Mirzaei Seyedeh Mozhdeh, Oskuee Reza Kazemi, Sadri Kayvan, Sabouri Zahra, Far Bahareh Farasati, Abdulabbas Hadi Sajid, Darroudi Majid
Department of Medical Biotechnology & Nanotechnology, Faculty of Medicine, Mashhad University of Medical Sciences, Mashhad, Iran.
Nuclear Medicine Research Center, Mashhad University of Medical Sciences, Mashhad, Iran.
Appl Biochem Biotechnol. 2024 Jun;196(6):3356-3373. doi: 10.1007/s12010-023-04703-7. Epub 2023 Aug 31.
Sulfur quantum dots (SQDs) as free heavy metal element quantum dots have promising applications in diagnosis and therapy; however, SQDs' in vivo biodistribution has not been studied. In the current study, SQDs were synthesized directly from cheap sublimated sulfur powder via a one-pot solvothermal method, and sucrose was used as a stabilizer to enhance stability and biocompatibility. The as-obtained SQDs with an average size of 4.6 nm exhibited great water dispersity, highly favorable quantum yield (21.5%), and uniformly spherical shape which were confirmed by UV-Vis, fluorescence spectrophotometer, TEM, and FESEM/EDX/PSA analyses. Moreover, the as-synthesized SQDs had very low cytotoxicity based on cancer (C26) and normal (L929) cell lines via MTT assay. And also, SQDs were radio-labeled directly by Technetium-99m (Tc), which had good stability ranging from 86 to 99% in PBS and human serum. The SQDs' cell uptake on C26 and L929 cell lines demonstrated that cancer cells had more uptake than normal cells by increasing concentrations. Moreover, SQDs' in vivo biodistribution results displayed high kidney dose accumulation and rapid renal clearance, making them suitable for imaging and therapeutic applications.
硫量子点（SQDs）作为不含重金属元素的量子点在诊断和治疗方面具有广阔的应用前景；然而，尚未对SQDs在体内的生物分布进行研究。在本研究中，通过一锅溶剂热法直接由廉价的升华硫粉合成了SQDs，并使用蔗糖作为稳定剂来提高稳定性和生物相容性。通过紫外可见光谱、荧光分光光度计、透射电子显微镜以及场发射扫描电子显微镜/能谱仪/光电子能谱分析证实，所获得的平均尺寸为4.6 nm的SQDs表现出良好的水分散性、较高的量子产率（21.5%）以及均匀的球形形状。此外，通过MTT法检测，所合成的SQDs对癌症（C26）和正常（L929）细胞系的细胞毒性非常低。而且，SQDs通过99m锝（Tc）直接进行放射性标记，其在磷酸盐缓冲液和人血清中的稳定性良好，范围在86%至99%之间。SQDs在C26和L929细胞系上的细胞摄取情况表明，随着浓度增加，癌细胞的摄取量比正常细胞更多。此外，SQDs的体内生物分布结果显示肾脏剂量积累高且肾脏清除迅速，这使其适用于成像和治疗应用。
