On-line monitoring of hybridoma cell growth using a laser turbidity sensor. 
A high-sensitivity turbidity probe was used for on-line monitoring of the cell concentration in batch hybridoma cultivation.  Good correlation between off-line cell counts and the linearized sensor signal was found.  The quality of the signal was sufficiently high to provide for on-line estimation of the specific growth rate using an efficient filtering procedure.  These positive results suggest that such laser turbidity sensors will facilitate development of systems for on-line monitoring and control of animal cell cultivations.