State Key Laboratory of Medicinal Chemical Biology, College of Pharmacy, College of Chemistry, Research Center for Analytical Sciences, and Tianjin Key Laboratory of Molecular Recognition and Biosensing, Nankai University , Tianjin 300071, China.
Collaborative Innovation Center of Chemical Science and Engineering (Tianjin) , Tianjin 300071, China.
Anal Chem. 2017 Feb 7;89(3):1551-1557. doi: 10.1021/acs.analchem.6b03521. Epub 2017 Jan 20.
We report a surprising discovery that Prussian blue (PB) can be employed as a highly sensitive and background-free resonant Raman reporter. Conventional Raman reporters show multiple spectral bands in the fingerprint region, which are generally overlapped with those from dominant endogenous biomolecules, and are thus difficult to be separated. Herein, we found that PB only possesses a strong and sharp single-band in the cellular Raman-silent region, where no Raman signals from biological species were observed. Therefore, the Raman spectra from PB and endogenous biomolecules are completely resolved without resorting to complicated spectral unmixing. Moreover, PB holds a strong UV-vis absorption band between 500 and 900 nm, which is resonant with the incident detection lasers, providing extremely high sensitivity. Through assembly of PB onto plasmonic cores, a new surface-enhanced resonance Raman scattering (SERRS) probe was achieved with a high signal-to-background ratio (SBR). We demonstrated the performance of the PB-based SERRS tags for high-sensitivity immunoassay and cancer cell imaging.
我们报告了一个惊人的发现，普鲁士蓝（PB）可用作高度灵敏且无背景的共振拉曼报告物。传统的拉曼报告物在指纹区域显示出多个光谱带，这些光谱带通常与主要的内源性生物分子的光谱带重叠，因此难以分离。在这里，我们发现 PB 仅在细胞拉曼静默区域具有强而尖锐的单带，在该区域中没有观察到来自生物物种的拉曼信号。因此，无需使用复杂的光谱解混，就可以完全分辨出 PB 和内源性生物分子的拉曼光谱。此外，PB 在 500 到 900nm 之间具有强的紫外可见吸收带，与入射检测激光共振，从而提供了极高的灵敏度。通过将 PB 组装到等离子体核上，实现了具有高信噪比（SBR）的新型表面增强共振拉曼散射（SERRS）探针。我们展示了基于 PB 的 SERRS 标签在高灵敏度免疫测定和癌细胞成像中的性能。
