Mazaheri Tehrani Maryam, Erfani Mostafa, Amiri Mojtaba, Goudarzi Mostafa
Radiation Application Research School, Nuclear Science and Technology Research Institute, Tehran, Iran.
Int J Radiat Biol. 2025;101(1):65-72. doi: 10.1080/09553002.2024.2404460. Epub 2024 Sep 26.
Cancer diagnosis involves a multi-step process. Accurate identification of the tumor, staging and development of cancer cells is crucial for selecting optimal treatments to minimize disease recurrence. Quantum dots (QDs) represent an exciting class of fluorescent nanoprobes in molecular detection and targeted tumor imaging.
In this study, graphene quantum dots (GQDs) were synthesized by pyrolysis of citric acid (CA) as a carbon precursor under high temperatures. The morphology of the obtained GQDs was first characterized using physical (TEM and DLS) and spectroscopic (fluorescence, FTIR and UV-Vis) methods. In the following,Tc-labeled GQDs were prepared in the presence of SnCl.2HO as a reducing agent between 95 and 100 °C. The biodistribution and tumor targeting efficiency of radiolabeled GQDs as a novel agent for C6 glioma tumor scintigraphy in an animal model were evaluated. Furthermore, organ uptake, human serum albumin binding and tumor accumulation were measured.
The TEM image of the prepared GQDs showed a relatively uniform size distribution in the range of diameter 6-9 nm and spherical shape. Radiolabeled GQDs showed a radiochemical yield of >97% ( = 3). Through incubation in human serum, almost 15% of Tc-labeled GQDs degraded after 6 h. The amount of uptake in xenograft models of glioma C6 rats was 1.10 ± 0.36% of injection dose per gram after 1 h. The kidneys, intestinal and glioma tumor sites were observed via scintigraphy imaging.
Our data suggest that Tc-labeled GQDs, as a new radiotracer, efficiently accumulate in the tumor site and could be included as a radiotracer for detecting glioma tumors.
癌症诊断涉及多个步骤。准确识别肿瘤、癌细胞的分期和发展对于选择最佳治疗方案以尽量减少疾病复发至关重要。量子点（QDs）是分子检测和靶向肿瘤成像中一类令人兴奋的荧光纳米探针。
在本研究中，以柠檬酸（CA）作为碳前驱体，通过高温热解合成了石墨烯量子点（GQDs）。首先使用物理方法（透射电子显微镜和动态光散射）和光谱方法（荧光、傅里叶变换红外光谱和紫外可见光谱）对所得GQDs的形态进行表征。接下来，在95至100°C的条件下，以二水合氯化亚锡作为还原剂制备锝标记的GQDs。评估了放射性标记的GQDs作为动物模型中C6胶质瘤肿瘤闪烁显像新型试剂的生物分布和肿瘤靶向效率。此外，还测量了器官摄取、人血清白蛋白结合和肿瘤蓄积情况。
制备的GQDs的透射电子显微镜图像显示，其直径在6 - 9nm范围内尺寸分布相对均匀，呈球形。放射性标记的GQDs显示放射化学产率>97%（=3）。在人血清中孵育后，6小时后几乎15%的锝标记GQDs降解。1小时后，C6大鼠胶质瘤异种移植模型中的摄取量为每克注射剂量的1.10±0.36%。通过闪烁显像观察到肾脏、肠道和胶质瘤肿瘤部位。
我们的数据表明，锝标记的GQDs作为一种新的放射性示踪剂，能有效地在肿瘤部位蓄积，可作为检测胶质瘤肿瘤的放射性示踪剂。
