A terbium chelate based fluorescent assay for alkaline phosphatase in biological fluid

作者:Ma, Chanjiao; Tan, Hongliang*; Chen, Lili; Song, Yonghai; Xu, Fugang; Chen, Shouhui; Wang, Li
来源:Sensors and Actuators B: Chemical , 2014, 202: 683-689.
DOI:10.1016/j.snb.2014.06.007

摘要

Determination of alkaline phosphatase (ALP) is of great importance because of its crucial roles in biomedical research and clinical diagnosis. In this work, a simple and sensitive fluorescent assay of studying dephosphorylation behavior of alkaline phosphatase (ALP) was developed by employing a terbium-guanosine monophosphate (Tb-GMP) chelate as fluorescent probe and calf intestine alkaline phosphatase (CIAP) as a model system. The removal of phosphate group from GMP by the hydrolysis of CIAP leads to the decrease in the fluorescence of Tb-GMP chelate. As a fluorescent probe for CIAP, Tb-GMP chelate exhibits excellent selectivity and high sensitivity up to 0.001 U/L detection limit. Compared with other methods for the detection of ALP including CIAP, the Tb-GMP chelate probe not only has a simpler preparation procedure, but also possesses a long enough fluorescence lifetime for time-resolved fluorescent assays. The Tb-GMP chelate probe was also successfully applied to determine the CIAP in serum samples and showed a satisfactory result. Taking into account the advantages of natural biomolecule as substrate and long emission lifetime of Tb-GMP chelate, the proposed method was expected to have potential for assessing ALP in biological system and clinical samples.