Related Experiment Video
Updated: Feb 3, 2026

Magnetic Resonance Spectroscopy of live Drosophila melanogaster using Magic Angle Spinning
Published on: April 15, 2010
Toward Magic Photoacids: Proton Transfer in Concentrated Sulfuric Acid
Daniel Maus1, Alexander Grandjean1, Gregor Jung1
1Biophysical Chemistry , Saarland University , Campus B2 2, 66123 Saarbruecken , Germany.
Abstract:
Photoacids are the most convenient way to deliver protons on demand. So far, their photoacidity allows for studying excited-state proton transfer (ESPT) only to protic or strongly basic solvent molecules. The strongest superphotoacids known so far exhibit excited-state lifetimes of their conjugate base on the order of 100 ps before recapturing the proton again. Here, we describe how we developed a new aminopyrene-based superphotoacid with an excited-state lifetime of its conjugate base of several nanoseconds. It will be shown by fluorescence titration and via Förster cycle that the excited-state acidity is as high as concentrated sulfuric acid and thus exceeding any previous photoacidity by several orders of magnitude. Its outstanding chemical stability and fluorescent properties make it suitable for time-resolved proton-transfer studies in concentrated mineral acids and organic solvents of low basicity.
Related Concept Videos
The Sulfur Cycle
Titration of a Polyprotic Acid
Polyprotic Acids
Amino acids
Acids, Bases and Neutralization Reactions
Magical Thinking

