Bio-Synthesis of copper nanoparticles (CuNPs) using Garlic extract to investigate antibacterial activity

Bio-synthesis of metal nanoparticles (CuNPs) is regarded as one of the recently developed, economic and environmentally benign method. In the present investigation, Copper nanoparticles were synthesized reacting garlic (Allium sativum) extract with Copper Sulphate (CuSO4∙5H2O) solution over magnetic stirrer at 80 °C for 1 hour. So-prepared CuNPs were studied by observing the color change at various time intervals.  Further, the nanoparticles were characterized using UV-Visible spectroscopy, Energy Dispersive X-ray spectroscopy (EDX) and Fourier Transform Infrared spectroscopy (FTIR). The results of UV-Vis   spectroscopy   clearly showed presence of absorption peak at 595 nm which confirmed   the   formation   of   copper nanoparticles. Likewise, the EDX spectrum depicts the presence of optical band at 8 eV which is the characteristic peak of Copper consisting of 38.747 % by weight and FTIR spectra revealed presence of various phytochemicals possessing characteristic functional groups such as carbonyl and phenolic at the surface of CuNPs. Thus, natural products available in the garlic extract help in reduction and stabilization of Copper nanoparticles.  The antibacterial activity of Copper nanoparticles was investigated against Gram +ve (Staphylococcus aureus) and Gram –ve bacteria (Escherichia coli) using Agarwell diffusion method. The results of antibacterial test showed that CuNPs were found to be much sensitive towards Gram –ve bacteria compared to gram +ve bacteria.  BIBECHANA 17 (2020) 12-18  

Bio-Synthesis of copper nanoparticles (CuNPs) using Garlic extract to investigate antibacterial activity

Bio-synthesis of metal nanoparticles (CuNPs) is regarded as one of the recently developed, economic and environmentally benign method. In the present investigation, Copper nanoparticles were synthesized reacting garlic (Allium sativum) extract with Copper Sulphate (CuSO4∙5H2O) solution over magnetic stirrer at 80 °C for 1 hour. So-prepared CuNPs were studied by observing the color change at various time intervals.  Further, the nanoparticles were characterized using UV-Visible spectroscopy, Energy Dispersive X-ray spectroscopy (EDX) and Fourier Transform Infrared spectroscopy (FTIR). The results of UV-Vis   spectroscopy   clearly showed presence of absorption peak at 595 nm which confirmed   the   formation   of   copper nanoparticles. Likewise, the EDX spectrum depicts the presence of optical band at 8 eV which is the characteristic peak of Copper consisting of 38.747 % by weight and FTIR spectra revealed presence of various phytochemicals possessing characteristic functional groups such as carbonyl and phenolic at the surface of CuNPs. Thus, natural products available in the garlic extract help in reduction and stabilization of Copper nanoparticles.  The antibacterial activity of Copper nanoparticles was investigated against Gram +ve (Staphylococcus aureus) and Gram –ve bacteria (Escherichia coli) using Agarwell diffusion method. The results of antibacterial test showed that CuNPs were found to be much sensitive towards Gram –ve bacteria compared to gram +ve bacteria.  BIBECHANA 17 (2020) 12-18  

Prunus domestica dye extraction for fabrication of zinc oxide based dye-sensitized solar cells

Aluminium doped Zinc Oxide (AZO) seed layers were deposited on Fluorine doped Tin Oxide (FTO) substrates using a spin coating technique. These were then immersed in growth solutions of zinc nitrate, hexamethylenetetramine and distilled water to develop nanoplates of Zinc Oxide (ZnO). The nanostructures of ZnO grown on FTO were studied using x-ray diffraction techniques. Dye-sensitized solar cells (DSSC) were fabricated using two prepared electrodes, one of dye-loaded zinc oxide and another that was platinum coated. The electrolyte used was potassium iodide iodine solution. The performance of the assembled DSCCs was tested by drawing an IV curve. The results showed that the short circuit current and open circuit voltages were about 10 microamperes and 270 millivolts respectively. BIBECHANA 13 (2016) 23-2

Study on the Synthesis of ZnO Nanoparticles Using <i>Azadirachta indica</i> Extracts for the Fabrication of a Gas Sensor

This paper compared the effects of A. indica plant proteins over chemical methods in the morphology of zinc oxide nanoparticles (ZnO NPs) prepared by a co-precipitation method, and ethanol sensing performance of prepared thin films deposited over a fluorene-doped tin oxide (FTO) bind glass substrate using spray pyrolysis technique. The average crystallite sizes and diameters of the grain-sized cluster ZnO NPs were 25 and (701.79 ± 176.21) nm for an undoped sample and 20 and (489.99 ± 112.96) nm for A. india dye-doped sample. The fourier transform infrared spectroscopy (FTIR) analysis confirmed the formation of the Zn–O bond at 450 cm−1, and also showed the presence of plant proteins due to A. indica dye extracts. ZnO NPs films exhibited good response (up to 51 and 72% for without and with A. indica dye-doped extracts, respectively) toward ethanol vapors with quick response-recovery characteristics at a temperature of 250 °C for undoped and 225 °C for A. indica dye-doped ZnO thin films. The interaction of A. indica dye extracts helps to decrease the operating temperature and increased the response and recovery rates of the sensor, which may be due to an increase in the specific surface area, resulting in adsorption of more oxygen and hence high response results