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A novel and cost-effective 2,4-dinitrophenyl hydrazine derived from Schiff base 1-benzylidine-2-(2,4-dinitrophenyl) hydrazine (L) was designed and characterized using various spectroscopic techniques. The interaction between L and bovine serum albumin (BSA) has been carried out using UV–Vis and fluorescence spectroscopy, DSC, SEM, and molecular docking methods. The phosphate buffer (pH = 7. 4) solution of BSA showed fluorescence emission maxima at 342 nm. Upon addition of L to the BSA solution, it quenched the fluorescence emission at 342 nm. The quenching of the fluorescence emission is due to the formation of a complex between L and BSA. The binding constant was calculated from the fluorescence titrations and found to be 6. 7 4 5 × 1 0 6 M − 1 . Further, molecular docking analysis was carried out to establish the binding between L and BSA. [ABSTRACT FROM AUTHOR]

The synthesis of gold nanoparticles reinforced functionalized single‐walled/multi‐walled carbon nanotubes nanohybrid based polyaniline nanocomposites were carried out using in situ polymerization. The chemical interaction and nanostructured morphology of the synthesized nanocomposites are studied using ultraviolet–visible spectroscopy, Fourier transform infrared spectroscopy, Raman spectroscopy, x‐ray diffraction analysis, x‐ray photoelectron spectroscopy, and field emission scanning electron microscopy. Thermal stability of synthesized PANI/Au@f‐SWNTs is boosted by a magnitude of 30°C as compared with the pristine PANI matrix, which is attributed to a strong barrier effect because of the development of tortuous path that resulted from a uniform distribution of Au@f‐CNTs throughout the PANI matrix. For PANI/Au@f‐SWNTs, the AC conductivity and dielectric permittivity are improved by a value of 83.58 S/cm and 1.35 × 10−5 as well as the dielectric loss is reduced by a factor of 0.11 in comparison with the pure PANI matrix at an applied frequency of 106 Hz. PANI/Au@f‐SWNTs and PANI/Au@f‐MWNTs ternary nanocomposites exhibited excellent selectivity toward the hazardous Cr(VI) heavy metal ions in an aqueous medium with a limit of detection of 0.74 and 0.89 μM with a binding constant of 1.028 × 105 and 3.46 × 104 M−1, respectively, that can be selective and sensitive for the detection of Cr(VI) metal ions in water at trace level. [ABSTRACT FROM AUTHOR]

The recent research paper describes the synthesis of the silver nanoparticles (AgNPs) coated functionalized single-walled carbon nanotubes (f-SWNTs) hybrid nanofillers reinforced polyaniline (PANI) (PANI/Ag@f-SWNTs) nanocomposites, which was carried out through in situ polymerization process to analyze its thermal, dielectric, and sensing properties. The Fourier transform infrared (FTIR) spectroscopy showed the occurrence of interphase interactions within the Ag@f-SWNTs hybrid nanofillers and PANI matrix. The Raman spectroscopy indicated the blue shift with increase in intensity of the band that confirms the decoration of AgNPs on the surface of the f-SWNTs. The structural behavior of the PANI/Ag@f-SWNTs nanocomposites was investigated via X-ray diffraction (XRD) spectroscopy, which revealed the presence of the face centered cubic (FCC) crystal structure of the AgNPs. X-ray photoelectron spectroscopy (XPS) evaluated the chemical composition and bond structure of the nanocomposites. The morphology of the nanocomposites is studied from scanning electron microscopy (SEM) and transmission electron microscopy (TEM), which displayed the well decoration of the AgNPs on the surface of the f-SWNTs. The thermal and dielectric properties of the PANI/Ag@f-SWNTs nanocomposites were examined by using thermogravimetry-differential scanning calorimetry (TG-DSC) and dielectric relaxation spectroscopy (DRS), respectively. The thermal and dielectric properties of the PANI/Ag@f-SWNTs nanocomposites were significantly enhanced owing to the development of robust interphase interactions between the Ag@f-SWNTs hybrid nanofillers and PANI matrix that arises due to the homogeneous dispersion of the Ag@f-SWNTs nanohybrids within the PANI matrix through in situ polymerization process. The Cr(VI) metal ion sensing behavior of the PANI and PANI ternary nanocomposites was studied through UV-Vis spectroscopy, which indicates significant improvement in sensing behavior of the PANI/Ag@f-SWNTs ternary nanocomposites as compared to the pure PANI matrix. [ABSTRACT FROM AUTHOR]

