Process and equipment for measuring optical properties by retroaction
Inventor: Robert LONGIN, Laurent GAILLON
Description of invention:
The culture of microorganisms (or other cells) and the measure of their concentration at several stages of development is often necessary not only in laboratories but also in industries. This quantification can be made directly on sample by counting the cells or by dry-weigh measurement
Such methods are long and tedious and it is easier to make an indirect evaluation of the cells rate by measuring optical properties, like turbidity.
In this field, most of actual devices are not able to measure high level of turbidity, and samples need to be diluted and in big amount. The purpose of this invention is to remedy this situation with new processes and equipments allowing the measure on line of optical properties of media in appropriate reactors and their control.
The present equipment is able to measure, with a high precision, the turbidity on a large range of values (from 45 up to more than 17 000 NTU). In the next future, we plan to adapt the apparatus to read the absorbance and the fluorescence.
Moreover, this equipment is of small size, cheap, easy to use and can be adapted on bioreactors. It is also possible to fit, with this device, batteries of 4 up to 24 microfermentors (called multi-micro-fermentors, MMF, each with volumes of 10 to 60 ml), controlled with just one microcomputer, for simultaneous measurements of the turbidity of cells cultures, from 0,2 to more than 75 optical density units.
This invention also deals with a bioreactor equiped for automatic sampling at predeterminated values of turbidity, absorbance or fluorescence, and also an automatic dilution reactor for cyclic or other continuous cultures.
Several applications for this device are envisaged by inventors. First, the integration of this equipement in a automated culture in tube systems allows physiological studies and screening, enrichment or evolution of microorganisms or eukariotic cells. Integration of this device in bioreactors is of particular interset for the following and the supervision of fermentations. This invention can also be useful for the water or industrial effluents treatment and analysis.
Contact : Christophe Poquet, Business Development Manager - Office of Technology Transfer
Institut Pasteur – 28 Rue du Docteur Roux – 75724 Paris Cedex 15 FRANCE
Tel : 33 (0)1 40 61 33 97 - Fax : 33 (0)1 184.108.40.206 – email : firstname.lastname@example.org