Haribabu Viswanathan, Sharmiladevi Palani, Akhtar Najim, Farook Abubacker Sulaiman, Girigoswami Koyeli, Girigoswami Agnishwar
Faculty of Allied Health Sciences, Chettinad Hospital and Research Institute (CHRI), Chettinad Academy of Research & Education (CARE), Kelambakkam, Chennai 603 103, India.
Department of Radiology, Chettinad Hospital & Research Institute (CHRI), Kelambakkam, Chennai 603 103, India.
Curr Drug Deliv. 2019;16(3):233-241. doi: 10.2174/1567201816666181119112410.
The label free ultrasmall fluorescent ferrite clusters have been engineered in a controlled fashion which was stabilized by serum protein and functionalized by folic acid for the application of targeted multimodal optical and Magnetic Resonance (MR) cancer imaging.
The ultra-small manganese ferrite nanoclusters (PMNCs) with a diameter of 4 nm have a commendable effect on the longitudinal (T1) and transverse (T2) relaxation in MR imaging that was evident from the phantom and animal MRI.
The calculated longitudinal molar relaxivity of nanoclusters was found to be 6.9 ± 0.10 mM-1 S-1 which was exactly 2.22 times better than the conventional Gd-DOTA and their 4.01 ratio of the transverse (r2) and longitudinal (r1) relaxivities made them a potential candidate for both T1 and T2 contrast agents in MRI. In addition, the fluorescence-based small animal imaging showed folic acid driven accumulated fluorescent signal at the tumour site to conclude the capacity of PMNCs for targeted fluorescence imaging of cancer diagnosis.
The cytotoxicity assay and histopathology studies were the evidence for their safe biodistribution in animal systems. Furthermore, the protein encapsulated clusters have the ability to deliver the anticancer drug Methotrexate (MTX) to the cancer tissues with a sustained manner. Therefore, one can conclude the remarkable efficacy of architect nanoclusters for theragnosis.
已通过可控方式构建了无标记的超小荧光铁氧体簇，该簇由血清蛋白稳定并经叶酸功能化，用于靶向多模态光学和磁共振（MR）癌症成像。
直径为4 nm的超小锰铁氧体纳米簇（PMNCs）在MR成像中对纵向（T1）和横向（T2）弛豫具有显著效果，这在体模和动物MRI中很明显。
发现纳米簇的计算纵向摩尔弛豫率为6.9±0.10 mM-1 S-1，比传统的钆-多胺多羧络合剂（Gd-DOTA）高出2.22倍，其横向（r2）与纵向（r1）弛豫率的4.01比例使其成为MRI中T1和T2造影剂的潜在候选者。此外，基于荧光的小动物成像显示叶酸驱动肿瘤部位荧光信号积累，从而证实了PMNCs用于癌症诊断靶向荧光成像的能力。
细胞毒性试验和组织病理学研究证明了它们在动物系统中的安全生物分布。此外，蛋白质包裹的簇能够持续将抗癌药物甲氨蝶呤（MTX）递送至癌组织。因此，可以得出构建纳米簇在诊疗方面具有显著疗效的结论。
