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Chemical reduction of graphene oxide (GO) to graphene employs the use of toxic and environmentally harmful reducing agents, hindering mass production of graphene which is of tremendous technological importance. In this study we report a green approach to the synthesis of graphene, bio-reduced by crude polysaccharide. The polysaccharide reduces exfoliated GO to graphene at room temperature in an aqueous medium. Transmission electron microscopy image provides clear evidence for the formation of few layer graphene. Characterization of the resulting polysaccharide reduced GO by Raman spectroscopy, Fourier transform infrared spectroscopy and Energy dispersive X-ray analysis confirms reduction of GO to graphene. We also investigated the degree of biosafety of the reduced GO and found it to be safe under 100 μg/ml. [ABSTRACT FROM AUTHOR]

Increased incidence of antibiotic-resistant species calls for development of new types of nano-medicine that can be used for healing of bacteria-caused wounds, such as diabetic foot ulcer. As diabetic patients have inefficient defense mechanism against reactive oxygen species (ROS) produced in our body as a by-product of oxygen reduction, the process of wound healing takes longer epithelialisation period. Ceria nanoparticles (CNPs) are well-known for their antibacterial and ROS-scavenging nature. Yet till now no significant effort has been made to conjugate ceria nanoparticles with drugs to treat diabetic wounds. In this experiment, CNPs were synthesized in-house and clindamycin hydrochloride was loaded onto it by physical adsorption method for reactive oxygen species responsive drug delivery. Various physico-chemical characterisations such as Transmission electron microscopy, Fourier transform infrared spectroscopy, X-ray diffraction, Energy dispersive X-ray, Thermogravimetric study etc. were performed to affirm the formation of both nanoceria along with drug encapsulated nanoceria. Both of these as-prepared formulations inhibited the growth of Gram-positive as well as Gram-negative bacteria confirmed by Disk diffusion study; exhibiting their antibacterial effect. In-vitro drug release study was carried out in physiological environment both in absence and presence of hydrogen peroxide solution to test the reactive ROS-responsiveness of the drug loaded nanocomposites. It also exhibited faster wound healing in diabetes-induced rats. Therefore, it could successfully lower the amount of serum glucose level, inflammation cytokines, hepatotoxic and oxidative stress markers in diabetic rats as confirmed by various ex vivo tests conducted. Thus, drug loaded ceria nanoparticles have the potential to heal diabetic wounds successfully and can be considered to be useful for the fabrication of appropriate medicated suppositories beneficial for diabetic foot ulcer treatment in future. [Display omitted] • Clindamycin hydrochloride was loaded onto nanoceria (CLIN@CNP) for diabetic wound healing study. • Successful drug loading onto nanoparticles with maximum loading of ≈ 22.5%, have been confirmed by TGA and UV spectral study. • Both neat drug and CLIN@CNP impede growth of Gram-positive besides Gram-negative bacteria signifying antibacterial activity. • In-vitro drug release data validated that CLIN@CNP exhibited ROS-responsive drug delivery for diabetic wound treatment. • Ex-vivo studies also confirmed establishment of nanoceria based futuristic model for diabetic treatment successfully. [ABSTRACT FROM AUTHOR]

Graphene and its related materials are important areas of research in recent years owing to their unique properties. The wide-range industrial application of graphene-related compounds has led to the development of novel and simple methods for the synthesis of graphene. In this paper, an environmentally friendly green synthesis for the partial reduction of graphene oxide (GO) to reduced GO (RGO) in a cost-effective single-step mechanism was reported. The method completely avoids the use of toxic and environmentally harmful reducing agents commonly used in the chemical reduction of GO to obtain RGO. The reduction of GO was carried out using aqueous leaf extracts of Paederia foetide L. The prepared GO and green RGO were characterized by ultraviolet-visible, Raman and Fourier transform infra-red spectroscopic analysis which showed a clear indication of the partial removal of oxygen-containing groups from the GO and the formation of RGO. The morphology of the green RGO was characterized by transmission electron and scanning electron microscopy. Dynamic light scattering was used for zeta potential measurement and correlated with the morphology of the sheets. Electrical conductivity was also measured to check the extent of reduction of GO to RGO. [ABSTRACT FROM AUTHOR]

