Immobilization of Quantum Dots in Nanostructured Porous Silicon Films: Characterizations and Signal Amplification for Dual-Mode Optical Biosensing
Immobilization of Quantum Dots in Nanostructured Porous Silicon Films: Characterizations and Signal Amplification for Dual-Mode Optical Biosensing
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DOI：
10.1002/adfm.201202697
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发表时间：
2013-08-07
影响因子：
19
通讯作者：
Weiss, Sharon M.
中科院分区：
文献类型：
--
作者：
Gaur, Girija;Koktysh, Dmitry S.;Weiss, Sharon M.
高灵敏度的双模标记检测生物素的多孔硅（PSi）薄膜，使用胶体量子点（QD）作为信号放大器的证明。通过表征和调整孔隙率、膜深度和孔径来进行用于靶向QD渗透和固定的PSi平台的优化。通过反射干涉光谱法和荧光测量来监测目标QD-生物素缀合物与固定在孔壁上的链霉亲和素探针的结合事件。目标生物素分子的QD标记使得能够基于不同的荧光信号进行检测，以及测量的光谱反射率条纹偏移的大于5倍的增强和多孔基质内仅6%表面积覆盖的QD的检测限的近三个数量级的改善。利用QD信号放大器，一个特殊的生物素检测限约为6 fg mm（-2）的证明与子fg mm（-2）的检测限可实现。
Highly sensitive dual-mode labeled detection of biotin in well-characterized porous silicon (PSi) films using colloidal quantum dots (QDs) as signal amplifiers are demonstrated. Optimization of the PSi platform for targeted QD infiltration and immobilization is carried out by characterizing and tuning the porosity, film depth, and pore size. Binding events of target QD-biotin conjugates with streptavidin probes immobilized on the pore walls are monitored by reflective interferometric spectroscopy and fluorescence measurements. QD labeling of the target biotin molecules enables detection based on a distinct fluorescent signal as well as a greater than 5-fold enhancement in the measured spectral reflectance fringe shift and a nearly three order of magnitude improvement in the detection limit for only 6% surface area coverage of QDs inside the porous matrix. Utilizing the QD signal amplifiers, an exceptional biotin detection limit of approximate to 6 fg mm(-2) is demonstrated with sub-fg mm(-2) detection limits achievable.