Department of Chemistry, College of Chemistry and Environmental Engineering, Shenzhen University, Shenzhen 518060, China.
Longgang District Central Hospital of Shenzhen, Shenzhen 518116, China.
Biosensors (Basel). 2023 Apr 30;13(5):515. doi: 10.3390/bios13050515.
Alzheimer's disease (AD) is an irreversible neurodegenerative disease with clinical symptoms of memory loss and cognitive impairment. Currently, no effective drug or therapeutic method is available for curing this disease. The major strategy used is to identify and block AD at its initial stage. Thus, early diagnosis is very important for intervention of the disease and assessment of drug efficacy. The gold standards of clinical diagnosis include the measurement of AD biomarkers in cerebrospinal fluid and positron emission tomography imaging of the brain for amyloid-β (Aβ) deposits. However, these methods are difficult to apply to the general screening of a large aging population because of their high cost, radioactivity and inaccessibility. Comparatively, blood sample detection is less invasive and more accessible for the diagnosis of AD. Hence, a variety of assays based on fluorescence analysis, surface-enhanced Raman scattering, electrochemistry, etc., were developed for the detection of AD biomarkers in blood. These methods play significant roles in recognizing asymptomatic AD and predicting the course of the disease. In a clinical setting, the combination of blood biomarker detection with brain imaging may enhance the accuracy of early diagnosis. Fluorescence-sensing techniques can be used not only to detect the levels of biomarkers in blood but also to image biomarkers in the brain in real time due to their low toxicity, high sensitivity and good biocompatibility. In this review, we summarize the newly developed fluorescent sensing platforms and their application in detecting and imaging biomarkers of AD, such as Aβ and tau in the last five years, and discuss their prospects for clinical applications.
阿尔茨海默病（AD）是一种不可逆的神经退行性疾病，其临床症状为记忆丧失和认知障碍。目前，尚无有效的药物或治疗方法可以治愈这种疾病。主要策略是在疾病的早期发现和阻断。因此，早期诊断对于干预疾病和评估药物疗效非常重要。临床诊断的金标准包括测量脑脊液中的 AD 生物标志物和大脑的正电子发射断层扫描成像以检测淀粉样蛋白-β（Aβ）沉积。然而，由于这些方法成本高、具有放射性且难以获得，因此难以应用于一般老龄化人群的广泛筛查。相比之下，血液样本检测对于 AD 的诊断具有较少的侵入性和更好的可及性。因此，开发了各种基于荧光分析、表面增强拉曼散射、电化学等的检测血液中 AD 生物标志物的方法。这些方法在识别无症状 AD 和预测疾病进程方面发挥了重要作用。在临床环境中，将血液生物标志物检测与脑成像相结合可能会提高早期诊断的准确性。由于荧光传感技术具有低毒性、高灵敏度和良好的生物相容性，因此不仅可以用于检测血液中生物标志物的水平，还可以实时对大脑中的生物标志物进行成像。在本篇综述中，我们总结了过去五年中用于检测和成像 AD 生物标志物（如 Aβ和 tau）的新型荧光传感平台及其应用，并讨论了它们在临床应用中的前景。