Bile salts carry out a vital bioactive responsibility among the various physiologically important molecules. The use of bile acids and their conjugates in nanoscience is a novel idea, which opens up fascinating prospects and gives rise to various versatile properties. Sodium cholate, a biosurfactant which is environmentally safe, has been used to reduce and stabilize silver nitrate solution. The silver nanostructures thus produced are crystalline and anisotropic in nature and show different types of particle shapes and sizes depending on the reaction conditions including star and wire shapes which have not been reported earlier, by simply varying the reaction conditions. The silver precursor concentration and the ratio of sodium cholate to silver precursor were the key factors which controlled the morphosynthesis. The formation of the silver NPs was monitored using UV-vis spectrophotometry. The transmission electron microscopy (TEM) technique was used to study the morphology of the synthesized NPs. Fourier transform infrared (FT-IR) spectroscopy was used to identify the interaction of sodium cholate with the synthesized NP. The possible mechanistic role of sodium cholate in the reduction and stabilization of silver nanoparticles (Ag NPs) has also been discussed. The obtained Ag NPs exhibit antibacterial and anticancerous activities. The present study also explores the cytotoxic role of Ag NPs in KG-1A (human acute myeloid leukemia) and K562 (human chronic myeloid leukemia) cell lines. [ABSTRACT FROM AUTHOR]

A rapid polymerization technique was successfully employed to synthesize interconnected polyaniline ( PANI) nanofibers using chemical oxidative polymerization inside a soft template. The thermoreversible hydrogels of Lutrol F 127 and gelatin were used as templates where the interstices present in the hydrogel were responsible for the formation of PANI nanofibers with a diameter in the range ca 70−75 nm and ca 50−55 nm respectively and several micrometers in length. The doped emeraldine salt of PANI was confirmed by Fourier transform infrared spectroscopy and ultraviolet-visible spectroscopy. The crystallinity of as-synthesized PANI nanofibers for both cases was verified by an X-ray diffraction study while thermogravimetric analysis was performed to compare the relative stability of the synthesized PANI nanofibers. The electrical conductivities of polymerized PANI are of the order of 10−3 S cm−1 and are compared with those of template fabricated PANI. The Lutrol F 127 gel guided PANI nanofibers showed a rectifying property while the gelatin gel guided PANI provided a simple ohmic nature. © 2013 Society of Chemical Industry [ABSTRACT FROM AUTHOR]

Polyaniline (PANI)-Ag nanocomposites were synthesized by in situ chemical polymerization approach using ammonium persulfate and silver nitrate as oxidant. Characterizations of nanocomposites were done by ultraviolet-visible (UV-vis), Fourier transform infrared (FTIR), X-ray diffraction (XRD), scanning electron microscopy, and transmission electron microscopy (TEM). UV-vis, XRD and FTIR analysis established the formation of PANI/Ag nanocomposites and face-centered-cubic phase of silver. PANInanofibers were of average diameter ∼ 30 nm and several micrometers in length. Morphological analysis showed that the spherical-shaped silver nanoparticles decorate the surface of PANI nanofibers. Silver nanoparticles of average diameter ∼ 5-10 nm were observed on the TEM images for the PANI-Ag nanocomposites. Such type of PANI-Ag nanocomposites can be used as bistable switches as well as memory devices. © 2013 Wiley Periodicals, Inc. J. Appl. Polym. Sci., 2013 [ABSTRACT FROM AUTHOR]

In the present article we describe a facile biosynthetic method for the silver nanoparticles highlighting myconanotechnology and its antimicrobial efficacy. The nanoparticles were characterized using UV-vis spectroscopy, dynamic light scattering (DLS), transmission electron microscopy (TEM), atomic force microscopy (AFM), X-ray diffraction (XRD) and fourior transform infrared (FTIR) spectroscopy. These methods allow validating the spherical nature of the produced nanoparticles ranging from 30 nm to ∼90 nm in size. The crystallinity of the nanoparticles was confirmed by XRD. The probable mechanistic aspect for the mycogenesis of the silver nanoparticles are also evaluated which would facilitate for several industrial applications based on potential antimicrobials. [ABSTRACT FROM AUTHOR]

In the modern environment conscious era, there has been a huge demand for the effective green method to fabricate biomaterials for sustained transdermal release of diltiazem hydrochloride to treat hypertension and cardiac failure. In this vein, the present study explores the amination of waste jute sourced nanocellulose (ANC) and its effect as a reinforcing filler to design electrospun polyvinyl alcohol (PVA)/chitosan based polymeric nanofibrous scaffold for drug delivery. The characterization results of FTIR (Fourier Transform Infrared Spectroscopy) confirm the successful chemical modification of nanocellulose (NCC). SEM (Scanning Electron Microscopy) results indicate the morphological modifications in ANC due to grafting. ANC enhances the mechanical properties of scaffold and sustains the release of the loaded drug to 67.89 ± 3.39 % as compared to the pure PVA/chitosan scaffold of 92.63 ± 4.63 % over a period of 72 h as shown by the results of in-vitro drug release study. Moreover, the incorporation of 0.5 % ANC improves the anti-bacterial activity against both gram-positive (97.4 ± 4.87 % , reduction in viable cells count) and gram-negative bacteria (98.5 ± 4.93 % , reduction in viable cells count). Further, the skin irritation and MTT assay authenticate the biocompatibility of the developed scaffold. The overall findings hence prove the efficacy of the engineered scaffold as a potential transdermal patch for sustained drug delivery applications. [Display omitted] [ABSTRACT FROM AUTHOR]

