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The article describes the synthesis of copper oxide decorated amine functionalized graphene oxide (AGO) composites at four different temperatures, i.e., 50, 85, 120, and 155 °C. The process involves the generation of AGO by chemical functionalization and using −NH2groups to anchor Cu2+ions via coordinate bonds. Reduction of Cu2+results in Cu+on the surface of AGO, which is confirmed by XRD and TEM. The surface composition and amine functionalization of nanocomposites were confirmed by XPS and FTIR analyses. The dielectric measurements display a decrease in dielectric constant with an increase in frequency, for all nanocomposites, signifying better capacitive behavior owing to better polarization. AGC85 displays ultrahigh specific capacitance and energy density values of ∼3890 F/g and 540.71 Wh·kg–1at 2.0 A/g current density. Interestingly, after 10000 cycles, AGC85 shows excellent capacitance retention of about 85.6%. A solid state supercapacitor device was fabricated with AGC85 (active material), which can supply power for running an LED bulb for 60 min prior to a few minutes of charging. The low-temperature synthesized copper nanoparticle intercalated on amine-functionalized graphene oxide can be scaled up and used in high-performance supercapacitors for real-life applications in energy systems.

Ethanol is a colorless, highly flammable, volatile organic compound and is a biomarker for fatty liver diseases. So, high-performance and reliable ethanol sensors are the need of the day for biomedical and environmental monitoring applications and drunken driving detection. In this work, we have reported a polypyrrole (PPy)-embedded α-MnO2nanorod (NR)-based chemiresistive sensor for the selective detection of trace ethanol vapor at room temperature (25 °C). PPy-embedded α-MnO2NR nanocomposites (MP25, MP50, and MP100) were synthesized by in situ chemical oxidative polymerization of pyrrole followed by mixing of α-MnO2NR having different weight ratios. The prepared nanocomposites were characterized by various sophisticated instruments such as XRD, FTIR, Raman spectroscopy, BET, FESEM, TEM, EDX, UV–vis spectroscopy, and current–voltage (I–V) measurement. The as-prepared sensor, namely, PPy-embedded α-MnO2nanorod (MP50), shows the highest response to ethanol vapor with a detection lower limit of 1 ppm at room temperature with rapid response (∼2.39 s) and recovery (∼37.08 s) times associated with at least 60 days stability, excellent selectivity, good repeatability, and reproducibility. The formation of a p–n heterojunction and transfer of charge carriers between PPy and MnO2nanoparticles are attributed to the enhancement of sensing performance. Thus, the prepared sensor could be potentially applicable to detect ethanol content in alcoholic beverages, diagnose liver disease from exhale breath analysis, and drunken driving detection.

In this work, a novel electrochemical immunosensor based on nitrogen doped graphene quantum dot (N-GQD) and single-walled carbon nanohorns (SWCNHs) was developed for the detection of α-fetoprotein (AFP), a cancer biomarker. Thus, to fabricate the platform of the immunosensor, nanocomposite architecture was developed by decorating N-GQD on the surface of the SWCNHs. The resulting hybrid architecture (N-GQD@SWCNHs) functioned as an exceptional base for the immobilization of antibody (Anti-AFP) through carbodiimide reaction with good stability and bioactivity. The immunosensor was prepared by evenly distributing the bioconjugates (N-GQD@SWCNHs/Anti-AFP) dispersion on the surface of the glassy carbon electrode, and subsequently blocking the remaining active sites by bovine serum albumin to prevent the nonspecific adsorption. Cyclic voltammetry and electrochemical impedance spectroscopy technique was employed to investigate the assembly process of the immunosensor. Under optimal conditions, the immunosensor exhibited a broad dynamic range in between 0.001 ng/mL to 200 ng/mL and a low detection limit of 0.25 pg/mL. Furthermore, the sensor showed high selectivity, desirable stability, and reproducibility. Measurements of AFP in human serum gave outstanding recovery within 99.2% and 102.1%. Thus, this investigation and the amplification strategy exhibited a potential role of the developed nanocomposite based sensor for early clinical screening of cancer biomarkers.

