Benzimidazole-Based Ratiometric Two-Photon Fluorescent Probes for Acidic pH in Live Cells and Tissues
摘要:
Many aspects of cell metabolism are controlled by acidic pH. We report a new family of small molecule and ratiometric two photon (TP) probes derived from benzimidazole (BH1-3 and BH1L) for monitoring acidic pH values. These probes are characterized by a strong two-photon excited fluorescence, a marked blue-to-green emission color change in response to pH, pK(a) values ranging from 4.9 to 6.1, a distinctive isoemissive point, negligible cytotoxicity, and high photostability, thereby allowing quantitative analysis of acidic pH. Moreover, we show that BH1L optimized as a lysosomal-targeted probe allows for direct, real-time estimation of the pH values inside lysosomal compartments in live cells as well as in living mouse brain tissues through the use of two-photon microscopy. These findings demonstrate that these probes will find useful applications in biomedical research.
Method for imaging zinc activation within a mitochondrion using a two-photon fluorescent probe, and method for manufacturing the two-photon fluorescent probe
A Mitochondrial-Targeted Two-Photon Probe for Zinc Ion
作者:Goutam Masanta、Chang Su Lim、Hyung Joong Kim、Ji Hee Han、Hwan Myung Kim、Bong Rae Cho
DOI:10.1021/ja200444t
日期:2011.4.20
We report a two-photon probe (SZn-Mito) for mitochondrial zinc ions ([Zn2+](m)). This probe shows a 7-fold enhancement of two-photon-excited fluorescence in response to Zn2+ with a dissociation constant (K-d(TP)) of 3.1 +/- 0.1 nM and pH insensitivity in the biologically relevant range, allowing the detection of [Zn2+](m) in a rat hippocampal slice at a depth of 100-200 mu m without interference from other metal ions through the use of two-photon microscopy.