Abstract A green, efficient synthesis of cadmium oxide decorated reduced graphene oxide nanocomposites (RGO/CdO) was prepared by one-step co-precipitation and hydrothermal method. Crystalline nature of the nanocomposites was characterized by X-ray diffraction analysis. To evaluate the structural morphology and particle size, high resolution transmission electron microscopy were used. X-ray photoelectron spectroscopy, Raman spectroscopy and Fourier transform infrared spectroscopy techniques were employed to establish chemical structure of the nanocomposites and Atomic Force Microscopy was done to measure the thickness. The optical properties were evaluated by UV–visible absorption spectroscopy. Thermo-gravimetric analysis, BET surface area and zeta potential measurements were carried out to study the thermal and surface characteristics. The CdO nano-particles (NPs) decorated on RGO sheets exhibit better electrical conductivity compared to RGO. The antibacterial activity of the nanocomposites has also been monitored in different culture media imparting good potentiality than RGO. Graphical abstract Unlabelled Image Highlights • RGO/CdO nanocomposite was successfully synthesized by adopting green route. • Dextrose acts as reducing and stabilizing agent which is nontoxic, low cost and easily available. • The electrical conductivity of the nanocomposite is higher than RGO. • The antibacterial property of the nanocomposite imparting good potentiality compared to RGO [ABSTRACT FROM AUTHOR]

In this work, we report the development of a cross-linked bio-composite consisting of graphene oxide, potato starch, cross-linker glutaraldehyde and its application to adsorption of the industrial dye, methylene blue, from aqueous solution. The inexpensiveness, non-hazardous nature and easy bio-degradability are the major reasons for the selection of starch material as one of the components of the bio-composite. The bio-composite has been characterized by FTIR, SEM, XRD, particle size and zeta potential analysis. The FTIR analysis reveals the nature of the binding sites and surface morphology of the bio-composite can be understood through SEM. The auto-phase separability of the adsorbent i.e., the precipitation of the adsorbent without any mechanical means is another factor which makes this particular material very attractive as an adsorbent. Parameters like adsorbent dosage, pH, temperature, rotation speed and salt concentration have been varied to find out the suitable dye adsorption conditions. Furthermore, the time dependence of adsorption process has been analyzed using pseudo-first and pseudo-second order kinetics. The adsorption isotherms have been constructed to suggest convincing mechanistic pathway for this adsorption process. Finally, desorption studies have been successfully performed in 3 cycles, establishing the reusability of the material, which should allow the adsorbent to be economically promising for practical application in wastewater treatment. [ABSTRACT FROM AUTHOR]

The delivery of diltiazem hydrochloride in therapeutical doses has attracted an immense research interest. However, its slower penetration through the transdermal route has stipulated to develop a competent transdermal membrane. Therefore, a nanocomposite based patch was formulated by exploring co-polymer and jute derived nano-cellulose. Poly( N -isopropylacrylamide) was grafted into guar gum (GG- g -PNIPAAm) with different feeding ratios. The co-polymer formation was authenticated by FTIR and 13C NMR spectra. The nanocomposite were prepared by incorporating nanofibre (0.5–2 wt%) into GG- g -PNIPAAm. The structural and morphological studies supported good interactions and presence of nano-cellulose on co-polymer. GG- g -PNIPAAm has showed higher thermostability than guar gum. Moreover, the addition of CNF has improved the thermo-mechanical and barrier properties of the nanocomposite. The nanocomposite containing 1 wt% CNF was found to be best performing. The patch showed in-vitro cyto-compatibility and non-irritant behaviour. The in-vitro release study of best nanocomposite revealed controlled drug release capability with 7.78 and 22.9% after 5 and 20 h, respectively. [ABSTRACT FROM AUTHOR]

The effect of gellan gum on the gelation behavior and in-vitro release of a specific drug named pilocarpine hydrochloride from different ophthalmic formulations based on poloxamer 407 is examined. The mixture of 0.3 wt% gellan gum and 18 wt% poloxamer (PM) solutions show a considerable increase in gel strength in physiological condition. Gel dissolution rate from PM based formulation is significantly decreased due to the addition of gellan gum. FTIR spectra analysis witnesses an interaction in between OH groups of two polymers which accounts for lowering in gelation temperature of PM-gellan gum based formulations. It is also observed from the cryo-SEM study that the pore size of PM gel decreases with an addition of gellan gum and in-vitro release studies indicate that PM-gellan gum based formulation retain drug better than the PM solution alone. Therefore, the developed formulation has the potential to be utilized as an in-situ ophthalmic drug carrier. [ABSTRACT FROM AUTHOR]

