State Key Laboratory of Supramolecular Structure and Materials, Institute of Theoretical Chemistry, Jilin University, No. 2699 Qianjin Street, Changchun 130012, China.
School of Biomedical Sciences, Li Ka Shing Faculty of Medicine, The University of Hong Kong, Pokfulam, Hong Kong S. A. R., China.
Analyst. 2017 Feb 27;142(5):800-807. doi: 10.1039/c6an02417c.
Innovative nanomaterials offer significant potential for diagnosis of severe diseases of the developing world such as malaria. Small sized silver nanoclusters have shown promise for diagnostics due to their intense fluorescence emission and photo-stabilities. Here, double-stranded DNA-scaffolded silver nanoclusters (AgNCs-dsDNA) were prepared to detect the established malaria biomarker, Plasmodium falciparum lactate dehydrogenase (PfLDH). Significant luminescence enhancement over a wide concentration range of PfLDH was demonstrated. In addition, a low limit of detection at 0.20 nM (7.4 pg μL) was achieved for PfLDH in buffer solution, sensitive enough for practical use correlating with the clinical level of PfLDH in plasma from malaria-infected patients. Unique specificity was observed towards Plasmodium falciparum over Plasmodium vivax and human lactate dehydrogenase, as well as other non-specific proteins, by combining the use of AgNCs-dsDNA with a DNA aptamer against PfLDH. Moreover, the intrinsic mechanism was revealed in detail for the two-step luminescence response. The combination of DNA-scaffolded silver nanoclusters coupled to a selective single-stranded DNA aptamer allows for a highly specific and sensitive detection of PfLDH with significant promise for malaria diagnosis in future.
创新性纳米材料为发展中国家严重疾病（如疟疾）的诊断提供了巨大的潜力。由于其强烈的荧光发射和光稳定性，小尺寸的银纳米簇在诊断方面显示出了很大的希望。在这里，制备了双链 DNA 支架银纳米簇（AgNCs-dsDNA）以检测已建立的疟疾生物标志物，即恶性疟原虫乳酸脱氢酶（PfLDH）。AgNCs-dsDNA 对 PfLDH 表现出了在很宽浓度范围内的显著发光增强。此外，在缓冲溶液中 PfLDH 的检测限低至 0.20 nM（7.4 pg μL），足以与来自疟疾感染患者的血浆中的 PfLDH 临床水平相关联，具有实际应用的灵敏度。通过将 AgNCs-dsDNA 与针对 PfLDH 的 DNA 适体结合使用，观察到对恶性疟原虫的独特特异性，而对间日疟原虫和人乳酸脱氢酶以及其他非特异性蛋白质没有特异性。此外，还详细揭示了两步发光响应的内在机制。DNA 支架银纳米簇与选择性单链 DNA 适体的结合允许对 PfLDH 进行高度特异性和灵敏的检测，为未来的疟疾诊断提供了巨大的希望。
