BAPTA

BAPTA

Names
IUPAC name 1,2-bis(o-aminophenoxy)ethane-N,N,N′,N′-tetraacetic acid
Identifiers
CAS Number	85233-19-8
3D model (JSmol)	Interactive image
ChEBI	CHEBI:60888
ChemSpider	94562
ECHA InfoCard	100.157.377
PubChem CID	104751
UNII	K22DDW77C0
CompTox Dashboard (EPA)	DTXSID30234432
InChI InChI=1S/C22H24N2O10/c25-19(26)11-23(12-20(27)28)15-5-1-3-7-17(15)33-9-10-34-18-8-4-2-6-16(18)24(13-21(29)30)14-22(31)32/h1-8H,9-14H2,(H,25,26)(H,27,28)(H,29,30)(H,31,32) Key: FTEDXVNDVHYDQW-UHFFFAOYSA-N InChI=1/C22H24N2O10/c25-19(26)11-23(12-20(27)28)15-5-1-3-7-17(15)33-9-10-34-18-8-4-2-6-16(18)24(13-21(29)30)14-22(31)32/h1-8H,9-14H2,(H,25,26)(H,27,28)(H,29,30)(H,31,32) Key: FTEDXVNDVHYDQW-UHFFFAOYAD
SMILES O=C(O)CN(c2ccccc2OCCOc1ccccc1N(CC(=O)O)CC(=O)O)CC(=O)O
Properties
Chemical formula	C22H24N2O10
Molar mass	476.433
Density	1.494 g/cm3
Melting point	177 to 179 °C (351 to 354 °F; 450 to 452 K)
Except where otherwise noted, data are given for materials in their standard state (at 25 °C [77 °F], 100 kPa).

BAPTA (1,2-bis(o-aminophenoxy)ethane-N,N,N′,N′-tetraacetic acid) is a calcium-specific aminopolycarboxylic acid. The presence of four carboxylic acid functional groups makes possible the binding of two calcium ions. The extensive flexibility of the carboxylate ligands is critical to the coordination of calcium and other metal ions. Due to its properties, it is used in research to chelate Ca²⁺, similarly to EGTA and EDTA.

There is a range of reported values for the dissociation constant of BAPTA, though 0.2 μM appears consistently.^[1] The rate constant for calcium binding is 500 μM⁻¹ s⁻¹.^[1]

See also

• EDTA
• EGTA
• Fura-2

References