I am trying to quantify (or even be able to detect) very small concentrations of phenolic acids in protein-phenolic acid complexes. The expected concentration is really tiny 1-3 phenolic acid molecule/ protein molecule. I was thinking that a dye specific for phenolic acids would be a good way to identify phenolics acids in such situations. Quantification is optional even some qualitative results (presence vs absence of phenolic acids) will do.

Any ideas?