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Complete characterization and memristive study of the electrochemically active, novel Fe(ii)-polymer of a fluorescence active conjugated, hexadentate ligand.

Despite being the most common component of numerous metalloenzymes in the human body, zinc complexes are still under-rated as chemotherapeutic agents. Herein, the present study opens up a key route toward enhanced chemotherapy with the help of two ZnII complexes (ZnMBC) synthesized alongside Mannich base ligands to upsurge biological potency. Further, well-established mesoporous silica nanoparticles (MSNs) have been chosen as carriers of the titled metallodrugs in order to achieve anticancer drug delivery. A pH-sensitive additive, namely, chitosan (CTS) conjugated with biotin is tagged to MSNs for the targeted release of core agents inside tumors selectively. In general, CTS blocks ZnMBC inside the mesopores of MSNs, and biotin acts as a targeting ligand to improve tumor-specific cellular uptake. CTS–biotin surface decoration significantly enhanced the cellular uptake of ZnMBC through endocytosis. A panel of four human cancer cell lines has revealed that ZnMBC (1/2)@MSNs–CTS–biotin nanoparticles (NPs) exhibits unprecedented enhanced cytotoxicity toward cancer cells with IC50 values ranging from 6.5 to 28.8 μM through induction of apoptosis. NPs also possess great selectivity between normal and cancer cells despite this potency. Two-photon-excited in vitro imaging of normal (HEK) and cancer (HeLa) cells has been performed to confirm the biased drug delivery. Also, NP-induced apoptosis was found to be dependent on targeting DNA and ROS generation. Moreover, a lower range of LD50 values (153.6–335.5 μM) were observed upon treatment zebrafish embryos with NPs in vivo. Because of the anatomical similarity to the human heart, the heart rate of NP-treated zebrafish has been analyzed in assessing the cardiac functions, which is in favor of the early clinical trials of ZnMBC (1/2)@MSNs–CTS–biotin candidates for their further evaluation as a chemotherapeutic and chemopreventive agent toward human cancers, especially adenocarcinoma.

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The explosion in digital communication with the huge amount of data and the internet of things (IoT) led to the increasing demand for data storage technology with faster operation speed, high-density stacking, nonvolatility, and low power consumption for saving energy. Metal chalcogenide-based quantum dots (QDs) show excellent nonvolatile resistive memory behavior owing to their tunable electronic states and control in trap states by passivating the surface with different ligands. Here, we synthesized high-quality colloidal monodispersed CdSe QDs by the hot injection method. The CdSe QDs were blended with an organic polymer, poly­(4-vinylpyridine) (PVP), to fabricate an Al\CdSe-PVP\Al device. Our device shows excellent bipolar nonvolatile resistive random access memory (RRAM) switching behavior with a high current ON/OFF ratio (I ON/OFF) of 6.1 × 104, and it consumes ultralow power. The charge trapping and detrapping in the potential well formed by the CdSe QD and PVP combination result in resistive switching. This CdSe-PVP-based resistive random access memory (RRAM) device with a high I ON/OFF, ultrafast switching speed, high endurance, low operating voltage, and long retention period can be used as a high-performance and ultralow-power memristive device.

This work reports the development of carbon black‐filled flexible conductive composite as an effective electrode material to substitute of graphite for electrochemical synthesis of supercapacitive polyaniline (PAni). Elastomeric composites of acrylonitrile butadiene copolymer (NBR) as a matrix with different types of carbon black fillers viz., N660, N330 and XC72 (VULCAN® XC‐72) were prepared through melt mixing method. Among these composites, NBR‐XC72 exhibited the highest bulk electrical conductivity and charge carrier concentration coupled with good mechanical properties. Generally, high level of conductivity is required for a material to be used as an electrode in electrochemical synthesis. The NBR‐XC72 composite with 90 phr black loading can be used as an effective material for electrode electrochemical synthesis of PAni from aniline. Two different PAni samples were prepared using both graphite electrode (PAni‐G) as well as flexible composite electrode (PAni‐R). The specific capacitance of PAni‐G was found to be around 380 Fg−1 in comparison to 213 Fg−1 for PAni‐R at the discharge rate of 1 Ag−1. The retention of specific capacitance of PAni‐R was found to be 90% notably better than that of Pani‐G (81%) after 1,000 cycles of charge–discharge (CD) process. POLYM. COMPOS., 40:E1537–E1547, 2019. © 2018 Society of Plastics Engineers

No abstract

Flexible and optically transparent electrodes (TEs) are essential for most state-of-art organic optoelectronic devices (OOED). The demand for bendable electronic devices with aesthetic impact and multi-functionality has driven the rapid development of flexible TEs with improved optoelectrical and mechanical properties. However, conventional rigid TEs, that is, indium tin oxide (ITO) coated glass substrate (ITO/glass), cannot match smart devices' requirements in unique fields, like electrochromic devices, electronic skins, and wearable electronics, foldable displays, smart windows, and solar cells. To substitute extensively used ITO/glass electrodes has been endeavored because of the increasing price and inherently brittle ITO and glass substrate behavior. Emerging TEs based on the combination of the polymers substrate and conducting fillers like graphene, carbon nanotubes, metal nanowires, and transparent conducting oxides are bendable, lightweight, and inexpensive. They have shown substantial prospects to be used in the devices mentioned above. With each tiny development in these emerging TE's, such as outstanding optoelectrical and mechanical features in flexible electrodes, they become more suitable for practical applications in miscellaneous bendable devices. This review summarizes the comprehensive overview of the modern alternative flexible TEs and their implementation in bendable and stretchable devices.