ADA is a biological buffer[1]. ADA can serve as a chelator[2].
[1]. T Minami, et al. Identification of metallothionein isoforms with capillary zone electrophoresis using a polyacrylamide-coated tube. J Chromatogr B Biomed Appl. 1996 Oct 25;685(2):353-9. [2]. Birte M Gerken, et al. Tweezing-adsorptive bubble separation. Analytical method for the selective and high enrichment of metalloenzymes. Anal Chem. 2005 Oct 1;77(19):6113-7.