Here, we reported a unique twisted rod‐like nano‐architecture of as‐synthesized 4‐fluorocinnmaoyl chloride derived polynorbornene (PNORCNF) on the addition of 1‐pyrenemethanol (PM) as a sensing probe. A significant change in the PNORCNF/PM microenvironment's polarity was observed with increasing PM concentration keeping the solvent (THF) unaltered. The change in polarity could be well documented with the morphological changes of the PNORCNF/PM system. We proposed π‐π interaction between PM and cinnamoyl moiety of PNORCNF for this type of well‐controlled hierarchical self‐aggregation.

The flavone apigenin (APG), alone as well as in combination with other chemotherapeutic agents, is known to exhibit potential anticancer effects in various tumors and inhibit growth and metastasis of melanoma. However, the potential of apigenin nanoparticles (APG-NPs) to prevent lung colonization of malignant melanoma has not been well investigated. APG-loaded PLGA-NPs were surface-functionalized with meso-2,3-dimercaptosuccinic acid (DMSA) for the treatment of melanoma lung metastasis. DMSA-conjugated APG-loaded NPs (DMSA-APG-NPs) administered by an oral route exhibited sustained APG release and showed considerable enhancement of plasma half-life, Cmaxvalue, and bioavailability compared to APG-NPs both in plasma and the lungs. DMSA-conjugated APG-NPs showed comparably higher cellular internalization in B16F10 and A549 cell lines compared to that of plain NPs. Increased cytotoxicity was observed for DMSA-APG-NPs compared to APG-NPs in A549 cells. This difference between the two formulations was lower in B16F10 cells. Significant depolarization of mitochondrial transmembrane potential and an enhanced level of caspase activity were observed in B16F10 cells treated with DMSA-APG-NPs compared to APG-NPs as well. Western blot analysis of various proteins was performed to understand the mechanism of apoptosis as well as prevention of melanoma cell migration and invasion. DMSA conjugation substantially increased accumulation of DMSA-APG-NPs given by an intravenous route in the lungs compared to APG-NPs at 6 and 8 h. This was also corroborated by scintigraphic imaging studies with radiolabeled formulations administered by an intravenous route. Conjugation also allowed comparatively higher penetration as evident from an in vitrothree-dimensional tumor spheroid model study. Finally, the potential therapeutic efficacy of the formulation was established in experimental B16F10 lung metastases, which suggested an improved bioavailability with enhanced antitumor and antimetastasis efficacy of DMSA-conjugated APG-NPs following oral administration.

The rapid and reliable detection of triethylamine (TEA), a toxic, explosive, volatile organic compound at room temperature, is highly significant for food safety, environmental, and human health monitoring. This manuscript reports a layered molybdenum disulfide (MoS2) nanosheet-coated polypyrrole (PPy) nanorod-based heterostructure sensor (MsPy) which offers superior sensing properties toward TEA at room temperature (25 °C). Herein, different MsPy nanocomposites were synthesized, followed by a controlled sulfidation reaction through dissolution, diffusion, and regrowth mechanisms. Optimizing the ratio of the precursor of molybdenum trioxide (MoO3/PPy) is crucial for achieving effective deposition of a layered MoS2nanosheet on the PPy surface. The as-prepared MoS2nanosheet-coated PPy sensor (MsPy_40) enables one to selectively detect trace TEA vapor at 25 °C with a detection lower limit of 0.5 ppm. The MsPy_40 sensor exhibits 17 times higher response than the pristine MoS2nanosheet to 50 ppm TEA, with rapid response (∼3.9 s) and recovery (∼19.6 s), along with better stability, good selectivity, and remarkable repeatability. The significantly enhanced sensing performance is attributed to the unique surface morphology of the layered MoS2nanosheet-coated PPy nanorod and the formation of a p–n heterojunction between PPy and MoS2.

