Near-infrared spectroscopy in upstream bioprocesses

The quality of upstream processes and their products strongly depends on the control of all influencing parameters. However, several relevant parameters are not measured in standard bioreactor systems. Near-infrared spectroscopy (NIRS) is one promising technology capable of becoming the missing link in sensor technology. This review gives an overview of the technological principles and the technological progress. A broad range of possible applications is presented, forming in its entirety a valuable toolbox for process risk mitigation. Recent applications of NIRS in upstream bioprocesses are discussed. Moreover, the review includes regulatory aspects in implementation, calibration and validation of NIRS instrumentation and models.