium diselenide compound as a light absorbing material for thin-film solar cell. Formation of copper indium gallium diselenide nanostructures via solvothermal method using starting precursors of copper, indium, gallium salts, and selenium powder is represented. Preparation is done by varying x (0.1 and 0.3) in CuIn1−x Ga x Se2 compound at a constant temperature and using ethanolamine as a solvent. Characterization of nanostructures is done using powder X-ray diffraction, scanning electron microscopy, dynamic light scattering, Fourier transform infrared spectroscopy, and UV–Vis spectroscopy. It is found that grown chalcopyrite structure at different x, possess agglomeration in nanostructures. Results indicate that presence of 10 % gallium in copper indium gallium diselenide compound leads to the single-phase growth, prepare at the temperature of 190 °C for 19 h.
Keywords: Copper indium gallium diselenide; Characterization; Nanostructures

An economically viable and “green” process has been developed for the synthesis of silver nanoparticles (AgNPs) with an average size of 7 nm using non-toxic and renewable salmalia malabarica gum (SMG) as reducing and capping agent without using any chemical reducing agent. The effect of various parameters such as concentration of SMG and silver nitrate and reaction time for the synthesis of AgNPs was studied. The synthesized AgNPs are systematically characterized by UV/Vis spectroscopy, Fourier transform infrared spectroscopy, X-ray diffraction and Transmission electron microscopy. The resultant SMG-capped AgNPs are highly stable and had significant antibacterial action on both Escherichia coli (E. coli) and Staphylococcus aureus (S. aureus). The catalytic action of the SMG-capped AgNPs to initiate the reduction of 4-nitrophenol (4-NP) in the presence of NaBH4 has also been reported. The kinetics of the reaction was found to be of pseudo-first-order with respect to the 4-NP.
Keywords: Salmalia malabarica gum (SMG); Silver nanoparticles (AgNPs); Microbial activity; Catalysis; Pseudo-first-order reaction

TiInCrO6-nanomaterial synthesis, characterization and multi applications by J. Kamalakkannan; V. L. Chandraboss; B. Loganathan; S. Prabha; B. Karthikeyan; S. Senthilvelan (691-702).
In this article, we reported the highly reusable undoped titanium dioxide and doped TiInCrO6 nanomaterial by simple precipitation method and sonication technique. The prepared nanomaterials were characterized by X-ray diffraction, field-emission scanning electron microscopy with elementary dispersive X-ray, high-resolution transmission electron microscopy, techniques and ultraviolet and visible-diffuse reflectance studies. The influence of operational parameters such as the effect of catalyst loading dye concentration and chemical oxygen demand measurements had also been investigated. The synthesized TiInCrO6 nanomaterial was proposed as the promising photocatalyst for the degradation of rhodamine B (Rh B) dye and reusability. The mechanism of the photocatalytic effect of the TiInCrO6 nanomaterial has been discussed. Thus, the use of TiInCrO6 in water purification showed potential. The photodegradation of Rh B dye was well described by pseudo-first-order kinetics and high quantum yield. The photovoltaic characterization had been studied, cyclic voltammogram measurements. The antibacterial activity of the prepared nanomaterials had been investigated against Gram negative Escherichia coli and Gram positive Staphylococcus aureus bacterial strains.
Keywords: Nanomaterial; Electronic microscopic analysis; Photocatalysis; Photovoltaic characterization; Cyclic voltammogram (CV); Antibacterial activity

Biogenic synthesis of zinc oxide nanoparticles using Ruta graveolens (L.) and their antibacterial and antioxidant activities by K. Lingaraju; H. Raja Naika; K. Manjunath; R. B. Basavaraj; H. Nagabhushana; G. Nagaraju; D. Suresh (703-710).
In the present investigation, green synthesis of zinc oxide nanoparticles were successfully synthesized by biological method using aqueous stem extract of Ruta graveolens act as reducing agent. Formation of ZnO nanoparticles were characterized by powder X-ray diffraction (PXRD), UV–visible spectroscopy, scanning electron microscopy (SEM) and transmission electron microscopy (TEM) techniques. Zinc oxide nanoparticles were subjected to biological properties such as antibacterial and antioxidant studies. The PXRD pattern reveals that ZnO sample belongs to hexagonal phase with Wurtzite structure. The UV–vis absorption spectrum shows an absorption band at 355 nm due to ZnO nanoparticles. SEM images show that the particles have spherical like structure with large surface area and the average crystallite sizes were found to be in the range ~28 nm. These observations were confirmed by TEM analysis. The ZnO nanoparticles are found to inhibit the antioxidant activity of 1,1-diphenyl-2-picrylhydrazyl free radicals effectively. ZnO Nps exhibit significant bactericidal activity against Gram −ve bacterial strains such as Klebsiella aerogenes, Pseudomonas aeruginosa, Escherichia coli and Gram +ve Staphylococcus aureus by agar well diffusion method.
Keywords: Antibacterial activity; Antioxidant activity; Green synthesis; ZnO nanoparticles; Room temperature

