β-Galactosidase Fluorescence Probe with Improved Cellular Accumulation Based on a Spirocyclized Rhodol Scaffold
摘要:
We identified a rhodol bearing a hydroxymethyl group (HMDER) as a suitable scaffold for designing fluorescence probes for various hydrolases. HMDER shows strong fluorescence at physiological pH, but phenolic O-alkylation of HMDER results in a strong preference for the spirocyclic form, which has weak fluorescence. As a proof of concept, we utilized this finding to develop a new fluorescence probe for beta-galactosidase. This probe has favorable characteristics for imaging in biological samples: it has good cellular permeability, and its hydrolysis product is well-retained intracellularly. It could rapidly and clearly visualize beta-galactosidase activity in cultured cells and in Drosophila melanogaster tissue, which has rarely been achieved with previously reported fluorescence probes.
The invention provides fluorescent sensors for the selective detection of a metal such as copper. The sensors may be considered to be derivatives of cyanine, fluorescein, rhodamine, rhodol, Tokyo green, or BODIPY. The sensors find particular use in detecting copper in cells and living animals.