Ratiometric Near-Infrared Fluorescent Probes Based on Hemicyanine Dyes Bearing Dithioacetal and Formal Residues for pH Detection in Mitochondria.

ABSTRACT: Ratiometric near-infrared fluorescent probes (AH⁺ and BH⁺) have been prepared for pH determination in mitochondria by attaching dithioacetal and formal residues onto a hemicyanine dye. The reactive formyl group on probe BH⁺ allows for retention inside mitochondria as it can react with a protein primary amine residue to form an imine under slightly basic pH 8.0. Probes AH⁺ and BH⁺ display ratiometric fluorescent responses to pH changes through the protonation and deprotonaton of a hydroxy group in hemicyanine dyes with experimentally determined pKa values of 6.85 and 6.49, respectively. Calculated pK_a values from a variety of theoretical methods indicated that the SMD_BONDI

SUBMITTER: Yan Y 

PROVIDER: S-EPMC8038704 | biostudies-literature | 2021 Apr

REPOSITORIES: biostudies-literature