BAPTA-AM is a calcium chelator that is cell-permeable and selective, blocking hERG, hKv1.3, and hKv1.5 channels (IC50=1.3/1.45/1.23 μM). BAPTA-AM has a 105-fold higher affinity for Ca2+ than for Mg2+, and can be used for the role of calcium in cell signaling.

Kv1.5 (human, HEK293 cells):1.23 μM, Kv1.3 (human, HEK293 cells):1.45 μM, ERG channel (human, HEK293 cells):1.3 μM

METHODS: Chondrocytes were treated with BAPTA-AM (10 μM) and FAC (100 μM) for 24 h. Intracellular ROS levels were measured using the Reactive Oxygen Species Assay kit.
RESULTS: FAC promoted ROS production and this effect was inhibited by the calcium chelator BAPTA-AM. [1]
METHODS: Rat fibroblast RAT2 and Xenopus cells were treated with BAPTA-AM (50 μM) for 1 h, and microtubule depolymerization was detected by Immunostaining.
RESULTS: BAPTA AM treatment for 30 min resulted in almost complete disassembly in most cells, and microtubules were uniformly depolymerized in cells within 60 min. [2]

METHODS: To investigate the effect on ethanol-induced locomotor activity, BAPTA-AM (0-10 mg/kg, Cremophor EL 1.25% (v/v) in distilled water) was injected intraperitoneally into Swiss (RjOrl) mice, followed by ethanol (0-4 g/kg) 30 min later.
RESULTS: Pretreatment with BAPTA-AM blocked the locomotor stimulus produced by ethanol without altering basal locomotion. On the contrary, BAPTA-AM reversed the ethanol-induced hypnosis. [3]
METHODS: To investigate the effect on LPS-induced blood-brain barrier leakage, BAPTA-AM (12 mg/kg, 0.01% pluronic acid in sterile saline) was injected intravenously into FVB mice, followed 30 min later by intraperitoneal injection of LPS (25 mg/kg).
RESULTS: BAPTA-AM reduced LPS-induced blood-brain barrier leakage. [4]

Instructions for use
I. Solution preparation
1. Prepare BAPTA-AM storage solution: Dissolve BAPTA-AM in anhydrous DMSO to prepare a 50 mM storage solution; (it is recommended to store at -20 ℃ or -80 ℃ in the dark after aliquoting).
2. Prepare working solution: Dilute BAPTA-AM storage solution into cell culture medium to a final concentration of 6-50 μM.
II. Cell preparation
1. Grow cells to an appropriate density. For adherent cells, they can be planted in culture dishes or culture plates; for suspended cells, adjust the cell concentration to 2×10^6 cells/mL.
2. Incubate cells with BAPTA-AM solution, usually at 37℃, 5% CO₂ for 30-60 minutes, with gentle shaking during the period.
3. Remove excess dye: After incubation, wash cells with calcium-free buffer to remove BAPTA-AM that has not entered the cells.
4. For adherent cells, they can be directly washed with calcium-free PBS; for suspended cells, the cells need to be collected by centrifugation and then resuspended with calcium-free PBS.
5. Detection of changes in calcium ion concentration: You can choose the appropriate detection method according to the experimental requirements:
Fluorescence microscope detection: observe the changes in fluorescence intensity in cells. The decrease in fluorescence intensity indicates a decrease in calcium ion concentration.
Flow cytometry detection: analyze the changes in fluorescence intensity in cells through flow cytometry.
Fluorescence spectrometer detection: measure the changes in fluorescence intensity of cell suspension.