Nanotechnology has acquired an immense recognition in cancer theranostics. Considerable progress has been made in the development of targeted drug delivery system for potent delivery of anticancer drugs to tumor-specific sites. Recently, multifunctional nanomaterials have been explored and used as nanovehicles to carry drug molecules with enhanced therapeutic efficacy. In this present work, graphene oxide quantum dot (GOQD) was conjugated with folic acid functionalized chitosan (FA-CH) to develop a nanocargo (FA-CH-GOQD) for drug delivery in cancer therapy. The synthesized nanomaterials were characterized using Fourier transform infrared spectroscopy, ultraviolet–visible spectroscopy, scanning electron microscopy, transmission electron microscopy, and dynamic light scattering. Photoluminescence spectroscopy was also employed to characterize the formation of GOQD. To validate the efficacy of FA-CH-GOQD as nanocarriers, doxorubicin (DOX) drug was chosen for encapsulation. The in vitro release pattern of DOX was examined in various pH ranges. The drug release rate in a tumor cell microenvironment at pH 5.5 was found higher than that under a physiological range of pH 6.5 and 7.4. An MTT assay was performed to understand the cytotoxic behavior of GOQD and FA-CH-GOQD/DOX. Cytomorphological micrographs of the A549 cell exhibited the various morphological arrangements subject to apoptosis of the cell. Cellular uptake studies manifested that FA-CH-GOQD could specifically transport DOX within a cancerous cell. Further anticancer efficacy of this nanomaterial was corroborated in a breast cancer cell line and demonstrated through 4′,6-diamidino-2-phenylindole dihydrochloride staining micrographs.

Polymers have a major role in the controlled delivery of pharmaceutical compounds to a targeted portion of the body. In this quest, a high priority research area is the targeted delivery of ophthalmic drugs to the interior regions of the eyes. Due to their complex anatomical/biochemical nature. This necessitates an advanced drug delivery cargo that could administer a therapeutic agent to the targeted location by evading various obstacles. The ongoing focus is to design an ophthalmic formulation by coupling it with a smart in situforming polymeric hydrogel. These smart macromolecules have an array of unique theranostic properties and can utilize the in vivobiological parameters as a stimulus to change their macromolecular state from liquid to gel. The fast gelling hydrogel improves the corneal contact time, facilitates sustained drug release, resists the burst-out effect, and assists drug permeability to anterior regions. This review summarizes the rationale, scientific objectives, properties, and classification of the biologically important in situhydrogels in the niche of ophthalmic drug delivery. The current trends and prospectives of the array of stimulus-responsive polymers, copolymers, and nanomaterials are discussed broadly. The crucial biointerfacial attributes with pros and cons are reviewed by investigating the effect of the nature of polymers as well as the ratio/percentage of additives and copolymers that influence the overall performance.

The fabrication of an effective in situ gelling ophthalmic drug delivery vehicle is recently received enormous interest to overcome the demerits of conventional ocular solutions and achieve desired therapeutic efficacy. Poloxamer 407 and poloxamer 188 are among the most commonly used poloxamers in ocular drug delivery due to thermoreversible gelation property, high solubility in water and transparent gel formation capacity which does not hamper normal vision. In this review, we have mostly focused on the thermogelation properties of poloxamer 407 as well as various methods to evaluate the poloxamer based ophthalmic in situ gel for their potential applications in ocular drug delivery and have also discussed about different strategies to improve thermogelation properties and drug release behavior of poloxamer 407 based ophthalmic formulations. We have also discussed here that the use of poloxamer 407 as thermoreversible in situ gel in colloidal drug carrier systems has proved to be an effective strategy for increasing penetration of drugs, enhancing therapeutic action, and reducing drug release rate.