Silver nanoparticles (Ag-NPs) were synthesized from aqueous silver nitrate through a simple route using the leaf extract of Aristolochia indica L. (LAIL) which acted as a reducing as well as capping agent. X-ray diffraction confirmed that the synthesized silver particles have a face centred cubic structure. EDS predicted the presence of elemental silver. The SEM images showed the synthesis of spherically mono-dispersed particles, with nano dimensions accounted by the TEM images. Infra-red spectrum adopted to the different organic functionalities present at the surface of the particles. TGA indicated an overall 11 % weight loss up to 1000 °C, suggesting desorption of biomolecules from the surface. X-ray photoelectron spectroscopy (XPS) analysis revealed the presence of metallic silver nanoparticles. The prepared material was utilized as catalyst in the oxidation of benzyl alcohol with molecular oxygen as the oxidant in methanol, under ambient conditions of temperature and pressure. Also Ag-NPs showed good to moderate anti-microbial activity employing the Agar disc diffusion method against various strains using Ciprofloxacin and Fluconazole as standard. Free radical scavenging activity of the nanoparticles were observed by modified 1,1-diphynyl-2-picrylhydrazyl, DPPH and 2,2-azinobis(3-ethylbenzothiazoline-6-sulfonic acid), ABTS in vitro assays. The work presented here demonstrates the adaptability of the synthesized Ag-NPs in participating as a disinfectant agent, free radical scavenger and an effective oxidation catalyst. The basic premise of attaining sustainability through the green synthesis of smart multifaceted materials has been consciously addressed.
Keywords: Aristolochia indica L.; Silver nitrate; Silver nanoparticles; Molecular oxygen; Free radical scavenging; Sustainability

In this investigation, pot culture experiment was carried out to estimate the ameliorating effect of triazole compounds, namely Triadimefon (TDM), Tebuconazole (TBZ), and Propiconazole (PCZ) on drought stress, photosynthetic pigments, and biochemical constituents of Zea mays L. (Maize). From 30 days after sowing (DAS), the plants were subjected to 4 days interval drought (DID) stress and drought with TDM at 15 mg l−1, TBZ at 10 mg l−1, and PCZ at 15 mg l−1. Irrigation at 1-day interval was kept as control. Irrigation performed on alternative day. The plant samples were collected on 40, 50, and 60 DAS and separated into root, stem, and leaf for estimating the photosynthetic pigments and biochemical constituents. Drought and drought with triazole compounds treatment increased the biochemical glycine betaine content, whereas the protein and the pigments contents chlorophyll-a, chlorophyll-b, total chlorophyll, carotenoid, and anthocyanin decreased when compared to control. The triazole treatment mitigated the adverse effects of drought stress by increasing the biochemical potentials and paved the way to overcome drought stress in corn plant.
Keywords: Drought; Triazole; Triadimefon; Tebuconazole; Propiconazole; Biochemical; Pigment

In this paper, we investigated the effects of aligned magnetic field, thermal radiation, heat generation/absorption, cross-diffusion, viscous dissipation, heat source and chemical reaction on the flow of a nanofluid past an exponentially stretching sheet in porous medium. The governing partial differential equations are transformed to set of ordinary differential equations using self-similarity transformation, which are then solved numerically using bvp4c Matlab package. Finally the effects of various non-dimensional parameters on velocity, temperature, concentration, skin friction, local Nusselt and Sherwood numbers are thoroughly investigated and presented through graphs and tables. We observed that an increase in the aligned angle strengthens the applied magnetic field and decreases the velocity profiles of the flow. Soret and Dufour numbers are helpful to enhance the heat transfer rate. An increase in the heat source parameter, radiation parameter and Eckert number increases the mass transfer rate. Mixed convection parameter has tendency to enhance the friction factor along with the heat and mass transfer rate.
Keywords: Convection; Nanofluid; Radiation; Magnetohydrodynamic (MHD); Dissipation; Stretching sheet; Heat source

Eco-friendly silver nanoparticles (AgNPs) have various applications in modern biotechnology for better outcomes and benefits to the society. In the present study, we report an eco-friendly synthesis of silver nanoparticles using Saraca indica leaf extract. Characterization of S. indica silver nanoparticles (SAgNPs) was carried out by Fourier transform infrared spectroscopy, scanning electron microscopy, energy dispersive spectrometry, Zeta potential, and transmission electron microscopy. SAgNPs showed antimicrobial activity against Gram-negative and Gram-positive bacteria.
Keywords: Sa raca Indira ; Silver nanoparticles; Zeta potential; Transmission electron micro scopy; Scanning electron microscope; Antibacterial activity

