Published online by Cambridge University Press: 14 March 2018
During the past decade there has been remarkable progress in understanding the behavior and function of biological cells. Progress was accelerated by the development of microscopic imaging techniques and fluorescent dyes that allowed investigators to visualize dynamic processes within subcellular compartments in heterogenous populations of living cells. These capabilities led to exciting new discoveries in cellular and molecular studies of a wide variety of cell types.
Efforts to study living cells under microscopic conditions are not without problems, however. The most vexing problem is phototoxicity caused by either illumination alone (endogenous toxicity) or illumination of fluorescent dyes loaded into cells (exogenous toxicity). In this report I provide an overview of these general types of toxicity as well as describe recent results that may shed light on how to reduce them.
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