Using LysoSensor Yellow/Blue DND-160 to sense acidic pH under high hydrostatic pressures.
LysoSensor Yellow/Blue DND-160, a dual-wavelength fluorophore commonly used for sensing pH in acidic organelles, possesses solvatochromic behavior believed to originate from an intramolecular charge transfer (ICT). Given this, we investigated whether DND-160 can be used for acidic pH sensing under hydrostatic pressures up to 510 atm, a range suitable for studying a wide variety of cellular processes. We found that the emission spectrum of the protonated form does not exhibit sensitivity to pressure, whereas the deprotonated form shows a piezochromic shift consistent with increased ICT character. Although pressure effects on the apparent pKa are buffer solvent dependent, DND-160 retains two-state behavior, making it a useful acidic pH probe under pressure.
DePedro
Hector Michael
HM
Department of Physics, Miami University, Oxford, OH 45056, USA.
Urayama
Paul
P
D005456:Fluorescent Dyes / Q000737:chemistry*; D006863:Hydrogen-Ion Concentration; D006874:Hydrostatic Pressure; D007700:Kinetics; D010080:Oxazoles / Q000737:chemistry*
C120434:2-(4-pyridyl)-5-((4-(2-dimethylaminoethylaminocarbamoyl)methoxy)phenyl)oxazole; D005456:Fluorescent Dyes; D010080:Oxazoles