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The development of environmentally acceptable benign techniques using purely natural methods is a cost-effective procedure with long-term benefits in all areas. With this consideration, myco synthesized silver nano particles (AgNPs) were studied and it acted as an impending corrosion inhibitor in the environment. Initially, AgNPs was evaluated by physical and surface characterizations and this evidence demonstrated that RYRE's water-soluble molecules played an essential role in the synthesis of AgNPs in nano spherical size. The myco synthesized of AgNPs has showed an antibacterial activity against corrosive bacteria in Cooling Water System (CWS). Hence, the AgNPs were used in biocorrosion studies as an anticorrosive agent along with AgNO3 and RYRE was also checked. For this experiment, the copper (Cu) metal (CW024) which is commonly used was selected, the result of corrosion rate was decreased and inhibition efficiency (82%) was higher in the presence of AgNPs in system IV. Even though, AgNO3 and RYRE had contributed significant inhibition efficiency on Cu at 47% and 61% respectively. According to XRD, the reaction of AgNPs on Cu metal resulted in the formation of a protective coating of Fe2O3 against corrosion. EIS data also indicated that it could reduce the corrosion on the Cu metal surface. All of these findings point out the possibility that the myco synthesized AgNPs were an effective copper metal corrosion inhibitor. As a result, we encourage the development of myco-synthesized AgNPs, which could be useful in the industrial settings.

A simple, cost effective and eco-friendly silver nanoparticle (AgNPs) was synthesized by wild edible Macrolepiota mushroom. Nanoparticles were characterized by UV-visible, FTIR, XRD analysis and TEM analysis. The characterized studies confirmed the spherical shape of AgNPs with 20-50 nm size. Biocorrosion efficacy of myco-synthesized AgNPs and the mushroom extract were tested against mild steel by corrosive bacteria Bacillus thuringiensis EN2, Terribacillus aidingensis EN3 and Bacillus oleronius EN9. Weight loss analysis, EIS, and surface analysis were used to evaluate the corrosion inhibition efficiency of mild steel in various experimental systems. Reduced corrosion rate (0.07 mm/y, 0.14 mm/y), reduced weight loss (0.006 ± 2, 0.011 ± 2) and increased corrosion inhibition efficiency (59%, 18%) were identified in both system II and system IV. Peak intensity was reduced in both surface analysis studies (FTIR and XRD) in the presence of mushroom extract and AgNPs. EIS studies reveal that the mushroom extract and AgNPs act as a corrosive green inhibitor and adsorbs on the mild steel surfaces in cooling water tower system, which are responsible for corrosion protection.

The deployment of biological resources for the synthesis of nanoparticles of metals and metal oxides is the latest addition to green chemistry. The present work describes the use of aqueous stem extracts of Aristolochia indica and Indigofera tinctoria for the synthesis of silver and gold nanoparticles (Ag and Au NPs). The synthesized NPs were characterized by UV–Vis., FT-IR, TEM, XRD and EDAX analyzes. The antioxidant activities of functionalized Ag and Au NPs were studied by the DPPH method and the nanoparticles showed greater antioxidant activity than that of the extract; AgNPs synthesized by A. indica showed antioxidant activity of 84%. The in vitro cytotoxicity of the Ag and Au NPs was assessed by the MTT assay method using the HeLa cell line and the NPs synthesized by A. indica showed nearly 100% toxicity. DNA binding capacity was investigated using calf thymus-DNA by UV–Vis spectra, the hyperchromism shift inferred the groove binding of nanoparticles and the binding constants (1.66 × 107 and 1.06 × 107 and 0.77 × 107 and 1.59 × 107 M−1 for the NPs of Ag and Au synthesized by A. indica and I. tinctoria respectively) indicate a high potential of these nanoparticles for the administration of drugs.

Methanolic extract of Artemisia pallens (MEAP) (Asteraceae) was explored as greenbiocorrosion inhibitor for mild steel 1010 in 1.5% sodium chloride environment. Bacillus megaterium SKR7 induces the development of biofilm on the metal surface and forms the pitting corrosion. MEAP was showed (25 ppm) optimum inhibition effect of biocorrosion and further corrosion rate was highly reduced (0.3335 mm/year) than the control system (0.009 mm/year). The electrochemical study has supported the results with a higher value of total resistance (34 Ω cm2) when compared to control systems. It reveals the formation of a protective layer on the metal surface and reduces the adsorption of biofilm. This was due to the antimicrobial effect of MEAP. Overall, the results recognized that MEAP used as a green corrosion inhibitor for MS 1010 with 83% inhibition efficiency.

