Key Laboratory for Special Functional Materials of Ministry of Education, Henan University, Kaifeng 475004, PR China.
Biosens Bioelectron. 2013 Dec 15;50:137-42. doi: 10.1016/j.bios.2013.06.023. Epub 2013 Jun 18.
In this paper, we focused on the large-scale fabrication of gold nanoholes array capable of supporting surface plasmonic resonance (SPR) via the developed nanosphere lithography (NSL) technique, which could be used as high performance biosensor for the detection of specific streptavidin-biotin interactions. Direct UV-vis absorption mode measurement was used to monitor the SPR peak shift. For the better immobilization of biotin, the surface of gold nanoholes array was functionalized with 3-mercaptopropyl trimethoxysilane (MPTS) and 3-aminopropyl triethoxysilane (APTES). After the streptavidin binding to the biotin, the SPR peak position showed an 11 nm wavelength shift due to the refractive index change caused by the biotin-streptavidin binding. The sealing treatment was performed by using bovine serum albumin (BSA) to eliminate the influences of nonspecific adsorption for more accurate detection. Interestingly, the detection sensitivity of the gold nanoholes array could be further enhanced by coupling the water-soluble CdSe/ZnS quantum dots (QDs), which showed four-fold improvement in detection sensitivity as compared to the gold nanoholes array biosensor without the coupling of QDs. The mechanisms for the enhancement of detection sensitivity were also discussed. This would provide new capabilities for the highly sensitive measurements of biomolecular binding.
本文聚焦于通过开发的纳米球光刻（NSL）技术大规模制备能够支持表面等离子体共振（SPR）的金纳米孔阵列，该技术可作为用于检测特定链霉亲和素-生物素相互作用的高性能生物传感器。直接紫外-可见吸收模式测量用于监测 SPR 峰的移动。为了更好地固定生物素，金纳米孔阵列的表面用 3-巯丙基三甲氧基硅烷（MPTS）和 3-氨丙基三乙氧基硅烷（APTES）进行功能化。链霉亲和素与生物素结合后，由于生物素-链霉亲和素结合引起的折射率变化，SPR 峰位置出现了 11nm 的波长移动。通过使用牛血清白蛋白（BSA）进行密封处理，消除非特异性吸附的影响，以实现更准确的检测。有趣的是，通过耦合水溶性 CdSe/ZnS 量子点（QDs）可以进一步提高金纳米孔阵列的检测灵敏度，与未耦合 QDs 的金纳米孔阵列生物传感器相比，检测灵敏度提高了四倍。还讨论了提高检测灵敏度的机制。这将为生物分子结合的高灵敏度测量提供新的能力。
