Ning Keke, Fu Yao, Wu Jianghong, Sun Yujie, Liu Ke, Ye Kang, Liu Jiaxin, Wu Yuan, Liang Jiangong
College of Science, State Key Laboratory of Agricultural Microbiology, Huazhong Agricultural University, Wuhan, 430070, P. R. China.
Anal Methods. 2022 Dec 22;15(1):79-86. doi: 10.1039/d2ay01658c.
Alkaline phosphatase (ALP), one of the vital biomarkers in several diseases, plays a role in indicating disease presence or severity in early diagnosis. Here, a simple HO assisted top-down method was used to synthesize sulfur quantum dots (SQDs) with excitation and emission at 355 nm and 440 nm. Adding ALP into -nitrophenyl phosphate (-NPP) and SQDs was found to exhibit a red shift in the emission wavelength and fluorescence intensity quenching of SQDs, respectively, allowing us to propose dual-sensor platforms of red shift of emission wavelength (RSEW) and fluorescence quenching of SQDs. These dual-sensor platforms were highly sensitive and selective in ALP detection, with a linear response to ALP in the concentration range of 0.25 to 100 U L and detection limits of 0.08 and 0.10 U L, respectively. The absorption of -NP at 400 nm showed a good overlap with the excitation and emission of SQDs, leading to inner filter effect-based RSEW and fluorescence quenching of SQDs. This sensor platform was successfully applied in ALP sensing of serum samples as well as monitoring of ALP in cells. More importantly, this platform can serve as an example of using RSEW to detect ALP.
碱性磷酸酶（ALP）是多种疾病中的重要生物标志物之一，在早期诊断中对指示疾病的存在或严重程度发挥着作用。在此，采用一种简单的羟基自由基（HO）辅助自上而下法合成了激发和发射波长分别为355 nm和440 nm的硫量子点（SQDs）。发现将ALP添加到对硝基苯磷酸酯（-NPP）和SQDs中时，分别会使SQDs的发射波长发生红移和荧光强度猝灭，从而使我们能够构建发射波长红移（RSEW）和SQDs荧光猝灭的双传感器平台。这些双传感器平台在ALP检测中具有高灵敏度和选择性，对ALP在0.25至100 U/L浓度范围内呈线性响应，检测限分别为0.08和0.10 U/L。对硝基苯酚（-NP）在400 nm处的吸收与SQDs的激发和发射有良好的重叠，导致基于内滤效应的RSEW和SQDs荧光猝灭。该传感器平台成功应用于血清样品中ALP的传感以及细胞内ALP的监测。更重要的是，该平台可作为利用RSEW检测ALP的一个实例。
