Nanoelectrochemical analysis inside a single living cell

This critical opinion reviews the methods to construct and apply electrodes for analysis inside single cells and of single organelles. Nanoelectrochemical methodology, with an emphasis on nanoelectrode construction and analysis of metabolites, neurotransmitters, reactive oxygen and nitrogen species, glucose, oxygen, hydrogen peroxide, and ions in cells are discussed for measurements from cytoplasm to single organelles.