Online Biomass Sensors

Manufacturer: Aber Instruments Ltd.

The FUTURA System measures an electrical property of cell suspensions called Capacitance. Academic and industrial research has demonstrated a correlation between this property and live biomass. Aber’s patented technology converts capacitance into a live biomass reading, typically Cells/ml or g/l for Spun Solids dry weight. However, other units can be derived from the raw capacitance measurements; these may be more relevant to the chosen application. Futura also measures the Conductivity of the medium, in millisiemens per centimetre (mS/cm). Conductivity is not used to measure biomass but is indicative of the production or utilization of ions by the cell suspension, e.g. pH control and other fermentation processes. FUTURA comprises 3 primary hardware components together with a variety of software products system configuration, data logging, data analysis and frequency scanning.

The hardware components include: 
1. A probe that is immersed in a culture of live cells.
2. A communications Hub or Connect module. The FUTURA Connect modules 
    come in three variants, allowing connection of one, four or eight 
    FUTURA-probe combinations. For each connected FUTURA the FUTURA Connect 
    can simultaneously output Current Loop and Modbus RTU signals for use with 
    PLCs and other control systems whilst optionally interfacing with a PC over a 
    single USB cable, allowing independent control, calibration, monitoring and 
    logging of all Futuras connected to the system using Aber software.
3. The Futura instrument itself which is the main processing engine of the 

Two variants of the FUTURA are available and connectable to all types of probes:

Standard FUTURA (SF)
Lightweight housing suitable for most bioreactors and is ideal for 25 mm diameter side mounted probes and 12 mm probes on vessels where the centreline of the probe is greater than 15 mm from the centreline of the vessel. Supplied with a 2 m cable.

Standard Remote FUTURA (SRF)
The design of the Standard Remote FUTURA is best suited to small vessels where the available head space is often limited to a small footprint. It Incorporates a slim, light-weight pre-amplifier making it ideal for small bioreactors with as low as 100 ml working volume. The main FUTURA housing can be mounted away from the bioreactor vessel (up to a maximum of 1 m).

Technical Specifications
•    Frequency Range: 50 KHz to 20 MHz
•    Measuring Ranges:
         o    Capacitance: 0.0 to 400 pF/cm
         o    Conductivity: 1.0 to 40 mS/cm +/-0.1 mS/cm
         o    (Higher ranges available with compatible probes)
•    Cell Concentration Range: Depends on cell sizes but typically:
         o    Yeast (6 ?m): 106 cells/ml to 1010 cells/ml
         o    Bacteria (1 ?m): 109 cells/ml to 1013 cells/ml
         o    Animal Cell (12 ?m): 105 cells/ml to 109 cells/ml
         o    Plant Cell (50 ?m): 103 cells/ml to 107 cells/ml
•    Resolution:
         o    0.1 pF/cm.
         o    Yeast: 0.05 g/L
         o    Bacteria: typically 0.1 g/L dry weight or 2x109 Cells/ml for E. coli
         o    Animal Cells: 1 x105 Cells/ml
         o    The relationship of these capacitance values to biomass levels 
               depends upon the cell type and cell line.
•    Stability: Better than ± 0.2 pF/cm at constant temperature with standard 
      conductivity solution of ~12 mS/cm
•    Linearity: Better than ± 1% over 100 pF/cm
•    Precision: Typically <±0.5 pF/cm, no filter active.
•    Power Supply: 24V DC power is typically supplied by an Aber Hub running 
      on 110 V AC to 240 V AC mains.
•    Environmental: IP65 rated ; Recommended ambient operating temperature 
      range: 5 °C to 40 °C
•    Weight (SF): 375 g
•    Weight (SRF): Main enclosure: 211 g; Remote enclosure: 203 g

Aber Instruments has a wide range of probes to suit all applications, they are available in 12 mm diameter ideal for small bioreactors and 25 mm diameter for larger vessels. All probes are Electro-polished and passivated. Options for USP class VI and FDA CFR21 177 certificates. By default a probe is shipped with a simple standard certificate of traceability. If you wish to have a full breakdown of all the materials used in the production of a probe then please order the ‘Probe Certificate of Conformance’ package

Request product info