Pristine ZrO2 and molar ratios of Cu-doped ZrO2 nanoparticles were synthesized by chemical precipitation. The XRD pattern of pristine ZrO2 and Cu-doped ZrO2 nanoparticles shows the formation of t-tetragonal phase and shifting of tetragonal phase to monoclinic phase. The average crystallite sizes of the pristine ZrO2 and Cu-doped ZrO2 nanoparticles were calculated as 2.9, 4.65, 4.76, 5.02, and 4.96 nm, respectively. The Cu (0.06 M)-doped ZrO2 nanoparticles are present as spherical morphology and high agglomeration was confirmed by FE-SEM and TEM analyses. The XPS spectra affirmed the presence of Cu2+, Zr4+, and oxygen ions in the Cu (0.06 M)-doped ZrO2 nanoparticles. The Cu-doped ZrO2 nanoparticles exhibit two energy gaps at 5.30 and 3.05 eV, 5.21 and 2.22 eV, 4.65 and 2.11 eV, and 4.44 and 2.65 eV. The surface defects and oxygen vacancies were analyzed by PL and ESR spectroscopy. The ESR spectra are clearly asymmetric in shape and contain a peak signal related to the presence of the copper species (Cu2+) in the distorted tetragonal coordination of ZrO2. The photocatalytic activities of Cu (0.06 M)-doped ZrO2 nanoparticles were successfully sought on degradation of the two azo dyes: methyl violet and methyl blue under sunlight irradiation. Cu (0.06 M)-doped ZrO2 showed complete degradation at 70 min. The reusability of Cu (0.06 M)-doped ZrO2 nanoparticles shows maximum degradation efficiency for six successive runs.

This paper reports the preparation of composite CuO/ZnO nanoparticles by facile precipitation route and their photocatalytic activity against organic dyes. The red shift caused in the UV–Vis absorption spectrum suggests the enhancement of visible light photocatalytic activity of the material. The collective vibrations of Cu–O and Zn–O in FTIR spectrum clearly illustrate the formation of composite CuO/ZnO nanoparticles. Powder XRD profile suggests the formation of highly crystalline material and the chemical states of the elements is investigated by XPS analysis. A slightly agglomerated cluster-like structure of the particles is visualized by SEM analysis and EDS mapping illustrates the homogeneous distribution of the sample, which is most favorable for the photocatalysis analysis. The photocatalytic activity of material is studied against degradation of Rhodamine B and Methylene blue dyes using simulated solar light irradiation. The dielectric analysis of the composite CuO/ZnO nanoparticles demonstrates the enhanced dielectric permittivity and low loss factor in comparison with pure CuO and ZnO nanoparticles.

In this paper, the spectral and electrical properties of a conjugated polymer poly [(9, 9-dioctyl-2, 7-divinylenefluorenylene)-alt-co-(1, 4-phenylene)] (PFO–MEH–PPV) with poly[3-(2-ethyl-isocyanato-octadecanyl) thiophene] (PECOD) in thin films have been studied. First, PFO–MEH–PPV and PECOD were dissolved in tetrahydrofuran and chloroform respectively for different concentrations. These solutions were deposited on glass substrates to form thin films with different thicknesses. The absorbance and photoluminescence spectra for each individual pure polymer were recorded and contrasted with those for blended conjugated polymer’s films to determine the effect of blending on the absorption and photoluminescence. Finally, we present a study on the processing and characterization of organic solar cells fabricated by spin coating pure PFO–MEH–PPV, PECOD and their blend as the organic active layer onto indium tin oxide layer (150 nm), followed by the evaporation of silver cathode (110 nm). The current–voltage characteristics of these cells were determined and external quantum efficiency. Upon blending the two polymers in solid forms, it could be seen that the efficiency (6.25%) for the cells based on a blend layer is higher than the ones without blending (4.4%). Finally, we demonstrated here that the combination/blending of conjugated polymers has resulted in optimized solar device function, with reasonably quantum efficiency higher than 10%.

