In this study, a novel p-hydroxybenzylidene-imidazolidone derivatives-based probe CBX (abbreviation of the synthetic probe) is designed and synthesized for sensitive detection of protamine. CBX emits fluorescence at 569 nm and a large Stokes shift of 114 nm is observed. Since protamine can induce the aggregation of negatively charged CBX, the designed probe shows excellent fluorescent response to protamine. Due to stronger electrostatic interactions between heparin and protamine, protamine prefers to unite with heparin rather than the probe after the addition of heparin, so the fluorescence of CBX decreases and realizes the detection of heparin. Comparing to other reported probes, CBX shows lower background interference, better sensitivity and higher stability. Limit of detection for protamine and heparin is calculated as 0.034 and 0.028 μg mL⁻¹, respectively. Moreover, the detection of protamine by CBX is not interfered by other glycosaminoglycans.

中文翻译：

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基于黄色发射荧光团的鱼精蛋白的灵敏检测

在这项研究中，一个新的p-羟基亚苄基咪唑烷酮衍生物探针CBX（合成探针的缩写）是为灵敏检测鱼精蛋白而设计和合成的。CBX 在 569 nm 处发出荧光，并观察到 ​​114 nm 的大斯托克斯位移。由于鱼精蛋白可以诱导带负电荷的 CBX 的聚集，因此设计的探针对鱼精蛋白显示出优异的荧光响应。由于肝素与鱼精蛋白之间的静电作用较强，加入肝素后鱼精蛋白更倾向于与肝素结合而不是与探针结合，因此CBX的荧光减弱，实现了对肝素的检测。与其他报道的探针相比，CBX 显示出更低的背景干扰、更好的灵敏度和更高的稳定性。鱼精蛋白和肝素的检测限计算为 0.034 和 0.028 μg mL ^-1， 分别。此外，CBX 对鱼精蛋白的检测不受其他糖胺聚糖的干扰。