Biogenic synthesis of silver nanoparticles and their antioxidant and antibacterial activity by S. Bhakya; S. Muthukrishnan; M. Sukumaran; M. Muthukumar (755-766).
Nanomedicine utilizes biocompatible nanomaterials for diagnostic and therapeutic purposes. The present study reports the use of Helicteres isora root extract for the synthesis of silver nanoparticles (AgNPs). The synthesized AgNPs were initially noticed through visual color change from yellow to reddish brown and further confirmed by surface plasmonic resonance (SPR) band at 450 nm using UV–visible spectroscopy. Morphology and size of AgNPs were determined by transmission electron microscopy (TEM) analysis. X-ray diffraction (XRD) study revealed crystalline nature of AgNPs. The prolonged stability of AgNPs was due to capping of oxidized polyphenols and carboxyl protein which was established by Fourier transform infrared spectroscopy (FTIR) study. In addition, the synthesized AgNPs were tested for antioxidant and antibacterial activities. It showed good antioxidant activity as compared to butylated hydroxytoluene (BHT) and ascorbic acid as standard antioxidant. It could be concluded that H. isora root extract can be used efficiently in the production of potential antioxidant and antibacterial AgNPs for commercial application.
Keywords: Green synthesis; Silver nanoparticles; Helicteres isora, antioxidant; Antibacterial; TEM & FTIR

Green approach for the synthesis and characterization of ZrSnO4 nanopowder by Taimur Athar; Sandeep Kumar Vishwakarma; Avinash Bardia; Razzaq Alabass; Ahmed Alqarlosy; Aleem Ahmed Khan (767-777).
Well-defined structural framework of ZrSnO4 nanopowder has been synthesized for the fabrications of cost-effective and sensitive devices which give final reproducible result with reliability under ideal conditions. The synthesis was carried out at moderate temperature and then finally dried in the laboratory oven and then followed with calcination at 1000 °C for 4 h to get phase selective product. It was observed that gelation time depends on the concentration of reactants and temperature. The characterization of ZrSnO4 was carried out with XRD, SEM, TEM, UV, thermal analysis, DLS and FT-IR techniques. With adjustment of reaction parameters, the systematic tuning of the particle size, shape and functional properties can be controlled. It was concluded that self-assembly is an integral part for the synthesis and opens a new exciting opportunity for better understanding the formation of nanostructure framework from micro- to nanoscale along with mechanistic via wet chemical approach. ZrSnO4 has vital role in identifying its potential cytotoxicity in the biological systems. The cytotoxicity effects of ZrSnO4 nanopowder in vitro were evaluated in three different human cell types (hepatocytes, mesenchymal stem cells and neuronal cells). Acute exposure of nanoparticles was found to have greater cytotoxic effect at higher concentration (30 µg/ml). However, partial detoxification was observed during nanoparticles exposure at day 6. The study concluded that an initial stress from nanoparticles incorporates sealing or detoxification of nanoparticles which may help to recover cell viability.
Keywords: Green process; Microstructure; Particle size and its distribution; Cytotoxicity; Pre-screening tests

Antimicrobial kinetics of Alstonia scholaris bark extract-mediated AgNPs by N. Supraja; T. N. V. K. V. Prasad; E. David; T. Giridhara Krishna (779-787).
Nanobiotechnology is considered as one of the important branches of nanotechnology, and research on synthesis of nanoscale materials, silver in particular, using plant and plant parts has been progressing rapidly. Herein, we used bark extract of Alstonia scholaris one of the most important medicinal plants to synthesize silver nanoparticles (AgNPs) which exhibited excellent antimicrobial properties against biofilm formed in drinking water PVC pipes. The biosynthesis of silver nanoparticles was done by treating 90 mL of 1 mM AgNO3 aqueous solution with 10 mL of 5 % bark extract. As-prepared silver nanoparticles were characterized using the biophysical techniques such as UV–Vis spectroscopy, Fourier transform infrared spectroscopy, X-ray diffraction, thermogravimetric analysis, transmission electron microscopy, and dynamic light scattering for the measurement of hydrodynamic diameter and zeta potential. The kinetics of the antimicrobial activity against PVC biofilm of prepared silver nanoparticles were done using comparative solution suspension time-killing assessments and which are evidenced in Epi-fluorescent microscopic observations.
Keywords: Alstonia scholars bark extract; Silver nanoparticles; Antimicrobial activity; Killing; Efficacy; TGA