A hybrid and straightforward nanosystem that can be used simultaneously for cancer-targeted fluorescence imaging and targeted drug delivery in vitro was reported in this study. A chitosan (CS) polymer coated with reduced graphene oxide (rGO) and implanted with Fe3O4 nanoparticles was fabricated. The fundamental physicochemical properties were confirmed via FT-IR, XRD, FE-SEM, HR-TEM, XPS, and VSM analysis. The in vivo toxicity study in zebrafish showed that the nanocomposite was not toxic. The in vitro drug loading amount was 0.448 mg/mL−1 for doxorubicin, an anticancer therapeutic, in the rGO/Fe3O4/CS nanocomposite. Furthermore, the pH-regulated release was observed using folic acid. Cellular uptake and multimodal imaging revealed the benefit of the folic acid-conjugated nanocomposite as a drug carrier, which remarkably improves the doxorubicin accumulation inside the cancer cells over-express folate receptors. The rGO/Fe3O4/CS nanocomposite showed enhanced antibiofilm and antioxidant properties compared to other materials. This study's outcomes support the use of the nanocomposite in targeted chemotherapy and the potential applications in the polymer, cosmetic, biomedical, and food industries.

Hybrid nanocomposites can offer a wide range of opportunities to control the light-matter interac- tion and electromagnetic energy flow at the nanoscale, leading to exotic optoelectronic devices. We study theoretically the dipole-dipole interaction in noble metal nanoparticles-graphene nanodisks- quantum dots hybrid systems in the optical region of the electromagnetic spectrum. The quantum dot is assumed to be a three-level atom interacting with ultrashort control and probe pulses in a Lambda configuration. The dynamics of the system are studied by numerically solving for the time evo- lution of the density matrix elements. We investigate the rate of energy exchange between surface plasmon resonances of the graphene nanodisks and excitons of the quantum dots in the presence of metal nanoparticles at steady state and for specific geometrical conditions of the system. Ultrafast population dynamics are obtained with a large energy exchange rate significantly depending on the size of metal nanoparticles. The power transfer can be controlled by varying the center-to-center distances between the components of the system, and their positions with respect to each other. We also find that the rate of energy transfer within the system is governed by the probe field Rabi frequency, enhanced by the dipole-dipole interaction., Comment: 8 pages and 6 figures

Nanocrystalline nickel ferrite spinel, NiFe2O4, with average crystallite size of 23.98 and 19.76 nm were successfully synthesized under sol–gel method (SGM) and microwave method (MM) conditions without using any surfactant or otherwise structure-directing (oxalic acid as the fuel) agents. Powder x-ray diffraction, high-resolution scanning electron microscopies indicate that single-crystalline nanoparticles are well-dispersed in the nickel ferrite. The elemental investigation of nickel ferrite was attained from energy-dispersive x-ray (EDX) analysis. Their optical properties (diffuse reflectance spectroscopy and photoluminescence) were described in depth in relative with their structural characteristics and the functionalization performance. After the magnetic measurements, samples showed a ferromagnetic behavior and the magnetization (Ms) value of NiFe2O4-MM is higher, i.e., 59.33 emu/g than NiFe2O4-SGM (50.12 emu/g). The magnetic properties could be further changed by controlling the shape, size, and crystallinity of the nanocrystals. Determination of concentration NiFe2O4 ions’ average number of atoms per nanoparticle was calculated by the new method as follows. Consequently, the designated procedure improves catalytic activity of nickel ferrite powders in aerobic oxidation of benzyl alcohol and catalytic reactions.

Mosquitoes represent a key threat for millions of humans worldwide, since they act as vectors for malaria, dengue fever, yellow fever, Zika virus, filariasis, and encephalitis. In this study, we tested chitosan-synthesized silver nanoparticles (Ch–AgNP) using male crab shells as a source of chitosan, which acted as a reducing and capping agent. Ch–AgNP were characterized by UV–Vis spectroscopy, FTIR, SEM, EDX, and XRD. Chitosan and Ch–AgNP were tested against larvae and pupae of the malaria vector Anopheles sundaicus under laboratory and field conditions. Antibacterial properties of Ch–AgNP were tested on Bacillus subtilis, Escherichia coli, Klebsiella pneumoniae, and Proteus vulgaris using the agar disk diffusion assay. The standard predation efficiency of the mosquito natural enemy Carassius auratus in laboratory conditions was 60.80 (on larva II) and 19.68 individuals (on larva III) per day, while post-treatment with sub-lethal doses of Ch–AgNP, the predation efficiency was boosted to 72.00 (on larva II) and 25.80 individuals (on larva III). Overall, Ch–AgNP fabricated using chitosan extracted from the male crab shells of the hydrothermal vent species Xenograpsus testudinatus may offer a novel and safer control strategy against A. sundaicus mosquito vectors, as well as against Gram-negative and Gram-positive pathogenic bacteria.

