Question

What are the advantages of stirred tank bioreactors over shake flasks?

Answer 1

Hint: Shake flasks and bioreactors are both important tools for bioprocessing but are very different in many respects. Bioreactors clearly offer a way wider range of capacities, but more interesting are the differences in overall performance, the distinctive functionalities offered, and also the consequent benefits for particular applications.

Step by step answer:Shake flasks are used for many years to cultivate bacteria and fungi, additionally as plant and animal cells in suspension. They're an easy-to-use and cheap choice for basic applications, like organism screening, media design, and early process development. All that's needed may be a flask and a shaker to maneuver it. The user doesn't need technical knowledge, advanced equipment, or sensing and control technologies. This very simplicity, however, is that the biggest disadvantage. Shake flasks don't provide detailed insight into culture performance or the chance to watch and control the method parameters.
 -Shaken not stirred: While bioreactor cultures are stirred for mixing, shake flasks are agitated on shakers, usually with a gyration. The agitation mode, direction, and speed influence the fluid dynamics, and so the heat transfer and mass transfer within the culture, leading to a selected performance.
-Fluid dynamics: Besides temperature and nutrient supply, oxygen availability is significant to microbial and cell culture growth. In shake flasks, the oxygen transfer takes place via two liquid surfaces: the majority liquid surface and therefore the liquid film on the wetted shake flask wall. The oxygen transfer rate (OTR) in shake flasks is decided by the flask size and shape, agitation speed, filling volume, and ambient conditions.
-Limited insight and control: Cultivation processes in shake flasks are never under true control. These systems don't leave online measurements of critical process parameters like temperature, dissolved oxygen, or optical density, because the flasks cannot be easily equipped with sets of sensors. Direct control of those parameters is additionally impossible. Temperature and oxygen, as an example, can only be regulated by controlling ambient conditions in a closed shaker system or a cultivation room. Controlling a bioprocess in shake flasks would involve lots of manual add taking samples, making offline measurements, and adjusting levels manually.
-Bioreactors are closed systems equipped with multiple sensors, motor-driven impellers for agitation, and instruments for temperature control, gassing, and therefore the supply of liquids. Associated software facilitates online monitoring and control of all relevant process parameters and infrequently allows for integrated analytics and comprehensive processing furthermore.
-Real-time monitoring enhances process understanding: Bioreactors are equipped with multiple sensors that yield real-time observation. Temperature, dissolved oxygen, or biomass are measured constantly and displayed numerically and graphically. Exhaust, metabolites, and redox potential are often calculated from the measured process parameters. Process protocols, set-points, feeding and gassing profiles, and more may be pre-programmed. The bioreactor control units then facilitate the interaction of hardware and software to enable precisely controlled bioprocessing in line with predefined protocols. This combination of real-time monitoring, precise control, and detailed reporting changes the black-box of a shake flask cultivation into in-depth bioprocess insight.
 -Scaling up: Industrial-scale bioprocesses require the utilization of bioreactors. The challenge is to proportion the assembly process from small-scale development to bench scale, then to pilot and production scales. Having the ability to optimize the method for product formation, quality, and yield at a little scale and so scale it up with minimal adjustments to production scale can save an excellent deal of time and money.
-Comprehensive software: The advantages of bioreactor processes over shake flask cultivations for complex bioprocesses are all the more convincing when bioprocess management software is applied. Special software solutions can interconnect multiple laboratory devices and help to automate the method. They'll apply the Design of Experiment and process modeling, can support comprehensive data analysis and might connect with historians and central data storage tools. Process Analytical Technology (PAT) approaches and Quality by choice (QBD) is facilitated.

Note: Bioreactors provide users with almost unlimited flexibility, functionality, and freedom of action, but cost much more and need well-educated operators. Shake flasks, however, also have a place for simple screening and media development.