High throughput feeding system for primary screening processes (Fed-Batch Microplates)
Due to changes of raw materials, common chemical processes will prospectively be replaced or supplemented by biotechnological methods of production. Biotechnological production is based on the cultivation of mostly genetically modified microorganisms or various animal cells.
The development of a biotechnological processes starts with the search for suitable production strains and conditions. Therefore thousands of strains are cultivated and examined for their capability of product formation. This part of the development is called ‘primary screening’ and is best designed as a high throughput procedure. For this purpose, micro plates are commonly applied since they enable many cultivations with only a little requirement for space. Currently, the microorganisms are cultivated in batch mode during primary screening. For this purpose the applied nutrient solution shows a high concentration of substrate and buffer, which covers the demands of the organism over the whole period of cultivation. However many microorganisms show reduced or even no product formation under these conditions. Only at the very end of the cultivation when substrate concentrations are low, product formation starts. Strains selected in batch screening conditions will show high productivity when substrate is available in excess, osmotic pressure is high and pH-values are suboptimal. Nevertheless these conditions are far away from the conditions applied in production scale where there are feeding systems (Fed-Batch process) and pH-regulation. This is why strains selected in batch mode during primary screening mostly disappoint in production conditions.
The major target of this project is further development of micro plates with integrated polymeric-based feeding-systems. In these plates substrates and possible other substances can be released in defined rates and with high reproducibility. In these Feed Plates fed-batch cultivations can be performed without any additional effort and avoid common complications found during batch mode in primary screening.