Triple negative breast cancer (TNBC), characterized by its aggressive and highly metastatic nature, is difficult to cure by the currently available therapies. In our investigation, folic-acid-adorned PEGylated graphene oxide (FA-PEG-GO) was synthesized by modifying graphene oxide (GO) with folic acid-PEG conjugate (FA-PEG-NH2) by EDC/NHS coupling reaction. FA-PEG-GO exhibited an exceptional potential to attenuate cell migration of TNBC cell line ,MDAMB-231 as compared to GO because of the adorned folic acid moiety, which rendered better targeting. FA-PEG-GO inhibited cell migration by actin depolymerization and perturbing lamellipodia formation. The immunocytochemistry and western blot data unraveled the fact that FA-PEG-GO inhibited cell migration by targeting miR-21 by restricting the nuclear translocation of NFκB. The downregulation of miR-21 resulted in the elevation of PTEN expression which sequentially downregulated pFAK resulting in inhibition of cell migration. Moreover, upregulation of PTEN in FA-PEG-GO treated cells led to the decrease in expression of the downstream regulators including pAkt(Ser473) and pERK1/2, which contributed to the retardation of cell migration. Interestingly, the overexpression of NFκB-p65 by the transfection of NFκB-p65 expression plasmid in TNBC cells reversed the inhibitory effect of FA-PEG-GO on the nuclear translocation of NFκB-p65 which stabilized miR-21 expression and successively downregulated PTEN expression in FA-PEG-GO treated cells. Furthermore, miR-21 overexpression by transfection of miR-21 mimic in turn downregulated PTEN expression and sequentially restored the expression of pFAK even upon FA-PEG-GO treatment. miR-21 overexpression also compensated the inhibitory effect of FA-PEG-GO on pAkt(Ser473) and pERK1/2 which was evident from their significant expression in FA-PEG-GO-treated cells. The studies on chick embryo model ratified the ex ovoantimigratory efficacy of FA-PEG-GO. Altogether, our study unveiled the enormous potential of FA-PEG-GO to attenuate migration of TNBC cell line, MDAMB-231 by targeting the miR-21/PTEN axis through NFκB and thereby providing insights on cancer treatment.

Inorganic lead halide perovskite nanocrystals have now become an emerging material for modern nanodevice applications. But, the huge toxicity of lead to the ecosystem has limited its applications in modern technology. In this view, a large organic cation-based metal halide perovskite may be considered the most efficient supercapacitor electrode material. Here, a new type and high molecular organic cations based low-dimensional metal halide perovskite (LDMHP) nanocrystals (NCs) are synthesized by a chemical process and their performances as supercapacitor electrode is tested. An excellent charge storage capacity and especially the Tin (Sn)-based perovskite NCs showed a very high specific capacitance and energy density of ~1536 Fg−1and ~213 Whkg−1at a current density of 2.0 Ag−1, respectively. The calculated variable parameter (b) value from cyclic voltammetry showed that the total capacity of the Sn-based perovskite NCs electrode is controlled by capacitor-like behaviour. The Sn NCs also found to have a very high DC dielectric constant at room temperature, possibly responsible for their superior supercapacitor performance. A solid-state supercapacitor based on synthesized NCs was used for real-life applications of supplying sufficient power to light emitting diodes (LEDs) for a long time.

Bacteria endogenously residing within the plant tissues have attracted significant attention for production of biopolyester, polyhydroxyalkanoates (PHAs). Bacillus cereusRCL 02 (MCC 3436), a leaf endophyte of oleaginous plant Ricinus communisL. accumulates 81% poly(3-hydroxybutyrate) [P(3HB)] of its cell dry biomass when grown in mineral salts (MS) medium. The copolymer production efficiency of B. cereusRCL 02 was evaluated in valeric acid supplemented MS medium under biphasic cultivation condition. The copolymer so produced has been compared with the P(3HB) isolated from RCL 02 in terms of thermal, mechanical and chemical properties. Valeric acid supplementation as co-substrate in the medium has led to the production of copolymer of 3-hydroxybutyrate (3HB) and 3-hydroxyvalerate (3HV) [P(3HB-co-3HV)] with 14.6 mol% 3HV. The identity of the polymers has been confirmed by X-ray diffraction (XRD) analysis, Fourier transform infrared (FTIR) and nuclear magnetic resonance (NMR) spectroscopic studies. Thermogravimetric analysis (TGA) revealed that P(3HB) and P(3HB-co-3HV) films degraded at 278.66°C and 273.49°C, respectively. The P(3HB-co-3HV) showed lower melting temperature (165.03°C) compared to P (3HB) (170.74°C) according to differential scanning calorimetry (DSC). Incorporation of 3HV monomers decreased the tensile strength (21.52 MPa), tensile modulus (0.93 GPa), storage modulus (E′) (0.99 GPa) and increased % elongation at break (12.2%) of the copolyester. However, P(3HB) showed better barrier properties with lower water vapor transmission rate (WVTR) of 0.55 g-mil/100 in2/24 h. These findings emphasized exploration of endophytic bacterial strain (RCL 02) to produce biodegradable polyesters which might have significant potential for industrial application.

