Department of Hepatobiliary and Pancreatic Surgery, the First Affiliated Hospital of Zhengzhou University , Zhengzhou 450001, China.
Institute of Interdisciplinary Medicine, Shanghai University of Traditional Chinese Medicine , Shanghai, 201213, China.
Anal Chem. 2017 Sep 19;89(18):9884-9891. doi: 10.1021/acs.analchem.7b01975. Epub 2017 Aug 30.
In this study, a novel fluorescent detection system for biological sensing of human albumin (HA) was developed on the basis of the pseudoesterase activity and substrate preference of HA. The designed near-infrared (NIR) fluorescent probe (DDAP) could be effectively hydrolyzed by HA, accompanied by significant changes in both color and fluorescence spectrum. The sensing mechanism was fully investigated by fluorescence spectroscopy, NMR, and mass spectra. DDAP exhibited excellent selectivity and sensitivity toward HA over a variety of human plasma proteins, hydrolases, and abundant biomolecules found in human body. The probe has been successfully applied to measure native HA in diluted plasma samples and the secreted HA in the hepatocyte culture supernatant. DDAP has also been used for fluorescence imaging of HA reabsorption in living renal cells, and the results show that the probe exhibits good cell permeability, low cytotoxicity and high imaging resolution. Furthermore, DDAP has been successfully used for real-time tracking the uptaking and degradation of albumin in ex vivo mouse kidney models for the first time. All these results clearly demonstrated that DDAP-based assay held great promise for real-time sensing and tracking HA in complex biological systems, which would be very useful for basic researches and clinical diagnosis of HA-associated diseases.
在这项研究中，基于人血清白蛋白（HA）的拟酯酶活性和底物偏好性，开发了一种用于生物传感的新型荧光检测系统。所设计的近红外（NIR）荧光探针（DDAP）可被 HA 有效水解，同时伴随颜色和荧光光谱的显著变化。通过荧光光谱、NMR 和质谱对传感机制进行了充分研究。DDAP 对 HA 表现出优异的选择性和灵敏度，可区分多种人血浆蛋白、水解酶和人体中丰富的生物分子。该探针已成功应用于测定稀释血浆样品中的天然 HA 和肝细胞培养上清液中分泌的 HA。DDAP 还用于活肾细胞中 HA 重吸收的荧光成像，结果表明该探针具有良好的细胞通透性、低细胞毒性和高成像分辨率。此外，DDAP 还首次成功用于实时跟踪在体小鼠肾脏模型中白蛋白的摄取和降解。所有这些结果清楚地表明，基于 DDAP 的测定方法在复杂的生物体系中对 HA 的实时传感和跟踪具有广阔的应用前景，这对于 HA 相关疾病的基础研究和临床诊断将非常有用。
