A novel thiophene functionalized silicon-cored compounds: Aggregation-induced emission enhancement and aqueous fluorogenic Fe3+ probes in bovine serum albumin

"Silicon-cored" compounds are well known for their high value glass transition temperature, high thermal stability and excellent optical properties, but the excellent optical properties was not used for fluorogenic probes especially for Fe3+ probe. In this paper, a novel Fe3+ probe based on thiophene functionalized silane, namely, bis[3,4-dipheny1-2,5-di(2-Thienyl)phenyl]methylphenylsilane (MPS) was designed and synthesized. MPS exhibits aggregation-induced emission enhancement (AIEE) property in water/tetrahydrofuran mixtures because of restricted intramolecular rotation. The abnormal optical properties enable MPS to detect Fe3+ in aqueous-based solutions. The binding behavior of MPS aggregates to Fe3+ and other transition metal ions were studied through UV-vis, fluorescence spectroscopy, and scanning electron microscopy. Exceptional fluorescence quenching of MPS occurred during Fe3+ binding. The calculated detection limit was at ppb level, and the complex ratio of MPS to Fe3+ is approximately 1:1. MPS has both exemplary activity and high selectivity toward Fe3+ even in the presence of other metal ions. The test conditions were also expanded from water to bovine serum albumin and solid films. This study was an advancement for the application of "silicon-cored" compounds and provides guidance for using simple, low-cost, and high-selectivity Fe3+ probes in aqueous solutions and in clinical applications. (C) 2016 Elsevier B.V. All rights reserved.