This work develops a rationale for effective sensitization of trivalent lanthanide cation (Ln3+) luminescence in a semiconductor nanoparticle by examining the luminescence characteristics of Ln3+dopants in titanium dioxide nanoparticles [Ti(Ln)O2] [Ln = praseodymium (Pr), neodymium (Nd), samarium (Sm), europium (Eu), gadolinium (Gd), terbium (Tb), dysprosium (Dy), holmium (Ho), erbium (Er), thulium (Tm), or ytterbium (Yb)], as a representative model system. For excitation of the TiO2host at 350 nm the intraconfigurational 4f–4f sharp luminescence bands are observed for the Nd, Sm, Eu, Ho, Er, Tm, and Yb incorporated (doped) nanoparticles, and no such luminescence is observed for the Pr, Gd, Tb, and Dy containing nanoparticles. While host sensitized luminescence of lanthanide ions dominate the emission in the Nd and Sm incorporated nanoparticles, the host sensitization effect is less pronounced for the Eu and Yb containing systems, and for the Ho, Er, and Tm doped nanocrystals only a subset of the dopant ions’ luminescence bands is sensitized. The experimental observations of the host sensitized Ln3+luminescence properties in the [Ti(Ln)O2] nanoparticles can be rationalized by considering that the dopant ions act as charge traps in the host lattice and associated environment induced luminescence quenching effects. Using these results, an energy offset between the trap site and the nanoparticle’s band edge that will generate an optimal host sensitized dopant emission is proposed. The approach presented necessarily improves over a combinatorial approach to select the host and dopant moieties, with the benefit of providing physicochemical insight regarding the nature of photophysical processes in a given host (semiconductor nanoparticle)–guest (Ln3+) composite system.

Over the past few epochs, emerging transdermal drug delivery systems (TDDSs) have gotten major devotion through incessant level of interest. The effort of this work is to understand the influence of nano-reinforcing agent on the morphology, property and its drug carrying capacity of the nanohybrid reinforced ketorolac tromethamine (KT) drug loaded electrospun nanofibrous web. In this study, cellulose nanocrystals (CNCs) extracted successfully from jute fibres (JF) and nanocollagen (NCG) was isolated from waste fish scales for the assembling of CNC-NCG reinforced MC/PVA/PEG electrospun nanofibrous bio-nanocomposites (BNCs) mat for transdermal drug delivery applications. The isolated nanoparticles (CNC & NCG) and the synthesized electrospun bio-nanocomposite were characterized by Fourier transform infrared (FTIR) spectroscopy, X-ray diffraction (XRD), Scanning electron microscopy (SEM), optical microscopy, Field emission scanning electron microscopy (FESEM).

Diosgenin (DGN) is a natural bioactive steroidal saponin from therapeutic herbs and it exhibits potential anticancer efficacy. Here, we report the preparation of poly lactide-co-glycolide (PLGA)-encapsulated diosgenin nanoparticles (PLGA-DGN NPs) and characterization of their physicochemical nature, and morphology as well as inspect their drug-loading capability, in vitrodrug release, pharmacokinetics, bio-distribution, safety profile. The in vitroand in vivoantineoplastic activities of PLGA-DGN NPs were also examined against the MCF-7 breast cancer cell line and in the Ehrlich ascites carcinoma (EAC) tumor xenograft model, respectively. The results displayed an appropriate size (∼147 nm), spherical shape, and a narrow polydispersity index. The nanoparticles showed a high encapsulation efficacy (78%), loading capacity (8%), good colloidal stability, and an initial burst release at an acidic medium. The nanoparticles exhibited significant cytotoxic activity at their IC50dose compared to diosgenin. PLGA-DGN NPs facilitated cellular internalization of DGN in human breast cancer MCF-7 cells and extended the blood circulation time showing an excellent pharmacokinetic profile. Bio-distribution study revealed that PLGA-DGN NPs could significantly enhance DGN accumulation in tumor tissue. The safety profile of the PLGA-DGN NPs was confirmed in histopathologic, hematologic, and immunologic parameters of Swiss albino mice. At the same time, an effective antiangiogenic, and antiproliferative potential of PLGA-DGN NPs were exhibited in mice tumor xenograft model by showing tumor regression and down-regulating CD31 and Ki-67 expression. Therefore, PLGA-DGN NPs could be utilized as a promising anticancer drug, opening up a new avenue for further research.

