BAPTA AM, calcium chelator

BAPTA AM is a membrane-permeable calcium chelator that, once inside cells, is converted into BAPTA by cytoplasmic esterases. It’s commonly used to control cytosolic calcium levels (Kd = 0.11 μM), inhibit Kv channels, and study calcium’s role in cell signaling. BAPTA AM can also serve as a calcium indicator, with its absorption maximum shifting upon calcium binding (254/274 nm). Typical concentrations for cell signaling studies range from 10-100 μM. Due to its low water solubility, mild detergents like Pluronic® F-127 are needed to aid cellular loading.