This study sought to detect the presence of sucrose as an adulterant in selected honey varieties from different floral origins by employing Electrical Impedance Spectroscopy (EIS) technique which has been simultaneously supported by Fourier Transform-Mid Infrared Spectroscopy (FT-MIR) measurements to provide a rapid, robust yet simple platform for honey quality evaluation. Variation of electrical parameters such as impedance, capacitance and conductance for 10%, 20%, 30%, 40%, 50%, 60% and 70% (w/w) sucrose syrup (SS) adulterated honey samples are analyzed and their respective current-voltage (I-V) characteristics are studied. Capacitance, conductance and net current flowing through the system are observed to decrease linearly whereas system impedance has been found to increase similarly with the increase in adulterant content. Also, FT-MIR measurements in the spectral region between 1800 cm −1 and 650 cm −1 reveal the increment of absorbance values due to the addition of SS. Full-Width-at-Half-Maximum (FWHM) is estimated from the spectral peak 1056 cm −1 for all pure and adulterated honey samples and is observed to be linearly increasing with increase in adulterant content. Finally, the coefficient of sensitivity has been extracted for all varieties of honey considered in terms of the measured conductance values. [ABSTRACT FROM AUTHOR]

Proflavine, a nitrogen-containing dye is used for DNA staining and as an efficient marker, however, it is harmful to body cells, and its efficient removal is essential. In this work, graphene oxide (GO) has been used as an adsorbent for the removal of the dye through the process of adsorption. Though GO is now being used as an adsorbent for the removal of industrial dyes, very few experiments have been done on biologically useful dyes. GO is synthesized from graphite powder by the modified Hummer's method and is characterized by X-ray diffraction, Fourier transform infrared spectroscopy (FTIR), Raman and ultra-violet spectroscopies, etc. These characterization techniques indicate the presence of oxygen containing functional groups, e.g., carbonyl, carboxyl and hydroxyl groups on the graphene sheets. These sheets are held well apart by these groups. Parameters like concentration of the adsorbent, pH and temperature have been varied to find the optimum conditions for the most efficient removal of the dye molecules from the solution. Then, for the optimum external conditions, the time dependence of the adsorption was analyzed using pseudo-first and pseudo-second orders kinetics. The adsorption isotherms were also obtaining throws light on the mechanism of the adsorption process which we investigated further by using FTIR characterization. [ABSTRACT FROM AUTHOR]

Highlights: [•] Formation of GO is confirmed by XRD, FTIR and Raman spectral analysis. [•] HPMC/GO nanocomposites are developed. [•] XRD and SEM establish the formation of exfoliated HPMC/GO nanocomposites. [•] Enhancements in mechanical and thermal properties of nanocomposites are observed. [•] Moisture absorption and WVTR of HPMC film are declined with GO loading. [ABSTRACT FROM AUTHOR]

An environment-friendly approach for the synthesis of reduced graphene oxide/nickel oxide nanocomposites (RGO/NiO NCs) was done in a microwave via in-situ co-precipitation and hydrothermal mode. A non-toxic aqueous phytoextract was used as a reducing cum stabilizing agent. X-ray diffraction, Raman spectra, Fourier transform infrared spectroscopy analysis confirmed the chemical structure of the NCs. The morphological studies were investigated by scanning electron microscopy, high resolution transmission electron microscopy and energy disperse X-ray. The optical study was verified by UV–visible absorption spectroscopy. The photo-degradation activity was performed at visible light by exposing the methylene blue (MB) dye solution along with the NCs. Experimental result reveals the improved photo-catalytic activity of the NCs towards the photo-degradation of MB (93%) compare to pure NiO NPs (65%) and RGO (negligible). In the nanocomposites, the electronic charge transfer takes place superficially from NiO nanoparticles (NPs) to RGO, effectively delays the electron-hole pair (e − -h + ) recombination effect and increases the decomposition rate of the dye solution to some greater extent. The antibacterial activity of the NCs shows impressive potentiality in different culture media contrast with its constituent. • ➢ One step in-situ RGO/NiO nanocomposites has been synthesized adopting green route. • Psidium guajava L (guava) leaf extract is used as green reducing agent which is low cost and eco-friendly. • The nanocomposites shows better photocatalytic activity compared to NiO NPs and RGO. • Antibacterial activity of the nanocomposites is enhanced with respect to RGO and NiO NPs. [ABSTRACT FROM AUTHOR]