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Biological synthesis of gold nanoparticles (AuNPs) is gaining attention of researchers because of their varieties of biomedical applications. This study reported the novel, eco-friendly synthesis of AuNPs using dried fruit extract of Capsicum annum (C. annum). Biosynthesized gold nanoparticles (Ca-AuNPs) showed UV absorption peak at 540 nm and were found to be stable for up to three months. The nanoparticles were further characterized by Transmission Electron Microscopy (TEM), Fourier Transform Infrared (FT-IR), Energy Dispersive X-ray Analysis (EDAX) and X-ray diffraction (XRD) analysis. The nanoparticles were spherical in shape with size range of 20–30 nm and zeta potential study confirmed the surface charge of -26.5 mV. The Ca-AuNPs were tested for anti-angiogenic activity using Chorioallantoic membrane (CAM) assay that implied a significant anti-angiogenic efficiency of Ca-AuNPs at 100 µg/mL concentration. The antioxidant activity of Ca-AuNPs studied by 2,2- diphenyl-1-picrylhydrazyl (DPPH) assay was found to be significant with 86.0% radical scavenging activity. These nanoparticles also revealed anti-inflammatory activity at concentration range 100–1200 µg/mL with IC-50 value619.4 µg/mL. The present study includes synthesis of Ca-AuNPs by using phytoconstituents of plant material as reducing agents to efficiently exploit the biomedical applications of the nanoparticles.

The massively parallel computing capabilities of the human brain can be mimicked with the help of neuromorphic computing approach and this can be achieved by developing the electronic synaptic device. In the present work, we have synthesized gallium-doped ZnO thin films using a cost-effective hydrothermal method and characterized the thin films using field-emission scanning electron microscopy and energy-dispersive X-ray spectroscopy. Furthermore, gallium-doped ZnO memristive devices were developed using standard procedure and electrically characterized for the neuromorphic application. In particular, resistive switching and synaptic properties of gallium-doped ZnO thin films were investigated. The bipolar resistive switching with an analog memory like behavior was observed in the developed memristive devices. In the present case, good synaptic properties, endurance, and retention characteristics were observed for 0.5% Ga doped memristive device. Our results suggested that the synaptic weight, potentiation-depression, and symmetric Hebbian learning can be tuned with properly engineering the ZnO memristive device with appropriate gallium doping. The detailed analysis of I-V results suggested that resistive switching is occurred due to Ohmic and Schottky conduction mechanisms. Keywords: Memristive device, Resistive switching, Gallium doped ZnO, Electronic synapse, Potentiation and depression, Hebbian learning