ENDRESS+HAUSER  OUSBT66-AA05A1A

NIR absorption sensor for the measurement of cell growth and biomass

The OUSAF11 sensor measures the VIS/NIR absorption of liquids.

• Cell growth in bacterial fermentation and applications in mammalian cell cultures
• Biomass in fermentation processes
• Monitoring of algae concentration
• Monitoring of crystallization processes
• Measurement of solids in:

• Increased product yield thanks to fast and reliable absorption measurement in fermentation and crystallization applications
• Highest linearity and wide measuring range with LED lamp
• Suitable for pharmaceutical use:
  • Stainless steel 1.4435 (AISI 316L)
  • Sealless sapphire window without gaps
• High degree of product safety:
  • Sterilizable and autoclavable
  • CIP/SIP-resistant
• Cost-effective, time-efficient calibration with traceable plug-on filters
• For use in a wide range of applications:
  • Variety of optical path lengths for different cell cultures and concentrations
  • Process connection Pg 13.5 for installation in assemblies or head plates
  • Suitable for lab-scale, pilot-scale and production-scale bioreactors
  • Available in different lengths for different immersion depths

The measuring principle is based on the Lambert-Beer law.

There is a linear dependency between the absorption of light and the concentration of the absorbing substance:

A = -logA m = ε . c . OPL
A ... absorption, A m ... absorption measured by detector
ε ... Extinction coefficient
c ... Concentration
OPL ... Optical path length

A light source emits radiation through the medium and the incident radiation is measured on the detector side.

The intensity of the light is determined by a photodiode and converted to a photocurrent.

The subsequent conversion to absorbance units (AU, OD) is performed in the associated transmitter.