Benefit from the additional correction of the output signal in dual-mode detection, traditional dual signal readout strategies are performed by constructing the ratiometric fluorescent probe through excitation energy transfer (EET) or fluorescence resonance energy transfer (FRET). To avoid the complicated modification process and obtain the results rapidly, a simple dual-mode sensing strategy based on the electronic effects of p-nitrophenol (PNP) is described to monitor the activities of alkaline phosphatase (ALP). In the sensing platform, p-nitrophenylphosphate was used as a substrate to produce the PNP using ALP as the catalyst. Due to the PNP possesses negative effect of induction and conjugation, photoinduced electron transfer and hyperchromic effect have been achieved between PNP and polyethyleneimine-protected copper nanoclusters (PEI-Cu NCs), which caused the changes of the fluorescence intensity and UV-visible absorption. The dual-mode signal sensing system showed the satisfactory linear results of ALP from 1 to 100 U/L for fluorescent sensing strategy and 1-70 U/L for the absorption method with a competitive LOD of 0.27 and 0.87 U/L (signal-to-noise ratio of 3). This strategy detected biological ALP in human serum and bio-imaging of endogenous ALP in A549 cells successfully, which verifies a certain potential of the strategy for the practical applications.

中文翻译：

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基于光诱导电子转移和增色效应的内源性碱性磷酸酶传感和生物成像双模策略

受益于双模式检测中输出信号的额外校正，传统的双信号读出策略是通过激发能量转移 (EET) 或荧光共振能量转移 (FRET) 构建比率荧光探针来执行的。为了避免复杂的修饰过程并快速获得结果，描述了一种基于对硝基苯酚（PNP）电子效应的简单双模传感策略来监测碱性磷酸酶（ALP）的活性。在传感平台中，对硝基苯磷酸盐用作底物，以 ALP 为催化剂生产 PNP。由于 PNP 具有诱导和共轭的负面作用，PNP和聚乙烯亚胺保护的铜纳米团簇（PEI-Cu NCs）之间实现了光致电子转移和增色效应，引起了荧光强度和紫外可见吸收的变化。双模信号传感系统显示出令人满意的线性结果，荧光传感策略的 ALP 为 1 至 100 U/L，吸收方法的 ALP 线性结果为 1-70 U/L，具有竞争力的 LOD 为 0.27 和 0.87 U/L（信号- 3）的信噪比。该策略成功检测了人血清中的生物ALP，并成功实现了A549细胞内源性ALP的生物成像，验证了该策略具有一定的实际应用潜力。双模信号传感系统显示出令人满意的线性结果，荧光传感策略的 ALP 为 1 至 100 U/L，吸收方法的 ALP 线性结果为 1-70 U/L，具有竞争力的 LOD 为 0.27 和 0.87 U/L（信号- 3）的信噪比。该策略成功检测了人血清中的生物ALP，并成功实现了A549细胞内源性ALP的生物成像，验证了该策略具有一定的实际应用潜力。双模信号传感系统显示出令人满意的线性结果，荧光传感策略的 ALP 为 1 至 100 U/L，吸收方法的 ALP 线性结果为 1-70 U/L，具有竞争力的 LOD 为 0.27 和 0.87 U/L（信号- 3）的信噪比。该策略成功检测了人血清中的生物ALP，并成功实现了A549细胞内源性ALP的生物成像，验证了该策略具有一定的实际应用潜力。