Department of Applied Physics, The Hong Kong Polytechnic University , Hung Hom, Kowloon, Hong Kong, P. R. China.
Interdisciplinary Division of Biomedical Engineering, The Hong Kong Polytechnic University , Hung Hom, Kowloon, Hong Kong, P. R. China.
ACS Nano. 2016 Jan 26;10(1):598-605. doi: 10.1021/acsnano.5b05622. Epub 2016 Jan 6.
Ebola outbreaks are currently of great concern, and therefore, development of effective diagnosis methods is urgently needed. The key for lethal virus detection is high sensitivity, since early-stage detection of virus may increase the probability of survival. Here, we propose a luminescence scheme of assay consisting of BaGdF5:Yb/Er upconversion nanoparticles (UCNPs) conjugated with oligonucleotide probe and gold nanoparticles (AuNPs) linked with target Ebola virus oligonucleotide. As a proof of concept, a homogeneous assay was fabricated and tested, yielding a detection limit at picomolar level. The luminescence resonance energy transfer is ascribed to the spectral overlapping of upconversion luminescence and the absorption characteristics of AuNPs. Moreover, we anchored the UCNPs and AuNPs on a nanoporous alumina (NAAO) membrane to form a heterogeneous assay. Importantly, the detection limit was greatly improved, exhibiting a remarkable value at the femtomolar level. The enhancement is attributed to the increased light-matter interaction throughout the nanopore walls of the NAAO membrane. The specificity test suggested that the nanoprobes were specific to Ebola virus oligonucleotides. The strategy combining UCNPs, AuNPs, and NAAO membrane provides new insight into low-cost, rapid, and ultrasensitive detection of different diseases. Furthermore, we explored the feasibility of clinical application by using inactivated Ebola virus samples. The detection results showed great potential of our heterogeneous design for practical application.
埃博拉病毒爆发目前备受关注，因此急需开发有效的诊断方法。致命病毒检测的关键是高灵敏度，因为早期检测病毒可能会增加生存的概率。在这里，我们提出了一种由 BaGdF5:Yb/Er 上转换纳米粒子（UCNPs）与寡核苷酸探针偶联，以及与靶埃博拉病毒寡核苷酸连接的金纳米粒子（AuNPs）组成的发光分析方案。作为概念验证，我们制备并测试了一种均相分析方法，检测限达到皮摩尔水平。发光共振能量转移归因于上转换发光的光谱重叠和 AuNPs 的吸收特性。此外，我们将 UCNPs 和 AuNPs 固定在纳米多孔氧化铝（NAAO）膜上，形成了一种异质分析方法。重要的是，检测限大大提高，在飞摩尔水平显示出显著的值。这种增强归因于通过 NAAO 膜的纳米孔壁增加了光物质相互作用。特异性测试表明，纳米探针特异性地针对埃博拉病毒寡核苷酸。该策略结合了 UCNPs、AuNPs 和 NAAO 膜，为低成本、快速、超灵敏检测不同疾病提供了新的思路。此外，我们还通过使用灭活的埃博拉病毒样本探索了临床应用的可行性。检测结果表明，我们的异质设计在实际应用中具有很大的潜力。
