The present study deals with the green approach for the biosynthesis of copper oxide-Aloe vera (CuO-A) based nanoparticles using leaf extract of Aloe barbadensis miller. Synthesized nanoparticles were characterized through different techniques like TEM and FTIR. As the size decreases and surface area increases, these are prominently used as a very good adsorbent. The effects of different parameters like adsorbent dosage, pH, contact time, initial dye concentration and temperature are optimised to get the maximum removal of methylene blue dye from the solution. The maximum dye removal was found to be 98.89% with initial concentration of 100 mg/L at alkaline pH in 210 min., with shaking speed of 150 rpm. The Langmuir result reveals a better consistency than the Freundlich model with 95.5 mg/g. Lagergren’s model was used to study the kinetics of the system. Mechanistic behaviour was study through intra-particle diffusion study and Boyd plot. Thermodynamic study showed spontaneous and endothermic nature of the adsorption. Furthermore, synthesized CuO-A nanoparticles showed good antibacterial activity against different strains of bacteria. The zone of inhibition was found to be 11 mm, 12 mm, 8 mm and 9 mm in Pseudomonas, Klebsiella, Staphylococcus and E.coli, respectively.

中文翻译：

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生物合成氧化铜纳米粒子去除亚甲基蓝染料的动力学和热力学研究及其抗菌活性。

本研究涉及使用芦荟叶提取物生物合成氧化铜-芦荟(CuO-A)纳米颗粒的绿色方法。通过 TEM 和 FTIR 等不同技术对合成纳米颗粒进行表征。随着尺寸减小和表面积增加，它们被广泛用作非常好的吸附剂。对吸附剂用量、pH、接触时间、初始染料浓度和温度等不同参数的影响进行优化，以最大限度地去除溶液中的亚甲基蓝染料。初始浓度为 100 mg/L，碱性 pH 条件下，振荡速度为 150 rpm，210 分钟内最大染料去除率为 98.89%。Langmuir 结果显示比 Freundlich 模型具有更好的一致性（95.5 mg/g）。拉格格伦的模型用于研究系统的动力学。通过颗粒内扩散研究和博伊德图来研究机械行为。热力学研究表明吸附具有自发和吸热性质。此外，合成的CuO-A纳米粒子对不同菌株均表现出良好的抗菌活性。发现假单胞菌、克雷伯菌、葡萄球菌和大肠杆菌的抑菌圈分别为 11 mm、12 mm、8 mm 和 9 mm。