Research Center for Analytical Sciences , College of Chemistry , Tianjin Key Laboratory of Biosensing and Molecular Recognition , and State Key Laboratory of Medicinal Chemical Biology , Nankai University , Tianjin 300071 , China.
Collaborative Innovation Center of Chemical Science and Engineering (Tianjin) , Tianjin 300071 , China.
ACS Sens. 2018 Sep 28;3(9):1846-1854. doi: 10.1021/acssensors.8b00680. Epub 2018 Sep 18.
Traditional photoluminescence resonance energy transfer (PRET)-based sensors are widely applied, but still suffer from the severe background interference from in situ excitation. The afterglow nature of the persistent luminescence nanoparticles (PLNPs) allows optosensing after the stoppage of in situ illumination, and thus subtly overcomes that interference. We proposed a simple strategy for functionalizing PLNPs for bioanalytical applications and the new afterglow resonance energy transfer (ARET)-based assay for quantitative determination and imaging of fibroblast activation protein-alpha (FAPα) in live cells using Au-decorated Cr:ZnGaO as donor and Cy5.5-KGPNQC-SH as acceptor. The ARET between the donor and acceptor quenches the afterglow of the donor, and the cleavage of peptide KGPNQC by FAPα inhibits the ARET and restores the afterglow of the donor. The ARET-based assay of FAPα, with the linear range of 0.1-2.0 mg·L (1.2-22.9 nM), LOD of 11 μg·L (115 pM), and RSD of 3.9% (for 0.5 mg·L FAPα, n = 5), displays higher sensitivity, lower limit of detection (LOD), and better anti-interference capability than the corresponding PRET-based assay. Besides, the ARET-based sensors are lighted up by the FAPα-positive U87MG and MDA-MB-435 cells, but kept in the dark when incubated in the FAPα-negative AD293 cells. The proposed ARET-based sensor can detect FAPα of U87MG and MDA-MB-435 living cells in human serum with the spiked recoveries of 95.6-103%. Our data demonstrated a simple and effective strategy for bridging PLNPs to bioanalytical applications, and an attractive ARET assay of FAPα.
传统的光致发光共振能量转移（PRET）传感器应用广泛，但仍受到原位激发的严重背景干扰。持久发光纳米粒子（PLNPs）的余晖性质允许在原位照明停止后进行光学传感，从而巧妙地克服了这种干扰。我们提出了一种简单的策略，用于功能化 PLNPs 以用于生物分析应用，以及新的余晖共振能量转移（ARET）基础分析，用于定量测定和成像活细胞中的成纤维细胞激活蛋白-α（FAPα），使用 Au 修饰的 Cr:ZnGaO 作为供体和 Cy5.5-KGPNQC-SH 作为受体。供体和受体之间的 ARET 猝灭了供体的余晖，而 FAPα 对肽 KGPNQC 的切割抑制了 ARET 并恢复了供体的余晖。基于 ARET 的 FAPα 分析，线性范围为 0.1-2.0mg·L（1.2-22.9nM），LOD 为 11μg·L（115pM），RSD 为 3.9%（对于 0.5mg·L FAPα，n=5），显示出比相应的 PRET 基础分析更高的灵敏度、更低的检测限（LOD）和更好的抗干扰能力。此外，基于 ARET 的传感器在 FAPα 阳性的 U87MG 和 MDA-MB-435 细胞中被点亮，但在 FAPα 阴性的 AD293 细胞中保持黑暗。该方法可检测人血清中 U87MG 和 MDA-MB-435 活细胞中的 FAPα，加标回收率为 95.6-103%。我们的数据证明了一种将 PLNPs 桥接到生物分析应用的简单而有效的策略，以及一种有吸引力的 FAPα ARET 分析。
