Key Laboratory of Cluster Science of Ministry of Education, Beijing Institute of Technology, Beijing 100081, China.
Talanta. 2013 Jan 30;104:149-54. doi: 10.1016/j.talanta.2012.11.017. Epub 2012 Nov 21.
Rapid detection of hormones at sub-ng/ml concentrations is of tremendous importance for diagnostic purposes, quality control, and environmental monitoring. In this respect, we report a novel label-free biosensor based on hydrogel optical waveguide spectroscopy (HOWS) for the sensitive detection of 17β-estradiol (E2). This approach was implemented by using a thin hydrogel layer of a carboxylated poly(N-isoproprylacrylamide) (PNIPAAm) terpolymer that was attached to a metallic sensor surface in order to simultaneously serve as a binding matrix and an optical waveguide. Refractive index changes that are accompanied with the specific capture of biomolecules from an aqueous sample on the sensor surface were probed by resonantly excited hydrogel optical waveguide modes. To optically excite and interrogate these waves, an optical setup based on Kretschmann configuration of attenuated total reflection (ATR) method that is compatible with surface plasmon resonance (SPR) was used. We demonstrate that HOWS offers a higher binding capacity, good anti-fouling properties, improved figure of merit, and E2 detection limit of 50 pg/ml which is seven times better than that obtained by a regular surface plasmon resonance (SPR) biosensor.
快速检测亚纳克每毫升浓度的激素对于诊断、质量控制和环境监测具有重要意义。在这方面，我们报告了一种基于水凝胶光学波导光谱（HOWS）的新型无标记生物传感器，用于灵敏检测 17β-雌二醇（E2）。该方法通过使用附着在金属传感器表面上的薄羧基化聚（N-异丙基丙烯酰胺）（PNIPAAm）三聚物水凝胶层来实现，该水凝胶层同时用作结合基质和光学波导。通过共振激发水凝胶光学波导模式来探测伴随传感器表面上特定捕获生物分子的折射率变化。为了光学激发和询问这些波，使用了与表面等离子体共振（SPR）兼容的基于衰减全反射（ATR）方法的 Kretschmann 配置的光学设置。我们证明 HOWS 提供了更高的结合容量、良好的抗污染性能、改进的品质因数和 50pg/ml 的 E2 检测限，比常规的表面等离子体共振（SPR）生物传感器的检测限提高了 7 倍。