An efficient and eco-friendly approach is adopted for the synthesis of highly stable L-alanine assisted nano gold based polyvinyl alcohol nanocomposite hybrid films (Au/PVA).The-COOH groups of L-alanine and oxygeneous groups of polyvinyl alcohol are utilized for the synthesis of size controlled gold nanoparticles. The as-synthesized nanocomposites show rapid and selective detection of Cu2+ ion in aqueous medium. With addition Cu2+ ion to as-synthesized nanocomposites, the SPR peaks of Au NPs (538 nm) decrease with occurrence of a red shift as well as a new peak is observed at higher wavelength which is due to the aggregation of gold nanoparticles in the nanocomposites hybrid films. Scanning electron microscope (SEM) micrograph and energy dispersive spectroscopy (EDS) reveal the aggregation of gold nanoparticles in the nanocomposite hybrid films. The limit of detection and limit of quantification for Cu2+ ion are 40 nM and 133 nM respectively. This technique for detection of Cu2+ ion in waste water samples is inexpensive and eco-friendly since no any toxic chemicals are used. In the presence of Cu2+ ion, the colour of the hybrid film is changed hence, this method also involves visual detection of Cu2+ ion without use of electrolyte or transducer. Further, many reported methods represent the in situ monitoring of Cu2+ ion, but the present hybrid film can be used for in situ as well as ex situ monitoring of Cu2+ ion. [ABSTRACT FROM AUTHOR]

Silver nanoparticles embedded reduced graphene oxide (rGO−Ag) nanocomposites are synthesized by green technique using clove leaf aqueous extract as reducing agent. The surface plasmon resonance (SPR) peak of silver nanoparticles (Ag NPs) at 410 nm in rGO−Ag nanocomposites is analysed by UV–visible spectroscopy. The intensity of surface plasmon resonance (SPR) peak of Ag NPs in rGO−Ag nanocomposites is decreased with addition of Hg2+ ion at small interval of time. This is due to the occurrence of redox reaction between Ag(0) and Hg2+ and also for the formation Ag/Hg amalgam. The lower limit of detection (LOD) of rGO−Ag nanocomposites for Hg2+ ion is found to be 9.5 nM. Moreover, the rGO−Ag nanocomposites may be used as catalyst for degradation of methylene blue (MB) by sodium borohydride (NaBH4) at ambient temperature. The adsorption efficiency of methylene blue is increased due to hydrogen bonding and electrostatic interaction along with π–π stacking between the catalyst and the dye molecules. The methylene blue is degraded within a small time due to large surface area and more number of active sites of rGO−Ag nanocomposites. The as‐synthesized nanocomposite is a potential hybrid material having dual activity as Hg2+ sensing and catalytic behaviour in degradation of methylene blue. Herein, clove leaves extract is used for the reduction of Ag+ to Ag(0) and also for the reduction of GO to rGO. The as‐synthesized rGO−Ag nanocomposites show dual activities as sensor for Hg2+ ion with high sensitivity and catalyst in degradation of methylene blue. [ABSTRACT FROM AUTHOR]

Nanoclay reinforced starch‐co‐PAA hybrid nanocomposite thin films are synthesized by in situ polymerization technique in aqueous solution. The interactions of clay with starch‐co‐PAA are studied by Fourier transform infrared spectroscopy (FTIR) and X‐ray diffraction (XRD). The morphology of nanoclay platelets in starch‐co‐PAA hybrid nanocomposite thin film is studied by scanning electron microscope (SEM) and high‐resolution transmission electron microscope (HRTEM) images are used to investigate micro and nanostructural behavior of clay platelets in starch‐co‐PAA matrix. It is noticed that, the thin film has an exfoliated structure at 3 wt% clay loading whereas; clay platelets are agglomerated in higher percentage of clay. The synthesized materials have chemical resistance of 22% more than the virgin matrix. The biodegradable properties of the nanocomposite thin films are reduced by 20% due to incorporation of nanoclay. The oxygen barrier property of starch‐co‐PAA/clay thin film is reduced by seven folds as compared to starch‐co‐PAA. From the measurement of refractive indexes, it is found that, the transparency of the nanocomposite thin films are reduced by around 10% by reinforcement of nanoclay. The results show a substantial enhancement in oxygen barrier property and reduction of refractive index on clay loading, which may permit the synthesized materials suitable for packaging applications. POLYM. COMPOS., 40:229–239, 2019. © 2017 Society of Plastics Engineers [ABSTRACT FROM AUTHOR]

