Hence, in this study, the authors aimed to develop a dendrimer-based imaging agent comprised of poly(ethylene glycol) (PEG)-citrate, technetium-99 m ( ^99m Tc), and folic acid. The dendrimer-G3 was synthesised and conjugated with folic acid, which confirmed by Fourier transform infrared, proton nuclear magnetic resonance, dynamic light scattering, and transition electron microscopy. 2,3-bis-(2-methoxy-4-nitro-5-sulfophenyl)-2H-Tetrazolium-5-Carboxanilide cytotoxicity assay kit was used to measure the cellular toxicity of dendrimer. Imaging and biodistribution studies were conducted on the mice bearing tumour. The results showed that the fabricated dendrimer-G3 has a size of 90 ± 3 nm, which was increased to 100 ± 4 nm following the conjugation with folic acid. The radiostablity investigation showed that the fabricated dendrimers were stable in the human serum at various times. Toxicity assessment confirmed no cellular toxicity against HEK-293 cells at 0.25, 0.5, 1, 2, 4, and 8 mg/μl concentrations. The in vivo studies demonstrated that the synthesised dendrimers were able to provide a bright SPECT image applicable for tumour detection. In conclusion, the authors’ study documented the positive aspects of PEG-citrate dendrimer conjugated with folic acid as the SPECT contrast agent for breast cancer detection.

中文翻译：

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叶酸缀合的 G-3 99mTc-树枝状乳腺癌分子显像剂的合成、放射性标记和生物学评估


因此，在这项研究中，作者旨在开发一种基于树枝状聚合物的显像剂，由聚乙二醇 (PEG)-柠檬酸酯、technetium-99 m ( ^99m Tc) 和叶酸组成。合成了树枝状大分子-G3并与叶酸缀合，并通过傅里叶变换红外、质子核磁共振、动态光散射和过渡电子显微镜证实。使用2,3-双-(2-甲氧基-4-硝基-5-磺基苯基)-2H-四唑鎓-5-甲酰苯胺细胞毒性测定试剂盒测定树枝状聚合物的细胞毒性。对携带肿瘤的小鼠进行了成像和生物分布研究。结果表明，制备的树枝状聚合物-G3的尺寸为90±3nm，与叶酸缀合后尺寸增加至100±4nm。放射稳定性研究表明，所制备的树枝状聚合物在不同时间的人血清中都是稳定的。毒性评估证实，在 0.25、0.5、1、2、4 和 8 mg/μl 浓度下，对 HEK-293 细胞没有细胞毒性。体内研究表明，合成的树枝状聚合物能够提供适用于肿瘤检测的明亮 SPECT 图像。总之，作者的研究记录了与叶酸缀合的 PEG-柠檬酸盐树枝状聚合物作为 SPECT 造影剂用于乳腺癌检测的积极方面。