An Aggregation‐Induced Emission Active Peptide‐Based Fluorescent Probe for Highly Selective and Sensitive Detection of Hg(II) Ions and Its Multifield Applications
Shiyi Xiong, Xinlin Cao, Mengying Jia, Yi Ren, Peng Wang
Abstract
ABSTRACT In this study, a novel aggregation‐induced emission (AIE) active peptide‐based fluorescent probe ( L ) was rationally designed and successfully synthesized with a tetraphenylethene (TPE) derivative modified tetrapeptide (Pro–Gly–Asp–His–NH 2 ). L has many advantages of good water solubility, a large Stokes shift, and a high fluorescence quantum yield. According to the design, L was utilized to selectively recognize Hg 2+ against other competitive metal ions in the HEPES buffer solution (pH = 7.4, 10.0 mM, containing 5% DMSO), and the limit of detection (LOD) for Hg 2+ was obtained to be as low as 25.4 nM. In addition, L not only was successfully applied to monitor Hg 2+ in living cells and zebrafish larvae, but also was used to measure Hg 2+ in three different real water samples. Moreover, the test strips were successfully made using L solution, and qualitatively identified Hg 2+ through using the naked eye under UV light at 365 nm. Furthermore, the reversible switching characteristics of L were used to mimic the INHIBIT molecular logic gate. More interestingly, the integrated smartphone color recognition App converts the color of L solution into digital values through the RGB channel and was successfully applied to the semiquantitative detection of Hg 2+ without relying on expensive instruments.