The green synthesis of Cerium oxide nanoparticles (CeO₂ NPs) has been carried out using Nelumbo nucifera flower extract as capping and reducing agent. Optical property is determined using Ultra Violet-Visible spectroscopy (UV-Vis). From the Fourier Transform infrared spectroscopy (FTIR), characteristic peak at 506 cm^-1 confirms the presence of Ce-O bond. The fluorite-type cubic structure is confirmed by using FT-Raman spectroscopy. The crystalline phases are identified using powder X-Ray Diffractometer (PXRD). The stability and particle size of CeO₂ NPs is interpreted using Dynamic light Scattering (DLS) analysis. The particle size, shape and surface texture is analysed using High Resolution Scanning Electron Microscope (HRSEM) and High Resolution Transmission Electron Microscope (HRTEM) techniques. Selected Area Electron Diffraction (SAED) pattern confirms the identity of crystalline phases with the P-XRD data. Elemental mapping is done by using Energy Dispersive X-ray (EDX) analysis. Thermal behaviour of the CeO₂ NPs is analysed using the Thermo Gravimetric-Differential Thermal Analyser (TG-DTA) technique. The in vitro cytotoxic effect of CeO₂ NPs is tested against HCT 116 human colon cancer cell line using MTT assay. It is recorded that, IC50 of the CeO₂ NPs was 41.60 µg/mL. 62% of cell viability is minimized at 40 µg/mL in 46 h. This result enhances the importance of using greener eco-friendly method for synthesizing CeO₂ NPs with effective anticancer activity.

中文翻译：

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Nelumbo nucifera Gaertn封装的球形CeO2纳米颗粒。花提取物及其对HCT 116人结肠癌细胞的体外抗癌活性。

氧化铈纳米颗粒（CeO ₂ NPs）的绿色合成已使用莲lum提取物作为封端剂和还原剂进行。使用紫外可见光谱法（UV-Vis）测定光学性质。根据傅立叶变换红外光谱（FTIR），在506 cm ^-1处的特征峰证实了Ce-O键的存在。通过FT-拉曼光谱确认萤石型立方结构。使用粉末X射线衍射仪（PXRD）鉴定结晶相。CeO ₂的稳定性和粒径使用动态光散射（DLS）分析来解释NP。使用高分辨率扫描电子显微镜（HRSEM）和高分辨率透射电子显微镜（HRTEM）技术分析粒径，形状和表面纹理。选定区域电子衍射（SAED）模式通过P-XRD数据确认了晶相的身份。元素映射是通过使用能量色散X射线（EDX）分析完成的。使用热重差热分析仪（TG-DTA）技术分析CeO ₂ NP的热行为。在体外的CeO细胞毒性作用₂纳米颗粒是使用MTT测定针对HCT 116人结肠癌细胞系测试。据记录，CeO _2的IC50NPs为41.60 µg / mL。在46小时内以40 µg / mL将62％的细胞活力降至最低。该结果提高了使用绿色环保方法合成具有有效抗癌活性的CeO ₂ NP的重要性。