Yongsheng Lei, Yannan Xiao, Lin Yuan, Chen Ma, Haibo Yu, Ying Zhang

School of Environment, Liaoning University

Xinfu Zhang, Yi Xiao

Dalian University of Technology

Abstract

Different from five-membered rhodamine spirolactam (Rh-OH), a new six-membered spiro-rhodamine probe (SRh-OH) bearing urea structure has been developed in this paper. Compared with fivemembered Rh-OH, six-membered SRh-OH exhibited higher selectivity and sensitivity to Cu²⁺ in aqueous solution. Upon addition of 10 equiv. Cu²⁺, the molar extinction coefficient of SRh-OH at 563 nm can be up to 4.73 * 10⁴ Lmol^-1 cm^-1. In the range of Cu²⁺ from 0 to 28 μM, there was an excellent linear relationship between the absorption or emission intensity and Cu²⁺ concentration. The detection limit of SRh-OH was as low as 26 nM (S/N = 3). The reversible binding mode of SRh-OH with Cu²⁺ was further confirmed by S2^- and EDTA addition. Bio-imaging showed SRh-OH can map the distribution of Cu²⁺ not only in mitochondria but also in lysosomes of Hela cells.

Read the article here:   6-A new six-membered spiro-rhodamine probe for Cu2+ and its imaging in mitochondria and lysosomes of Hela cells.pdf