Table 1. Current FET Sensor Technologies for Physiological Parameter Measurements at Single Cells.

FET design	measured quantities	nanometric FET	used for intracellular measurements	used for extracellular analyte mapping	ref
flat Si channel	electric potential	no	no	no	39
free-standing kinked Si nanowire	electric potential	yes	yes	no	1
upright SiO2 nanotube branch on top of a nanoscale FET	electric potential	yes	yes	no	40
gold-coated pipet with carbon nanotube network as channel	Ca2+ concentration (range 100 pM–1 mM)	yes	yes	no	41
PPy on dual carbon nanoelectrode	pH (range 1–7.5) ATP concentration (range 10 nM–1 mM)	yes	yes	yes	this work