In this research we focused on the green synthesis of silver nanoparticles (AgNPs) using Pimpinella anisum seed extract. Furthermore, we evaluated their cytotoxicity on colorectal cancer (CRC) cell lines. Our results revealed the anti-cancerous cytotoxic potential of green synthesized AgNPs. Green synthesized AgNPs exhibited high cytotoxicity on colorectal adenocarcinoma CRC cells. They selectively killed cancer cells through suppression of proliferation, cell cycle arrest at the G2/M phase, and induction of apoptosis. Interestingly, between the two different clones, SW620 cells were more sensitive than HCT8 cells. Overall, our findings suggest that AgNPs could be effective cancer chemotherapeutic agents or a combination nano-drug in future anti-cancer therapy.

A main challenge in parasitology is the development of reliable tools to prevent or treat mosquito-borne diseases. We investigated the toxicity of magnetic nanoparticles (MNP) produced by Magnetospirillum gryphiswaldense (strain MSR-1) on chloroquine-resistant (CQ-r) and sensitive (CQ-s) Plasmodium falciparum, dengue virus (DEN-2), and two of their main vectors, Anopheles stephensi and Aedes aegypti, respectively. MNP were studied by Fourier-transform infrared spectroscopy and transmission electron microscopy. They were toxic to larvae and pupae of An. stephensi, LC50 ranged from 2.563 ppm (1st instar larva) to 6.430 ppm (pupa), and Ae. aegypti, LC50 ranged from 3.231 ppm (1st instar larva) to 7.545 ppm (pupa). MNP IC50 on P. falciparum were 83.32 μg ml−1 (CQ-s) and 87.47 μg ml−1 (CQ-r). However, the in vivo efficacy of MNP on Plasmodium berghei was low if compared to CQ-based treatments. Moderate cytotoxicity was detected on Vero cells post-treatment with MNP doses lower than 4 μg ml−1. MNP evaluated at 2–8 μg ml−1 inhibited DEN-2 replication inhibiting the expression of the envelope (E) protein. In conclusion, our findings represent the first report about the use of MNP in medical and veterinary entomology, proposing them as suitable materials to develop reliable tools to combat mosquito-borne diseases.

This article was aimed to extend a simple procedure for the preparation by a sol-gel method by using iron nitrate and polar solvent (e.g., water) as the starting materials from the viewpoint that they are of low cost. A study of the effect of chelating agents such as citric acid weight ratio on the structure of Fe3O4 was reported. The synthesized product was characterized by powder X-ray diffraction (XRD), high-resolution scanning electron microscopy (HR-SEM), high-resolution transmission electron microscopy (HR-TEM), photoluminescence (PL) studies, and vibrating sample magnetometer (VSM). Magnetic analysis revealed that the Fe3O4 nanoparticles had a ferromagnetic behavior at room temperature with a saturation magnetization of 20.83 emu/g. Furthermore, Fe3O4 nanoparticles prepared by the sol-gel method using citric acid were tested for the catalytic activity towards the oxidation of benzyl alcohol.

Mosquitoes are vectors of devastating pathogens and parasites, causing millions of deaths every year. Dengue is a mosquito-borne viral infection found in tropical and subtropical regions around the world. Recently, dengue transmission has strongly increased in urban and semiurban areas, becoming a major international public health concern. Aedes aegypti (Diptera: Culicidae) is a primary vector of dengue. Shedding light on genetic deviation in A. aegypti populations is of crucial importance to fully understand their molecular ecology and evolution. In this research, haplotype and genetic analyses were conducted using individuals of A. aegypti from 31 localities in the north, southeast, northeast and central regions of Tamil Nadu (South India). The mitochondrial DNA region of cytochrome c oxidase 1 (CO1) gene was used as marker for the analyses. Thirty-one haplotypes sequences were submitted to GenBank and authenticated. The complete haplotype set included 64 haplotypes from various geographical regions clustered into three groups (lineages) separated by three fixed mutational steps, suggesting that the South Indian Ae. aegypti populations were pooled and are linked with West Africa, Columbian and Southeast Asian lineages. The genetic and haplotype diversity was low, indicating reduced gene flow among close populations of the vector, due to geographical barriers such as water bodies. Lastly, the negative values for neutrality tests indicated a bottle-neck effect and supported for low frequency of polymorphism among the haplotypes. Overall, our results add basic knowledge to molecular ecology of the dengue vector A. aegypti, providing the first evidence for multiple introductions of Ae. aegypti populations from Columbia and West Africa in South India.