In present work, Dextran‐grafted poly(acrylic acid) [D‐g‐PAA] hybrid nanocomposites are prepared in aqueous medium with reinforcement of various concentrations of nano‐CaCO3 (CC) through in situ polymerization of acrylic acid. The chemical interactions between filler and polymeric matrix are studied by Fourier transform infrared spectroscopy. The structural properties of the D‐g‐PAA/CC nanocomposite are investigated by X‐ray diffraction, field‐emission scanning electron microscopy, and high‐resolution transmission electron microscopy. The aloe vera plant structured morphology is noticed by interaction of dextran with PAA, where CC nanoparticles are embedded within the D‐g‐PAA matrix. The thermal stability of the D‐g‐PAA/CC hybrid nanocomposites is enhanced by the incorporation of nano‐CC. The tensile properties and antibacterial behavior of D‐g‐PAA/CC hybrid nanocomposites are also increased by incorporation of nano‐CC. The oxygen barrier behavior of hybrid nanocomposites is increased by 11‐folds with a reinforcement of 8 wt % of nano‐CC. Herein, the incorporation of nano‐CC enhances the oxygen barrier, thermal, and antimicrobial properties of the D‐g‐PAA matrix by which the synthesized material is suitable for packaging applications. © 2019 Wiley Periodicals, Inc. J. Appl. Polym. Sci. 2020, 137, 48298. [ABSTRACT FROM AUTHOR]

In situ synthesized graphene quantum dots (GQDs) decorated with green synthesized AgNPs (AgNPs@GQDs) hybrid nanofillers reinforced polyaniline (PANI) ternary nanocomposites was synthesized by in situ polymerization. The UV-Vis spectroscopy showed the presence of AgNPs at 402 nm in AgNPs@GQDs hybrid nanofillers, and a charge transfer complex was formed between PANI matrix and AgNPs@GQDs hybrid nanofillers. The direct optical band gap of the ternary nanocomposites calculated from UV-Vis analysis is found to be 3.085 eV, which indicates the ternary nanocomposite may be used for solar cell applications. The Fourier transfer infrared (FTIR) spectroscopy represented the occurrence of interphase interactions between the ternary nanocomposites. The X-ray diffraction (XRD) data showed the positions and intensities of the hybrid nanofillers and PANI matrix. The morphology of the ternary nanocomposites was confirmed by scanning electron microscopy (SEM). The thermogravimetric analysis (TGA) attributed to the thermal degradation of the ternary nanocomposites. The cyclic voltammetry (CV) showed the oxygen reduction potential of the ternary nanocomposites. Photoluminescence (PL) activity of the ternary nanocomposites was confirmed by fluorescence spectroscopy. The AC conductivity of the ternary nanocomposites significantly increases as compared to pure PANI due to the presence of uniformly distributed hybrid nanofillers within PANI matrix. [ABSTRACT FROM AUTHOR]

A novel chromone-based Schiff base L was designed and synthesized by condensing an equimolar amount of 3-formyl chromone and 2,4-dinitro phenyl hydrazine. Schiff base L was developed as a potent colorimetric and fluorescent molecular probe to recognize Hg2+ ions over other competitive metal ions. In the presence of Hg2+, Schiff base L displays a naked-eye detectable color change under day and UV365 nm light. Various UV-Vis and fluorescence studies of L were performed in the absence and presence of Hg2+ to determine the sensitivity and the sensing mechanism. With high selectivity and specificity, the detection limit and association constant of L for Hg2+ were estimated at 1.87 µM and 1.234 × 107 M−1, respectively. The developed sensor L was applied to real soil samples for the detection of Hg2+. [ABSTRACT FROM AUTHOR]

Bovine serum albumin (BSA)-based biomaterials have garnered significant attention for their remarkable potential in wound healing, primarily due to their effective biological actions in addressing the skin inflammation phase and mitigating hypoalbuminemia. Motivated by these attributes, a nanocomposite hydrogel is developed by blending BSA with poly(vinyl alcohol) (PVA), complemented by the incorporation of graphene quantum dot (GQD). The FTIR study establishes a hydrogen-bonding interaction between the -NH 2 groups of BSA and the -OH group of PVA. Microscopic investigations establish that the dispersion of GQDs with an average size of 22.5 nm results in smoothening of the surface of the nanocomposite. The nanocomposite hydrogel reveals excellent swelling attributes of about 920% in a period of 6 h due to its optimum cross-linking condition. Furthermore, the hydrogel exhibits a water vapor transmission rate of 8.45 mg cm -2 h -1 , akin to the transmission rate of wounded skin. The PVA/BSA@GQD nanocomposite's antibacterial efficacy is evaluated against Morganella morganii bacteria, showing 99% killing, while its cytotoxicity assay against HeLa cells exhibited a minimum cell viability of 76% at a 20 μM concentration, which is ideal for a wound dressing material. In vivo wound healing investigations are conducted on Drosophila, showcasing a 100% wound surface closure within 4 h. This outcome is further substantiated through in vivo studies involving mice, where complete re-epithelialization is achieved within a span of 13 days. The combined results establish the PVA/BSA@GQD nanocomposite as a potential wound dressing material.