Lanthanide coordination polymers used for fluorescent ratiometric sensing of H2O2 and glucose

Abstract

Scheme 1. Schematic description of the preparation of GOx@Tb-ATA/GDP CPs and detection of glucose. • The dual-emission multi-functional probes based on Ln CPs were facilely prepared by self-assembly. • The ratiometric fluorescence method based on double ligand Ln 3+ coordination polymers for H 2 O 2 detection was realized. • By integrating GOx through the adaptive inclusion property of CPs in the self-assembly process, a simple, highly selective and sensitive one-pot retiometric glucose assay was developed. A dual-emission lanthanide coordination polymers (Ln CPs) were facilely prepared by self-assembly of guanine diphosphate (GDP) and 2-aminoterephthalic acid (ATA) with Tb 3+ , termed as Tb-ATA/GDP CPs. GDP played as the antenna ligand to sensitize the luminescence of Tb 3+ , and ATA served as a fluorescent auxiliary ligand for the ratiometric assay. The obtained Tb-ATA/GDP CPs exhibited both blue-emission of ATA at 430 nm and characteristic green-emission of Tb 3+ under a single excitation wavelength. Upon addition of H 2 O 2 , the fluorescence of Tb 3+ could be selectively quenched and that of ATA slightly enhanced. The fluorescence intensity ratio at 430 nm and 549 nm (I 430 /I 549 ) increased linearly with increasing the concentration of H 2 O 2 in the range of 0.005–20 μM and 120–500 μM, and the detection limit was 3.42 nM. Furthermore, by integrating the glucose oxidase (GOx) through the adaptive inclusion ability of Ln CPs, GOx@Tb-ATA/GDP CPs were facilely obtained. Based on their high affinity to oxidize glucose and the fluorescence response to the generated H 2 O 2 , a simple, highly selective and sensitive one-pot ratiometric glucose assay was developed. This work will facilitate the design and construct of multi-functional fluorescent probes based on the Ln CPs, and exploit their applications in bio-sensing and environmental analysis.