Although we did not perform the Bathochromic titration experiments by varying salt concentration, we cite two previous observations that support that the basic deprotonation behavior of carboxylic acid remains preserved even at high salt concentration. One of those observations pertain to the interaction of oil droplets (containing dodecanoic acid) with an amine functional substrate as studied using contact angle measurements, These studies performed in 0.6M salt solution as a function of function of pH showed that the oil droplet barely adhered to the aminated substrate at a pH that is less than 6 or more than 10, whereas the adhesion was most tenacious at a pH near pH=8, where the de-protonated dodecanoic acid could interact with the protonated amine. In another related experiment, it was found that the efficiency of the extraction of DDA containing Oil-in-water emulsion with amine functionalized particles was maximum at a pH close to 8. We emphasize that those previous studies are consistent with the current Bathochromic titration results in that the carboxylic acid groups do deprotonate in 0.6 M salt solution, and it does so at a pH in the vicinity of 7.5.