Wu Shuang, Kong Xiang-Juan, Cen Yao, Yuan Jing, Yu Ru-Qin, Chu Xia
State Key Laboratory of Chemo/Bio-Sensing and Chemometrics, College of Chemistry and Chemical Engineering, Hunan University, Changsha, 410082, P. R. China.
Nanoscale. 2016 Apr 28;8(16):8939-46. doi: 10.1039/c6nr00470a.
Blood glucose detecting has aroused considerable attention because diabetes mellitus has become a worldwide publish health problem. Herein, we construct an exceptionally simple upconverting hybrid nanocomposite, composed of DNA-templated Ag nanoparticles (DNA-AgNPs) and NaYF4:Yb/Tm@NaYF4 core-shell upconversion nanoparticles (UCNPs), for the sensing of H2O2 and glucose. In this design, UCNPs with bared surface act as the donor, and DNA-AgNPs serve as efficient quenchers. DNA-AgNPs can be directly assembled on the bared surface of UCNPs, which further decreases the distance of donor-to-acceptor. The formation of DNA-AgNPs/UCNP nanocomposite results in luminescence quenching of UCNP by DNA-AgNPs through luminescence resonance energy transfer (LRET). Upon H2O2 addition, AgNPs can be etched and transformed into Ag(+), leading to inhibition of the LRET process and causing the recovery of upconversion luminescence. Based on the conversion of glucose into H2O2 by glucose oxidase, the DNA-AgNPs/UCNP nanocomposite can also be exploited for glucose sensing. Moreover, due to the non-autofluorescence offered by UCNPs, the approach developed can be applied to monitor glucose levels in human serum samples with satisfactory results.
由于糖尿病已成为一个全球性的公共卫生问题，血糖检测引起了广泛关注。在此，我们构建了一种极其简单的上转换杂化纳米复合材料，它由DNA模板化的银纳米颗粒（DNA-AgNPs）和NaYF4:Yb/Tm@NaYF4核壳上转换纳米颗粒（UCNPs）组成，用于检测H2O2和葡萄糖。在这种设计中，表面裸露的UCNPs作为供体，而DNA-AgNPs作为高效的猝灭剂。DNA-AgNPs可以直接组装在UCNPs的裸露表面上，这进一步缩短了供体与受体之间的距离。DNA-AgNPs/UCNP纳米复合材料的形成导致DNA-AgNPs通过发光共振能量转移（LRET）使UCNP的发光猝灭。加入H2O2后，AgNPs会被蚀刻并转化为Ag(+)，导致LRET过程受到抑制，从而使上转换发光恢复。基于葡萄糖氧化酶将葡萄糖转化为H2O2的反应，DNA-AgNPs/UCNP纳米复合材料也可用于葡萄糖传感。此外，由于UCNPs不具有自发荧光，所开发的方法可用于监测人血清样本中的葡萄糖水平，结果令人满意。