The incidence of hepatocellular carcinoma (HCC) is rising dramatically in Europe, driven by the increasing prevalence of cirrhosis associated with hepatitis C virus (HCV) infection and both alcoholic and nonalcoholic fatty liver diseases (ALD and NAFLD, respectively). At the 2011 "Women in Hepatology" meeting in Modena, Italy, aspects of this subject were discussed, including the roles of hypoxia and serpins in progressive chronic liver disease and carcinogenesis, but with a particular focus on the advances of serum-based tools and their application to novel biomarker detection. Both proteomic and metabolomic technologies were appraised in the context of biomarker signatures identifying either cirrhosis and risk of cirrhosis or HCC in high-risk groups of patients. While HCC complicating chronic liver disease occurs less frequently in women as compared to men, the relative protection afforded to the female sex is lost after menopause. In postmenopausal women, HCC incidence increases and tends to follow a more aggressive course. This aspect will be covered here and will be the basis of future collaborative studies for "Women in Hepatology." [ABSTRACT FROM AUTHOR]

Hydroxypropylcellulose (HPC) has been used as a steric stabilizer for preparing polyaniline dispersions using the route of oxidative dispersion polymerization of aniline. Using strongly acidic conditions (1 mol 4;l−1 HCl), low temperature of about 2 °C and a concentration of aniline as low as 0.5%, ammonium peroxodisulfate at 1.25% and hydroxypropylcellulose concentrations at 0.5–1 g d l−1, unstable dispersions were obtained not only in water but also in aqueous alcohols (ethanol and methanol) up to at least 70 vol% alcohol. In contrast, dispersions that remained stable for at least 72 h were obtained when the alcohol concentration of the medium was as high as about 80 vol%. Kinetic studies of the polymerization systems suggested that success in the latter case was due to a lowering of the rate of polymerization. Transmission electron microscopy studies showed that dispersion particles prepared in 80 vol% alcohol media are spherical in shape and their diameter decreases with increasing stabilizer concentration. However, a change of morphology from spherical to aggregated needle‐shaped was observed when the rate was increased by increasing the aniline concentration from 0.5% to 0.75% g d l−1 in the above recipe. The aggregated particles were found to be broken down to spherical nanoparticles when the as‐prepared dispersions were sonicated for about 30 min. The sonicated dispersion on drying showed the presence of fractal clusters of polyaniline particles in the dried film. The fractal dimension was determined to be 1.77 which agreed well with the theoretical value determined by computer simulation based on a diffusion limited cluster–cluster aggregation model in three dimensions.© 2001 Society of Chemical Industry

Disposed battery is a huge source of graphite in our environment. This graphite can be recycled by carrying out electrolysis at fixed voltage and the obtained product can be easily converted into graphene by the generation of graphene oxide (GO) as an intermediate using Hummer’s method. GO is converted into chemically reduced graphite oxide (CRGO) by sodium carbonate treatment and the material obtained is used as a filler in a drug (Ketorolac Tromethamine) loaded Hydroxypropyl methylcellulose (MC) matrix. The KT loaded CRGO\MC nanocomposite films is used to develop transdermal film for drug delivery where CRGO acts as a carrier. The recycled graphite (RGF), GO and CRGO materials has been characterized by Fourier Transform Infrared (FTIR) spectroscopy, X-ray Diffraction (XRD), Ultra-violet (UV) spectroscopy, Transmission Electron Microscopy (TEM), Thermo-Gravimetric Analysis (TGA) and Dynamic Light Scattering (DLS). KT loaded CRGO\MC nanocomposite films are characterized by TGA, XRD and moisture absorption properties analysis. The experimental result reveals the formation of successful exfoliated and stable KT loaded CRGO\MC transdermal film. XRD study reveals the crystalline nature of nanocomposite films. In vitrodrug release studies showed that CRGO\MC based films can be used for controlled transdermal drug delivery applications.

