Key Laboratory of Optoelectronic Science and Technology for Medicine of Ministry of Education, Provincial Key Laboratory for Photonics Technology, Fujian Normal University, Fuzhou, 350007, China.
Key Laboratory of Optoelectronic Science and Technology for Medicine of Ministry of Education, Provincial Key Laboratory for Photonics Technology, Fujian Normal University, Fuzhou, 350007, China.
Talanta. 2020 Jun 1;213:120815. doi: 10.1016/j.talanta.2020.120815. Epub 2020 Feb 10.
Lead ions are deleterious pollutants that often reach drinking water, and can cause significant harm to humans (particularly children). An ultra-sensitive lead ion detection method using a whispering gallery mode (WGM) optofluidic microbubble resonator and the classic GR-5 DNAzyme is proposed in this paper. With the auxiliary piranha and Ploy-l-lysine solution, GR-5 DNAzyme was successfully modified on the inner wall of a microbubble. The mode field distribution of the microbubble was analysed, and the optofluidic sensor with thin wall exhibited a maximum bulk refractive index sensitivity of 265.2 nm/RIU. Lead ions at concentrations ranging from 0.1 pM to 100 pM were tested using the proposed WGM optofluidic sensor. The noise was decreased to 2.43 fM using the self-referenced differential method. Thus, a limit of approximately 15 fM was obtained for the detection of lead ions using the WGM optofluidic biosensor. Eight competing metal ions were also used to evaluate the selectivity of the proposed sensor, with results indicating that it has high selectivity for lead ions. Finally, the sensor performance is verified using real samples.
铅离子是有害的污染物，经常会进入饮用水中，对人体（尤其是儿童）造成严重危害。本文提出了一种基于声谐振模式（WGM）光流体微泡谐振器和经典 GR-5 DNA 酶的超灵敏铅离子检测方法。通过辅助的过氧酸和聚赖氨酸溶液，GR-5 DNA 酶成功地修饰在了微泡的内壁上。分析了微泡的模场分布，具有薄壁的光流体传感器表现出最大的体折射率灵敏度为 265.2nm/RIU。利用所提出的 WGM 光流体传感器，测试了浓度范围从 0.1pM 到 100pM 的铅离子。采用自参考差分法，将噪声降低到 2.43fM。因此，使用 WGM 光流体生物传感器检测铅离子的检测限约为 15fM。还使用了八种竞争金属离子来评估所提出传感器的选择性，结果表明其对铅离子具有高选择性。最后，使用实际样品验证了传感器性能。
