Titanium oxide nanoparticles (TiO₂ NPs) have been attracting numerous research studies due to their activity; however, there is a growing concern about the corresponding toxicity. Here in the present study, titanium oxide nanoparticles were newly synthesized using propolis extract followed by antimicrobial activity, cytotoxicity assay using human cancer cell lines, and acute toxicity study. The physicochemical characterization of the newly synthesized TiO₂ NPs had average size = 57.5 nm, PdI = 0.308, and zeta potential = −32.4 mV. Antimicrobial activity assessment proved the superior activity against Gram-positive compared to Gram-negative bacteria and yeast (lowest MIC values 8, 32, and 32, respectively). The newly synthesized TiO₂ NPs showed a potent activity against the following human cancer cell lines: liver (HepG-2) (IC50 8.5 µg/mL), colon (Caco-2), and breast (MDA-MB 231) (IC50 11.0 and 18.7 µg/mL). In vivo acute toxicity study was conducted using low (10 mg/kg) and high (1000 mg/kg) doses of the synthesized TiO₂ NPs in albino male rats. Biochemistry and histopathology of the liver, kidney, and brain proved the safety of the synthesized TiO₂ NPs at low dose while at high dose, there was TiO₂ NPs deposit in different vital organs except the cerebral tissue.

中文翻译：

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氧化钛纳米粒子的新合成：生物活性和急性毒性研究

氧化钛纳米粒子（TiO ₂ NPs）因其活性而吸引了大量研究。然而，人们越来越担心相应的毒性。在本研究中，使用蜂胶提取物新合成氧化钛纳米粒子，然后进行抗菌活性、使用人类癌细胞系的细胞毒性测定和急性毒性研究。新合成的 TiO ₂ NPs的物理化学特征具有平均尺寸 = 57.5 nm、PdI = 0.308 和 zeta 电位 = -32.4 mV。抗菌活性评估证明，与革兰氏阴性菌和酵母菌相比，其对革兰氏阳性菌的活性更高（最低 MIC 值分别为 8、32 和 32）。新合成的 TiO ₂的NP显示出对下面的人癌症细胞系的强效活性：肝脏（人肝癌HepG-2）（IC 50 8.5  μ克/毫升），结肠（的Caco-2）和乳腺癌（MDA-MB 231）（IC50 11.0和18.7  μ克/毫升）。在白化雄性大鼠中使用低 (10 mg/kg) 和高 (1000 mg/kg) 剂量的合成 TiO ₂ NPs进行体内急性毒性研究。肝脏、肾脏和大脑的生化和组织病理学证明了合成的 TiO ₂ NPs 在低剂量下是安全的，而在高剂量下，除脑组织外，其他重要器官都有 TiO ₂ NPs 沉积。