The use of functional properties of native cyclodextrins in palladium nanoparticle-b-cyclodextringraphene nanosheet (Pd@CD-GNS) catalyzed carbon-carbon (C-C) coupling reactions have been investigated under green reaction conditions. The supramolecular catalyst was prepared by deposition of Pd nanoparticles (Pd NPs) on CD-GNS using ethanol as the greener solvent and in situ reducing agent. The catalyst was characterised by FTIR, XRD, RAMAN, UV-Vis spectroscopy, TEM, SAED, XPS and ICP-AES. The catalytic activity of these catalysts is investigated in C-C coupling reactions such as Suzuki-Miyaura and Heck-Mizoroki reactions of aryl bromides and aryl chlorides containing functional groups under green reaction conditions i.e. in water, under phosphine free and aerobic conditions. This catalyst afforded excellent selectivities for the products in good to excellent yields under low Pd loadings (0.2-0.05 mol%), while ensuring the recovery and reusability of the catalysts. The reused catalyst was characterized by FTIR, TEM, XPS and ICP-AES. The CD supramolecular mediators loaded on GNS act as stabilising agents for the Pd NPs. The excellent catalytic activity of this system was attributed to the presence of CDs, excellent dispersibility in water, hydrophobic nature of the GNS support for the accumulation of organic substrates in water, "Breslow effect", the presence of PTC to overcome the mass transfer limitation onto the surface of GNS and formation of ternary CD/substrate/additive complexes on the Pd-GNS surface.

In this work, for the first time, we used inherently fluorescent carbon spheres (IF‐CSP) as a doping agent to retain the electroactivity of polyaniline (PANI) in neutral media by making composite (IF‐CSP@PANI) which is an important requirement for physiological applications of PANI. To address this issue, in situ chemical oxidative polymerization of aniline is done in presence of IF‐CSP. IF‐CSP@PANI has higher electrochemical activity than PANI in cell culture media at pH 7.4 with high cycling stability which was confirmed by cyclic voltammetry (CV) and electrochemical impedance spectroscopy (EIS). In addition, this material showed great promise as a biocompatible scaffold for the adherence and proliferation of adipose derived stem cells (ADSCs) at all concentrations of IF‐CSP@PANI composite (10‐200 μg/mL) for five days of culture period and this was confirmed by MTT assay. Doping of PANI with IF‐CSP might have helped to preserve its electroactivity and cycling stability at higher pH values by hindering the deprotonation of its conducting form. Proliferation of ADSCs may be attributed to the electroactivity of the composite material. Confocal laser scanning microscopy (CLSM) images evidenced that the IF‐CSP@PANI composite was able to enter into the cytoplasm of ADSCs. These extraordinary properties might render the IF‐CSP@PANI composite as a promising candidate for bioimaging, biosensing, tissue engineering and drug or gene delivery.

The polyaniline/graphite oxide (PANI/GO) nanocomposite was prepared by the in situ chemical polymerisation method. The synthesis involved the formation of dark green coloured polyaniline/graphite oxide composite. The crystalline structure and morphology of the composite were studied using UV-visible spectroscopy (UV), X-ray diffraction (XRD) and transmission electron microscopy (TEM).The characteristic peaks in XRD and UV-visible spectra confirmed the formation of the PANI/GO nanocomposite. DC conductivity measurements were performed using a two-probe method. Dielectric responses of the composites were investigated in the frequency range100 MHz to 3 GHz by the RF impedance analyser. The dielectric constant ϵ 0 (w) and dielectric loss ϵ 00 (w) were investigated. It was observed that the dielectric constant ϵ 0 (w) and dielectric loss ϵ 00 (w) decreased with an increase in frequencies (for different wt % of GO). The antibacterial activity of this composite was examined.This is an open access article under the terms of the Creative Commons Attribution-NonCommercial License, which permits use, distribution and reproduction in any medium, provided the original work is properly cited and is not used for commercial purposes.

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