MAPTAM

MAPTAM is a cell permeable intracellular Ca2+ chelator that can be loaded non-invasive into cells by incubation. MAPTAM itself does not bind calcium, but once inside the cell is converted into it's derivative Dimethyl-BAPTA by cytoplasmic esterases. This type of calcium chelators are commonly used to form calcium buffers with well-defined calcium concentrations. By injecting the chelators into cells or by incubating cells with the AM ester form of the chelators, one can control the cytosolic calcium concentration, an important means to study the roles of calcium. Key advantages of these calcium chelators include relative insensitivity toward intracellular pH change and fast release of calcium. Recent studies have shown that BAPTA derivative might have microtubule disruptive activity (unrelated to it's calcium chelating activity) and should be used with caution in studies of cytoskeleton-related cell functions.