 Isolated cells can be used to study how cells work, how they change in response to disease, and how they are affected by drugs.An example of an experimental technique which uses isolated cells is patch clamp electrophysiology, used to study how charged particles flow across the cell membrane.Complementary techniques include calcium fluorescence imaging using dyes that emit light in response to calcium to measure how calcium is regulated within the cell, and immunocytochemistry which uses antibodies tagged with a fluorescent marker to identify where proteins are located within a cell.