Table 5.

Different types of transducers and the measured property for tissue engineering applications

Type of transducers	Measured property	Compatible with bioreactor?	Example/reference
Electrochemical	Potentiometric, Amperometric, Conductometric, Nanotechnology, Bioelectronics	Yes	Electrochemical immunosensors integrated into bioreactors for continual monitoring of cell secreted biomarkers Riahi et al. (2016)
Protein	Immunosensor	Yes	Glucose monitoring in living cells using single fluorescent protein-based sensors Hu et al. (2018)
Electrical	Surface conductivity, Electrolyte conductivity	Yes	Electrical Impedance Spectroscopy cell monitoring in a miniaturised bioreactor Martínez-Teruel et al. (2013)
Optical	Fluorescence, Adsorption & Reflection	Yes	Low-cost calibration-free pH sensing with disposable optical sensors (Ge et al. 2012)
Light	Bioluminescence	Yes	Real-Time Bioluminescence Imaging of Cell Distribution, Growth, and Differentiation in a Three-Dimensional Scaffold Under Interstitial Perfusion for Tissue Engineering Vila et al. (2016)