The Marriage of Protein and Lanthanide: Unveiling a Time-Resolved Fluorescence Sensor Array Regulated by pH toward High-Throughput Assay of Metal Ions in Biofluids

Abstract

A protein/lanthanide complex (BSA/Tb 3+ )-based sensor array in two different pH buffers has been designed for high-throughput recognition and time-resolved fluorescence (TRF) detection of metal ions in biofluids. BSA, which acted as an antenna ligand, can sensitize the fluorescence of Tb 3+ (i.e., antenna effect), while the presence of metal ions would lead to the corresponding conformational change of BSA for altering the antenna effect accompanied by a substantial TRF performance of Tb 3+ . This principle has also been fully proved by both experimental characterizations and coarse-grained molecular dynamics (CG-MD) studies. By using Tris-HCl buffer with different pHs (at 7.4 and 8.5), 17 metal ions have been welldistinguished by using our proposed BSA/Tb 3+ sensor array. Moreover, the sensor array has the potential to discriminate different concentrations of the same metal ions and a mixture of metal ions. Remarkably, the detection of metal ions in biofluids can be realized by utilizing the presented sensor array, verifying its practical applications. The platform avoids the synthesis of multiplex sensing receptors, providing a new method for the construction of convenient and feasible lanthanide complex-based TRF sensing arrays.

Luminescent lanthanide complexes for reactive oxygen species biosensing and possible application in Alzheimer’s diseases

“…Protein can also serve as a ligand for lanthanide ion and act as an antenna to sensitize the lanthanide via energy transfer. This has recently been shown by Lin et al with Bovine Serum Albumin and Tb(III) [119]. BSA was found to bind 69Tb(III) ions without detectable conformational change.…”

“…This has recently been shown by Lin et al . with Bovine Serum Albumin and Tb(III) [119]. BSA was found to bind 69Tb(III) ions without detectable conformational change.…”

Luminescent Lifetime Regulation of Lanthanide-Doped Nanoparticles for Biosensing

“…A 2000 μs gate time and a 50 μs delay time were settled for time-resolved fluorescence spectra by recording at 548 nm. Furthermore, the sensing platform could distinguish the various concentrations of the identical metal ions and the variety of metal ions mixture, even in biofluids [ 70 ]. Nagano et al designed luminescent Eu 3+ complexes (Eu-7) for time-resolved, long-lived luminescence microscopy (TRLLM).…”

Tb(iii)-doped nanosheets as a fluorescent probe for the detection of dipicolinic acid

“…According to Scheme 1, aer coordination with the trivalent terbium ion, DPA can sensitize Tb(III) upon excitation by ultraviolet (UV) light, and the uorescence intensity is greatly increased by the absorption-energy transfer-emission process. [20][21][22] Based on the above characteristics, the use of the Tb(III) ion has become one of the most popular approaches to detect DPA, with extremely high sensitivity as well as accurate and reliable detection results. 11 Nano-structured materials have special surface and interface effects and are advantageous because of their small size, and therefore, they are excellent candidates for the preparation of biochemical probes.…”