College of Physics and Optoelectronics Engineering, Dalian University of Technology, Dalian 116024, China.
School of Chemistry, Dalian University of Technology, Dalian 116024, China.
Biosens Bioelectron. 2018 Oct 15;117:637-643. doi: 10.1016/j.bios.2018.06.042. Epub 2018 Jun 25.
A highly sensitive surface plasmon resonance (SPR) sensor is reported for glucose detection using self-assembled p-mercaptophenylboronic acid (PMBA) monolayer on Au coated optical fibers. The cis-diol group of saccharides, such as for glucose, interacted with the self-assembled PMBA monolayers on the optical fibers, but the low molecular mass of glucose is insufficient for measuring a significant shift in SPR wavelength. The response for glucose was thus enhanced with Au nanoparticles (Au NPs) modified with 2-aminoethanethiol (AET) and PMBA. Selectivity was assured since glucose has the ability to capture the signal amplification tags (Au NPs/AET- PMBA) through secondary binding with another set of syn-periplanar diol groups and the PMBA on the gold surface. Accordingly, a glucose concentration-dependent sandwich structure was formed and the coupling between Au NPs and Au film results in the red shift of SPR resonance wavelength. The experimental results demonstrated that this SPR sensor responded to glucose within a range of 0.01-30 mM better than to fructose and galactose. The minimum concentration for quantify glucose is as low as 80 nM, which is lower than the physiological blood glucose level. Glucose was then accurately detected in urine sample, which indicated the potential application of the sensor for the analysis of glucose in urine. We believe that our proposed PMBA-modified single amplification tag and sensing principle can also be used for biomolecules consisting of carbohydrate structures, particularly for DNA-associated bioanalysis.
本文报道了一种基于自组装巯基苯硼酸（PMBA）单层修饰金涂覆光纤的高灵敏度表面等离子体共振（SPR）传感器，用于葡萄糖检测。糖的顺式二醇基团，如葡萄糖，与光纤上的自组装 PMBA 单层相互作用，但葡萄糖的低相对分子质量不足以测量 SPR 波长的显著位移。因此，通过用 2-氨基乙硫醇（AET）和 PMBA 修饰的金纳米粒子（Au NPs）增强了对葡萄糖的响应。由于葡萄糖具有通过与另一组邻位二醇基团和金表面上的 PMBA 进行二次结合来捕获信号放大标签（Au NPs/AET-PMBA）的能力，因此确保了选择性。因此，形成了葡萄糖浓度依赖性的三明治结构，并且 Au NPs 与 Au 膜之间的耦合导致 SPR 共振波长的红移。实验结果表明，该 SPR 传感器对葡萄糖的响应范围在 0.01-30mM 之间优于对果糖和半乳糖的响应。定量葡萄糖的最低浓度低至 80nM，低于生理血糖水平。然后在尿样中准确检测到葡萄糖，表明该传感器在尿液中葡萄糖分析中的潜在应用。我们相信，我们提出的 PMBA 修饰的单个放大标签和传感原理也可用于由碳水化合物结构组成的生物分子，特别是用于与 DNA 相关的生物分析。
