Ischaemic stroke and glioma, as leading causes of mortality and long-term disability, pose critical challenges to healthcare systems, necessitating innovative approaches to enable early and cost-effective diagnosis for timely intervention. Glial fibrillary acidic protein (GFAP), an astrocyte-produced protein, is highly responsive to both ischaemic stroke and glioblastoma multiforme, with its levels correlating to the extent of brain damage. In this study, we present the development of an immunoassay probe for the ratiometric fluorescent detection of glial fibrillary acidic protein (GFAP), employing a monoclonal GFAP antibody-conjugated silicon quantum dots (Ab@SiQDs) and rhodamine B dye (RhB)-based immunoprobe. The developed probe exhibited a fluorescence emission shift from 580 nm to 530 nm in response to GFAP, demonstrating a linear detection range from 31.15 pg mL⁻¹ to 243 pg mL⁻¹, with a limit of detection of 0.7 pg mL⁻¹. Additionally, the immunoprobe showed high selectivity for GFAP, effectively discriminating it from other potential interfering biomolecules and ions. The probe was also capable of detecting GFAP in spiked serum samples, achieving a recovery rate ranging from 83% to 111%. Notably, a cost-effective paper strip assay was developed, offering significant potential for the visual detection of GFAP under ultraviolet illumination.

中文翻译：

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基于量子点-染料的 GFAP 荧光比率免疫测定：缺血性卒中和多形性胶质母细胞瘤的生物标志物


缺血性中风和神经胶质瘤是导致死亡和长期残疾的主要原因，对医疗保健系统构成了重大挑战，需要创新方法来实现早期和具有成本效益的诊断，以便及时干预。神经胶质纤维酸性蛋白 （GFAP） 是一种星形胶质细胞产生的蛋白质，对缺血性中风和多形性胶质母细胞瘤都高度敏感，其水平与脑损伤的程度相关。在这项研究中，我们提出了一种免疫测定探针的开发，用于胶质纤维酸性蛋白 （GFAP） 的比率荧光检测，采用单克隆 GFAP 抗体偶联的硅量子点 （Ab@SiQDs） 和基于罗丹明 B 染料 （RhB） 的免疫探针。开发的探针响应 GFAP 表现出从 580 nm 到 530 nm 的荧光发射偏移，线性检测范围为 31.15 pg ^mL-1 至 243 pg ^mL-1，检测限为 0.7 pg ^mL-1。此外，免疫探针对 GFAP 具有高选择性，可有效将其与其他潜在干扰生物分子和离子区分开来。该探针还能够检测加标血清样品中的 GFAP，回收率为 83% 至 111%。值得注意的是，开发了一种具有成本效益的纸条测定法，为在紫外线照射下目视检测 GFAP 提供了巨大的潜力。