A highly sensitive fluorescent acidic pH probe based on rhodamine B diethyl-2-aminobutenedioate conjugate and its application in living cells

摘要

A highly sensitive fluorescent acidic pH probe based on rhodamine B-2-aminobutenedioate conjugate, was designed and synthesized. When the H~+ concentration falls within the pH range of 4.0-6.5, the spirolactam unit of rhodamine B-2-aminobutenedioate was opened, which resulted in the dramatic enhancement of both fluorescence and absorbance intensity as well as the color change of the solution. Background metal ions showed small or no interference with the detection of H~+. Confocal laser scanning microscopy experiments showed that rhodamine B-2-aminobutenedioate can be applied to detect acidic pH variations in living cells with a turn-on signal.