Graphene, a Dirac material, permits the free flow of electrons on its surface. The interface of graphene with different bio-materials is the emerging interest. In this paper, we describe interfaces of graphene variants and two photosynthetic species (belonging to the class of alpha-proteobacteria), Rhodobacter spand Rhodopseudomonas sp, both using photon capture in their respective electron transport process. When grown on graphene oxide (or its exfoliated forms obtained after microwave treatment) the bacterial species show differential pigment excretion patterns, which is a measure of their photon driven electron-transport-chain activity. The responses are measured by hydrodynamic diameters of pigment clusters and steady-state quantum yield and time-dependent fluorescent emission patterns. The responses carry fingerprints of graphene-specific effects on the respective microbes. Interestingly, there is a reciprocal relationship between the size of the pigment cluster formed in the presence of graphene (which varies for the two microbes) and the rate of fluorescence emission change. The report opens up the possibility of developing photo-sensing and light-harvesting devices exploiting the richness and diversity of this interface of the free-flowing electrons of this 2D-material (graphene) and these cells, undergoing graphene-specific dynamics of pigmentation.

This study reports application of electrospinning for controlled drug delivery by using polyurethane monolithic nanofibrous web. The endeavor of this study was to explore the effects on release, antimicrobial activity, and morphological behavior of drug–nanoclay intercalates vis-à-vis direct drug inclusion in the form of nanofibrous structures. Antibiotic drug, tetracycline hydrochloride was incorporated into montmorillonite clay interlayer spacing and then embedded into the synthetic polymeric nanofibrous structures. In vitro release study was conducted to assess the release characteristics. Disk diffusion experiment was organized to observe antimicrobial activities and finally human dermal fibroblast cells were grown on the nanofibrous web to address morphological behavior. The results showed that the nanoclay performed as a better way in the form of sustained drug release carrier. The produced electrospun nanofibrous webs could provide broad spectrum antibacterial activities beneficial for topical applications. The fibroblast cell growth on the nanofibrous web caused proliferation to result a mesh like structure which would certainly have a positive effect on wound healing.

Nanostructured conducting polymer provides higher surface area for analyte vapor sensing. This investigation aims to synthesize rod-like polypyrrole (PPY) silver nanocomposite tailored by sodium cholate surfactant as soft template for sensing of acetone vapor. During oxidative polymerization of pyrrole by ferric chloride Ag nanoparticle gets deposited on PPY by simultaneous reduction of silver nitrate. The crystal structure, surface morphology and nature of interfacial interactions between the two components of the prepared PPY-silver nanocomposite (PPY-Ag) are analyzed by standard characterization techniques. The Ag nanoparticles deposition on rod-like PPY increases with increasing silver nitrate concentration up to an optimum level. The PPY-Ag nanocomposites show chemiresistive type dynamic sensing responses toward methanol, ethanol and acetone vapor in a mixture with air. A comparative evaluation of typical vapor sensing parameters (% response, response time, recovery time, reproducibility, and selectivity) of PPY-Ag nanocomposite sensor obtained for different volatile organic compounds with those of the pristine PPY sensor is reported. Interestingly, the rod-like PPY-Ag nanocomposite is found to selectively sense acetone vapor showing better % response than that of the other analytes, viz., methanol, ethanol, propanol, water vapor and formaldehyde. The differences in their responses for the different analytes and the selectivity toward acetone vapor are established by considering the difference in their interactions with the nanocomposite.

A simple and green chemistry approach for the preparation of reduced graphene oxide nanosheets was successfully demonstrated through the reduction of graphene oxide (GO) to obtain greenly-reduced graphene oxide (GRGO) using various green reagents. Without using toxic and harmful chemicals, this method is environmentally-friendly and suitable for the large-scale production of graphene. The prepared GO and GRGO were characterized by UV–Visible, X-ray diffraction, and Fourier transform infra-red spectroscopic analysis which showed a clear indication of the removal of oxygen-containing groups from the GO and the formation of GRGO. The morphology of the GRGO samples was characterized by transmission electron microscopy. Dynamic light scattering was used to measure the size of the GRGO particles along with zeta potential measurements. Electrical conductivity measurement was used to check the extent of reduction of GO to GRGO samples. The electrochemical properties of these carbonaceous materials were determined by cyclic voltammetry. The methods employed can lead to the preparation of GRGO can be effectively used in sensors and various electronic device fabrications.