RELIABLE PERISTALTIC PUMPS FOR CONTINUOUS CULTURES

  • Highly reliable pumps
    with reproducible flow rates for bioprocessing techniques
  • The unique tubing compression technique
    for long tubing life and long-term stability of flow rates even with low-cost tubing
  • Flow rates remain constant for several weeks
    without the risk of tubing rupture in long-term experiments like continuous cultures, chemostat, perfusion
  • Variable speed pump
    for better precision e.g.: the speed of the peristaltic pump is regulated to attain the preset value of pH, during the addition of acid/base to the medium
  • Stackable and extremely compact peristaltic pump
    saves valuable bench space in your laboratory
  • Flow rate programming (up to 99 steps)
    and automatic switch-on and switch-off without using any timer e.g. programmed feed profile
  • Can also be used as a stand-alone instruments
    (e.g.: downstream processing experiments)
  • Remote controllable
    by PC, MINIFOR fermentor-bioreactor, fermentation software SIAM / Fnet
LAMBDA PRECIFLOW
pH control pump
0.2 µl/min - 600 ml/h
peristaltic pump LAMBDA PRECIFLOW

5 years warranty

PC-Programmable

LAMBDA MULTIFLOW
laboratory pump
0.2 µl/min - 600 ml/h
laboratory pump LAMBDA MULTIFLOW

5 years warranty

Programmable

LAMBDA HiFLOW
peristaltic pump
1 µl/min - 3,000 ml/h
feed pump LAMBDA HiFLOW

2 years warranty

Programmable

LAMBDA MAXIFLOW
peristatlic pump
3 µl/min - 10,000 ml/h
peristaltic pump LAMBDA MAXIFLOW

2 years warranty

Programmable

LAMBDA MEGAFLOW
peristatlic pump
0.02 ml/min - 60 L/hour
laboratory pump LAMBDA MEGAFLOW

Programmable

2 years warranty

What are the advantages of LAMBDA peristaltic pumps compared to conventional hose pumps?

The main advantage is the construction of LAMBDA peristaltic pump heads: The pump head’s unique compression mechanism reduces the mechanical strain on the tubing and the tubing compression is kept in the range of elasticity of the tubing.

As a result of LAMBDA's special tubing compression, the lifetime of tubing used (even lowest cost silicone tubing) is greatly extended and the flow rates remain constant for several weeks without the risk of tubing rupture in long-term experiments like continuous cultures, chemostat, perfusion. LAMBDA peristaltic pumps work well with low-cost tubing. The economy obtained by using low-cost tubing instead of tubing with stoppers or expensive special tubing material formulations pays the peristaltic pump back after the use of only about 80 m of tubing!

Flow rate programming (up to 99 steps) and automatic switch-on and switch-off without using any timer. Flow rate profile could be used for e.g.: pre-program the feed profile for fed-batch culture directly on the feed pump and run it automatically for 'n' number of times.

Application of highly reliable peristaltic pumps

Highly reliable LAMBDA peristaltic with stable and reproducible flow rates are applied for long term experiments in the laboratory. Pumps are specially developed for long term continuous upstream processes USP such as turbidostat, chemostat, perfusion, 3-stage fermentation and downstream processes (DSP):

  • Feed pump and harvest pump (fed-batch culture, continuous culture, chemostat, turbidostat, perfusion)
  • Controlled addition of nutrients, minerals
  • pH control (addition of acid, base, buffers)
  • Antifoam control (addition of antifoam agent)
  • Sampling at particular time interval
  • Feed flow rate profile (e.g.: pre-program the feed profile for fed-batch culture directly on the feed pump and run it automatically for 'n' number of times)
  • Sample addition/injection
  • Quantify the metabolic activity of the culture
  • Media dispenser
  • Process optimization with C-feed in fed batch
  • Pump media for filling agar plates (with foot switch)

pH control: pump speed control for automatic acid/base addition

Unlike the cheap and unreliable fixed-speed pumps, the flow rate of LAMBDA peristaltic pumps can be varied in the ratio 1:1000 during the addition of acid (or base) into the medium by the pH controller:  The peristaltic pump turns at full speed and reduces the speed as the preset value of pH is being attained. The pH regulation by "soft landing" is much more precise than by merely switching ON and OFF fixed speed pumps.

LAMBDA disagrees with the concept of offering fixed speed pump in fermentation/cell culture because the peristaltic pump quality and reliability is a crucial factor, which strongly affects the quality and productivity of the cell culture work.

Chemostat: How to use the LAMBDA Peristaltic Pumps with the LAMBDA weighing module?

Connected to the weighing module, the LAMBDA peristaltic pump will automatically add (remove) the medium from the working vessel to attain the pre-set weight.

In the chemostat, the culture weight is kept constant by feeding the medium at a constant rate (feed pump) and the culture is harvested at the same rate (harvest pump) to maintain the suboptimal growth rates of the microorganism. Unlike batch culture where growth time is limited to a few days, continuous cultures can run for several days or weeks at a steady state. Therefore, it is important to use a convinient system with reliable peristaltic pumps for a constant supply of medium, maintain aseptic conditions (LAMBDA easy sterility concept) and precise parameter control for highly beneficial long continuous culture experiments.

Cell growth kinetics: Pump-flow INTEGRATOR replaces OD measurement

LAMBDA offers a possibility to access the cell growth kinetics by measuring and recording the amount of base or acid utilized to maintain the pH of the culture constant. The LAMBDA pump flow INTEGRATOR transforms the impulses driving the motor of the pump into a voltage which can be recorded and displayed using the fermentation software (FNet or SIAM).

The trace obtained by the INTEGRATOR displays also an indication of growth problems, contamination and the extent of the biotransformation. It is an important parameter when cultures have to be compared in a series of fermenters/bioreactors.

Example: Cell growth produces CO2, which is acidic and to maintain the pH constant, this acid (which partially escapes) has to be compensated by the addition of base by a pH controller with a base pump (formation of metabolic acids and bases other than CO2 are of course also taken into account by this measurement globally). In a balanced cell growth, the production of CO2 and the need for a pH-correcting base are proportional to the growth (as the sum of all metabolic processes in the cell). Therefore, the amount of added pH correction solution is a precise indication of the growing extent of the culture. The controlled addition of acid equals (in principle) an analytical titration method and is, therefore, very precise.

How to apply the quantification?

The quantification of the LAMBDA INTEGRATOR signal can be obtained by using a base of known concentration and by calibrating the pump flow. Then, the value calibrated correlates to the growing extent measured by another suitable growth rate method. Afterwards, the mere signal of the pump flow INTEGRATOR allows precise and very inexpensive real-time growth kinetics.

Limits of inline measurement by optical density

Optical density (OD) measurement of the culture is not precise because the dead cells, air bubbles, precipitates and any other colour or turbidity formation also appear as an increase in cell concentration.

real-time fermentation data diagram

It is an example of the trace of an acid pump activity transformed by the INTEGRATOR, during biotransformation culture (red trend with two resets). The red trend is the only one which is clearly exponential, as it should be. By totalizing the consumption of acid, the extent of transformation and the immediate state of the culture can be derived. It is important information for the control and reproducibility of different cultures.