Screening of inhibitors that slow down or suppress amyloid fibrils formation relies on some simple but sensitive spectroscopy techniques. Thioflavin T (ThT) fluorescence assay is one of the most common, amyloid specific and sensitive method. However, if an inhibitor is itself fluorescent in the ThT fluorescence range, its screening becomes complicated and require complementary assays. One of such molecules, 6, 7-dihydroxycoumarin (6, 7-DHC, also known as aesculetin, esculetin, and cichorigenin) is fluorescent in the ThT emission range and absorbs in the ThT excitation range. Therefore, it can produce a subtractive effect attributed to primary inner filter effect and/or additive effect due to its self-fluorescence in ThT assay. Our study shows that 6, 7-DHC produces an additive effect in ThT fluorescence, which is minimized at high concentration of ThT and decrease in ThT fluorescence is solely due to its inhibitory effect against HSA fibrillation. These ThT fluorescence-based results are verified through other complementary assays, such as Rayleigh and dynamic light scattering and amyloid-specific Congo red binding assay. Furthermore, hydrophobicity reduction is studied through Nile red (NR) and kinetics through far-UV circular dichroism (far-UV CD) in place of the most commonly employed ThT assay owing to extremely high fluorescence of 6, 7-DHC during initial incubation period.

减缓或抑制淀粉样蛋白原纤维形成的抑制剂的筛选依赖于一些简单但灵敏的光谱技术。硫磺素 T (ThT) 荧光检测是最常见的淀粉样蛋白特异性和敏感方法之一。然而，如果抑制剂本身在 ThT 荧光范围内发出荧光，则其筛选变得复杂并需要补充检测。其中一种分子 6, 7-二羟基香豆素（6, 7-DHC，也称为七叶亭、七叶亭和菊苣素）在 ThT 发射范围内发出荧光，并在 ThT 激发范围内吸收。因此，由于其在 ThT 测定中的自发荧光，它可以产生归因于初级内部过滤效应和/或加法效应的减法效应。我们的研究表明 6, 7-DHC 在 ThT 荧光中产生累加效应，其在高浓度 ThT 下最小化并且 ThT 荧光的降低仅是由于其对 HSA 纤颤的抑制作用。这些基于 ThT 荧光的结果已通过其他补充分析进行验证，例如瑞利和动态光散射以及淀粉样蛋白特异性刚果红结合分析。此外，由于 6, 7-DHC 在初始孵育期间具有极高的荧光，因此通过尼罗红 (NR) 和通过远紫外圆二色性 (far-UV CD) 代替最常用的 ThT 测定来研究疏水性降低. 例如瑞利和动态光散射以及淀粉样蛋白特异性刚果红结合测定。此外，由于 6, 7-DHC 在初始孵育期间具有极高的荧光，因此通过尼罗红 (NR) 和通过远紫外圆二色性 (远紫外 CD) 的动力学代替最常用的 ThT 测定来研究疏水性降低. 例如瑞利和动态光散射以及淀粉样蛋白特异性刚果红结合测定。此外，由于 6, 7-DHC 在初始孵育期间具有极高的荧光，因此通过尼罗红 (NR) 和通过远紫外圆二色性 (远紫外 CD) 的动力学代替最常用的 ThT 测定来研究疏水性降低.