Suzhou Institute of Biomedical Engineering and Technology, Chinese Academy of Sciences, Suzhou 215163, P. R. China.
Nanoscale. 2019 Apr 25;11(17):8119-8123. doi: 10.1039/c9nr01307e.
There is an increasing demand to establish a convenient and stable analytical methodology for screening multiplex tumor markers in early diagnosis of cancers. In this work, an innovative fluorescence method is proposed for simultaneous detection of alpha-fetoprotein (AFP) and carcinoembryonic antigen (CEA). A polydopamine nanosphere@silver nanocluster (PDAN@AgNC) system is introduced for fluorescence quenching and recovery. The AgNCs with different emissions are synthesized using different DNA templates, which also contain aptamer sequences towards AFP and CEA, respectively. These single-stranded DNA sequences could be adsorbed on the surface of the PDAN through π-π stacking, which results in the quenching of AgNCs. However, in the presence of the corresponding tumor marker, the aptamer/target complex forms which releases AgNCs from the surface of the PDAN and the recovered fluorescence could be used to indicate the concentration of the tumor marker. This PDAN@AgNC system has been validated preliminarily to screen human serum samples with excellent results. Taking advantages of simplicity, enzyme/antibody-free nature, low cost and convenient operation, the proposed biosensor has great potential to be used in biomedical research studies and clinical diagnosis.
人们越来越希望建立一种方便、稳定的分析方法，用于筛选多种肿瘤标志物，以实现癌症的早期诊断。在这项工作中，我们提出了一种创新的荧光方法，用于同时检测甲胎蛋白（AFP）和癌胚抗原（CEA）。我们引入了聚多巴胺纳米球@银纳米簇（PDAN@AgNC）体系用于荧光猝灭和恢复。使用不同的 DNA 模板合成了具有不同发射的 AgNCs，这些 DNA 模板分别包含针对 AFP 和 CEA 的适体序列。这些单链 DNA 序列可以通过π-π堆积吸附在 PDAN 的表面，从而猝灭 AgNCs 的荧光。然而，在存在相应的肿瘤标志物时，适体/靶复合物形成，AgNCs 从 PDAN 表面释放出来，恢复的荧光可用于指示肿瘤标志物的浓度。该 PDAN@AgNC 体系已初步验证可用于筛选人血清样品，结果令人满意。该生物传感器具有简单、无需酶/抗体、成本低、操作方便等优点，在生物医学研究和临床诊断中有很大的应用潜力。