Mosquitoes (Diptera: Culicidae) are a key threat for millions of people worldwide, since they act as vectors for devastating pathogens and parasites. The standard method of utilisation of morphological characters becomes challenging due to various factors such as phenotypical variations. We explored the complementary approach of CO1 gene-based identification, analysing ten species of mosquito vectors belonging to three genera, Aedes, Culex and Anopheles from India. Analysed nucleotide sequences were found without pseudo genes and indels; they match with high similarity in nucleotide Basic Local Alignment Search Tool (BLASTn) search. The partial CO1 sequence of Anopheles niligricus was the first time record submitted to National Center for Biotechnology Information (NCBI). Mean intra- and interspecies divergence was found to be 1.30 and 3.83 %, respectively. The congeneric divergence was three times higher than the conspecifics. Deep intraspecific divergence was noted in three of the species, and the reason could be explained more accurately in the future by improving the sample size across different locations. The transitional and transversional substitutions were tested individually. Ts and Tv substitutions in all the 1st, 2nd and 3rd codons were estimated to be (0.44, 99.51), (40.35, 59.66) and (59.16, 40.84), respectively. Saturation of the sequences was resolved, since both the Ts and Tv exhibited a linear relationship suggesting that the sequences were not saturated. NJ and ML tree analysis showed that the individuals of the same species clustered together based on the CO1 sequence similarity, regardless of their collection site and geographic location. Overall, this study adds basic knowledge to molecular evolution of mosquito vectors of medical and veterinary importance and may be useful to improve biotechnological tools employed in Culicidae control programmes.

Pure and Co-doped ZnO nanostructured samples have been synthesized by a chemical route. We have studied the structural and optical properties of the samples by using X-ray diffraction (XRD), field-emission scanning electron microscopy (FESEM), field-emission transmission electron microscope (FETEM), energy-dispersive X-ray (EDX) analysis and UV–VIS spectroscopy. The XRD patterns show that all the samples are hexagonal wurtzite structures. Changes in crystallite size due to mechanical activation were also determined from X-ray measurements. These results were correlated with changes in particle size followed by SEM and TEM. The average crystallite sizes obtained from XRD were between 20 to 25 nm. The TEM images showed the average particle size of undoped ZnO nanostructure was about 20 nm whereas the smallest average grain size at 3% Co was about 15 nm. Optical parameters such as absorption coefficient (α), energy band gap (E g ), the refractive index (n), and dielectric constants (σ) have been determined using different methods.

Background Malaria is the most common disease transmitted by the bite by an infected female anopheles mosquito and caused by the plasmodium parasite. It is mostly prevalent in subtropical regions receiving abundant rain and supporting copious mosquito breeding. This disease is generally detected by the microscopic examination of blood films or antigen based rapid diagnostic test. Only occasionally the parasite DNA is detected using polymerase chain reaction in certain advanced, expensive laboratories. Methods An innovative spectral detection method based on the fluorescence spectra of a set of blood plasma biomolecules [tyrosine, tryptophan, nicotinamide adenine dinucleotide (NAD), and flavin adenine dinucleotide (FAD)] and red blood cell (RBC)-associated porphyrin is being evolved by our group. Results The research so far has exhibited sensitivity and specificity values exceeding 90% based on the spectral features of blood components of 14 malaria patients and 20 numbers of age adjusted normal controls. The fluorescent biomolecules go out of proportion when the malarial parasite breaks down the hemoglobin of blood. Conclusion This technique has the potential to be used as an alternative diagnostic procedure for malaria since the instrumentation involved is portable and inexpensive. Virtual Slides The virtual slide(s) for this article can be found here: http://www.diagnosticpathology.diagnomx.eu/vs/13000_2014_182