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Multi-Parameter Systems for Highly Parallelized Optical Measurements

PreSens offers special systems for simultaneous online monitoring of multiple parameters, and highly parallelized measurements in a multitude of samples. These readers can directly be installed inside shaking incubators and allow non-invasive oxygen and pH monitoring in different cultivation vessels, or even optical biomass measurement in shake flasks. Our different multi-parameter systems are designed for culture monitoring applications from mL up to several L scale.

Featured Biomass System

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Watch the SFR vario Tutorial

Online Optical Biomass Measurements

The PreSens biomass measurement system SFR vario allows online monitoring of biomass development inside shake flasks. The measurement method is based on the detection of light scattered by particles inside the sample medium. The biomass measurements can be correlated with optical density (OD) and cell dry weight (CDW) by non-linear calibration models.
While cumbersome sampling had to be conducted so far, this reader now allows to follow biomass development online and detect even smallest changes.  The components for optical biomass determination – an LED and photodiode - were implemented in the established SFR Shake Flask Reader optics, so a monitoring device was created which allows simultaneous pO2, pH and biomass monitoring. While oxygen and pH are determined with optical sensors integrated in the shake flask, biomass measurements can even be conducted in standard flasks without additional sensors.

Biomass Measurements - Always at the Right Moment

During shaking a liquid sickle forms inside the shake flask, and optical biomass measurement should always be taken at the moment of maximum liquid above the optics. The SFR vario’s integrated acceleration sensor determines the device position during the shaking movement. This way the time of optical biomass measurement can be adjusted to a moment within a time frame of sufficient liquid above the sensor. With the PreSens Flask Studio Software the optimal biomass measurement angle for a certain medium (e. g. more viscous) and the applied shaking speed can easily be determined, so optimal biomass measurement results can be achieved.