Tetrasodium 1，2-Bis(2-aminophenoxy)ethane-N，N，N'，N'-tetraacetate

BAPTA tetrasodium is a selective chelator for calcium. BAPTA tetrasodium, as calcium indicator, has high selectivity against magnesium and calcium. BAPTA tetrasodium is widely used as an intracellular buffer for investigating the effects of Ca2+ release from intracellular stores or influx via Ca2+-permeable channels in the plasma membrane. BAPTA tetrasodium can also inhibit phospholipase C activity independently of their role as Ca2+ chelators.

BAPTA (0.3-30 渭M; 1 h) can be used for the prevention of [Ca²⁺]-induced cell damage, but disturbe calcium signalling in isingle differentiated NH15-CA2 neuroblastoma and glioma hybrid cells^[3].
BAPTA (0-10 mM) inhibits phospholipase C (PLC) activity in a dose-dependent manner, and is unrelated to Ca^2+[2].

[1]. R Y Tsien, et al. New calcium indicators and buffers with high selectivity against magnesium and protons: design, synthesis, and properties of prototype structures. Biochemistry. 1980 May 27;19(11):2396-404.  

[2]. Roger C Hardie, et al. Inhibition of phospholipase C activity in Drosophila photoreceptors by 1,2-bis(2-aminophenoxy)ethane N,N,N',N'-tetraacetic acid (BAPTA) and di-bromo BAPTA. Cell Calcium. 2005 Dec;38(6):547-56.  

[3]. M B Collatz, et al. Intracellular calcium chelator BAPTA protects cells against toxic calcium overload but also alters physiological calcium responses. Cell Calcium