Combined enhanced fluorescence and label-free biomolecular detection with a photonic crystal surface
Combined enhanced fluorescence and label-free biomolecular detection with a photonic crystal surface
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DOI：
10.1364/ao.46.002351
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发表时间：
2007-04-20
期刊：
影响因子：
1.9
通讯作者：
Cunningham, Brian T.
中科院分区：
文献类型：
--
作者：
Mathias, Patrick C.;Ganesh, Nikhil;Cunningham, Brian T.
二维光子晶体表面具有不同的周期在每个横向方向被证明检测生物分子使用两种不同的传感模式。传感机制都依赖于在两个特定波长之一产生共振反射峰，这取决于入射到光子晶体上的光的偏振。一种偏振在可见光谱中产生共振反射峰，与荧光团的激发波长一致，而正交偏振在红外波长处产生共振反射峰，用于吸附生物分子的无标记检测。用于荧光激发的光子晶体共振使结构表面的近场增强，导致距离器件表面100 nm范围内的荧光团信号增加。用白光照射光子晶体，利用高分辨率成像检测仪器监测红外共振峰反射波长的位移，实现无标签检测。采用严格的耦合波分析来确定光子晶体结构的最佳尺寸，并采用基于聚合物的纳米复制成型方法制造器件。利用染料共轭链霉亲和素的斑点阵列证明了基于荧光和无标记的检测。荧光信号的定量分析表明，光子晶体上蛋白质斑点的荧光输出增加了35倍，并且沉积的斑点也可以在无标记检测模式下成像。(c) 2007年美国光学学会。
A 2D photonic crystal surface with a different period in each lateral direction is demonstrated to detect biomolecules using two distinct sensing modalities. The sensing mechanisms both rely on the generation of a resonant reflection peak at one of two specific wavelengths, depending on the polarization of light that is incident on the photonic crystal. One polarization results in a resonant reflection peak in the visible spectrum to coincide with the excitation wavelength of a fluorophore, while the orthogonal polarization results in a resonant reflection peak at an infrared wavelength which is used for label-free detection of adsorbed biomolecules. The photonic crystal resonance for fluorescence excitation causes enhanced near fields at the structure surface, resulting in increased signal from fluorophores within 100 nm of the device surface. Label-free detection is performed by illuminating the photonic crystal with white light and monitoring shifts in the peak reflected wavelength of the infrared resonance with a high-resolution imaging detection instrument. Rigorous coupled-wave analysis was used to determine optimal dimensions for the photonic crystal structure, and devices were fabricated using a polymer-based nanoreplica molding approach. Fluorescence-based and label-free detection were demonstrated using arrays of spots of dye-conjugated streptavidin. Quantification of the fluorescent signal showed that the fluorescence output from protein spots on the photonic crystal was increased by up to a factor of 35, and deposited spots were also imaged in the label-free detection mode. (c) 2007 Optical Society of America.