5,5'-Dimethyl BAPTA tetrapotassium is a water-soluble, extracellular membrane metal chelator with relative selectivity for calcium ions[1].
References
[1] B Z Paul, et al. Platelet shape change is mediated by both calcium-dependent and -independent signaling pathways. Role of p160 Rho-associated coiled-coil-containing protein kinase in platelet shape change. J Biol Chem. 1999 Oct 1;274(40):28293-300. DOI:10.1074/jbc.274.40.28293