Most immersion probe methods are limited in the range of biomass growth they measure. Not the BE2100! The BE2100 sensor employs a novel method of optical monitoring that responds linearly to biomass over an ultra-wide range of growth: from less than 0.1 to greater than 300 OD units. The plot on the left above shows the BE2100 response to a batch culture of S. cervisiae grown at low biomass to a maximum OD of 2.5. The raw BE2100 output is strongly correlated with the OD

that was measured off-line by dilution and spectrophotometry at 600 nm (R2 = 0.98).

The same BE2100 sensor was used to measure the growth of E. coli in a fed-batch culture. Off-line OD measurements indicated that the culture reached a maximum OD greater than 120. Although high for E. coli, this OD was well within the linear range of the BE2100—the square of the correlation coefficient between the BE2100 raw output and the off-line OD measurement was 0.99.