The misfolding and aggregation of proteins leading to amyloid formation has been linked to numerous diseases, necessitating the development of tools to monitor the fibrillation process. Here, we report an intramolecular charge transfer (ICT) dye, DMNDC, as an alternative to thioflavin-T (ThT), most commonly used for monitoring amyloid fibrils. Using insulin as a model protein, we show that DMNDC efficiently reports on the kinetics of fibril formation. An approximately 70 nm hypsochromic shift along with a large enhancement in emission intensity was observed upon binding of DMNDC to protein fibrils. The aggregation kinetics of insulin were not significantly affected in the presence of DMNDC, suggesting that DMNDC does not inhibit insulin aggregation. Additionally, the efficient cellular internalization and low toxicity of DMNDC make it highly suited for sensing and imaging of amyloid fibrils in the complex biological milieu.

中文翻译：

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生物相容性荧光探针，可选择性检测淀粉样蛋白原纤维。

导致淀粉样蛋白形成的蛋白质的错误折叠和聚集与多种疾病有关，因此需要开发监测原纤维形成过程的工具。在这里，我们报道了一种分子内电荷转移（ICT）染料DMNDC，它是最常用于监测淀粉样蛋白原纤维的硫代黄素T（ThT）的替代品。使用胰岛素作为模型蛋白，我们表明DMNDC有效地报告了原纤维形成的动力学。DMNDC与蛋白质原纤维结合后，观察到约70 nm的变色位移以及发射强度的大幅提高。在DMNDC存在下，胰岛素的聚集动力学没有受到显着影响，这表明DMNDC不抑制胰岛素聚集。另外，