Department of Chemistry, University of British Columbia, Vancouver, BC V6T 1Z1, Canada.
Appl Spectrosc. 2013 Mar;67(3):215-52. doi: 10.1366/12-06948.
Semiconductor quantum dots (QDs) are brightly luminescent nanoparticles that have found numerous applications in bioanalysis and bioimaging. In this review, we highlight recent developments in these areas in the context of specific methods for fluorescence spectroscopy and imaging. Following a primer on the structure, properties, and biofunctionalization of QDs, we describe select examples of how QDs have been used in combination with steady-state or time-resolved spectroscopic techniques to develop a variety of assays, bioprobes, and biosensors that function via changes in QD photoluminescence intensity, polarization, or lifetime. Some special attention is paid to the use of Förster resonance energy transfer-type methods in bioanalysis, including those based on bioluminescence and chemiluminescence. Direct chemiluminescence, electrochemiluminescence, and charge transfer quenching are similarly discussed. We further describe the combination of QDs and flow cytometry, including traditional cellular analyses and spectrally encoded barcode-based assay technologies, before turning our attention to enhanced fluorescence techniques based on photonic crystals or plasmon coupling. Finally, we survey the use of QDs across different platforms for biological fluorescence imaging, including epifluorescence, confocal, and two-photon excitation microscopy; single particle tracking and fluorescence correlation spectroscopy; super-resolution imaging; near-field scanning optical microscopy; and fluorescence lifetime imaging microscopy. In each of the above-mentioned platforms, QDs provide the brightness needed for highly sensitive detection, the photostability needed for tracking dynamic processes, or the multiplexing capacity needed to elucidate complex systems. There is a clear synergy between advances in QD materials and spectroscopy and imaging techniques, as both must be applied in concert to achieve their full potential.
半导体量子点（QDs）是一种明亮发光的纳米颗粒，在生物分析和生物成像领域有广泛的应用。在这篇综述中，我们重点介绍了这些领域的最新进展，特别是针对荧光光谱和成像的特定方法。在介绍了 QD 的结构、性质和生物功能化之后，我们描述了一些选择的例子，说明了 QD 如何与稳态或时间分辨光谱技术结合使用，开发了各种通过改变 QD 光致发光强度、偏振或寿命来实现的分析物检测、生物探针和生物传感器。特别关注了生物分析中基于Förster 共振能量转移（FRET）类型的方法，包括基于生物发光和化学发光的方法。同样讨论了直接化学发光、电化学发光和电荷转移猝灭。我们进一步描述了 QD 与流动细胞术的结合，包括传统的细胞分析和基于光谱编码条码的分析技术，然后将注意力转向基于光子晶体或等离子体耦合的增强荧光技术。最后，我们调查了 QD 在不同平台上的生物荧光成像应用，包括明场荧光、共聚焦和双光子激发显微镜；单颗粒跟踪和荧光相关光谱；超分辨率成像；近场扫描光学显微镜；和荧光寿命成像显微镜。在上述所有平台中，QD 提供了高灵敏度检测所需的亮度、跟踪动态过程所需的光稳定性，或者阐明复杂系统所需的多路复用能力。QD 材料和光谱学与成像技术的进步之间存在明显的协同作用，因为要充分发挥它们的潜力，两者必须协同应用。
