A new, general method for the determination of binding constants: photoacoustic titration of dansylamide with carbonic anhydrase

We have developed a new method utilizing the partitioning of energy between radiative and non-radiative pathways following photostimulation for the determination of binding constants in biochemical systems; application of this photoacoustic calorimetry technique to the study of the inhibition of carbonic anhydrase by 1-(dimethylamino)-5-naphthalenesulphonamide yields K11= 1.7 (±0.4)× 106 mol–1 dm3.