A non-disruptive technique for loading calcium buffers and indicators into cells

Abstract

A simple technique which loads Ca2+-selective chelators into the cytoplasm of intact cells in suspension and avoids the disadvantages of previous methods is described. The chelators are made temporarily membrane permeable by masking their 4 carboxylates with special esterifying groups which then hydrolyze inside the cells, regenerating and trapping the original chelators. The method is demonstrated on [human] red cells, mast cells and lymphocytes.