BioProcess Analytical Technology(BioPAT) Laboratory

BioProcess Analytical Technology (BioPAT) Laboratory

  • Comparative Profiles of Different Process Variables
  • BioPAT Team
  • Bio-Calorimeter
  • Production of Hyaluronic acid (HA) from <i>Streptococcus zooepidemicus</i>
  • Pichia Pastoris Platform for Recombinant IFN-alpha Production


Biocalorimeter
There are basically two methods to measure the effects of metabolic activities in microbial processes; the first approach is the calorimetric method in which devices specially constructed for this purpose called microcalorimeters were used by many researchers to study thermodynamical behaviour of many biological transformation. Microcalorimeters were developed first and reached sufficient sensitivity for biological process monitoring.

However, this approach possess the disadvantage that the environment for the organism in which the metabolic heat is measured, is different from the environment in which the process takes place. This problem has been resolved by the advent of bench-scale calorimeters. They have been used in quantitative studies on microbial growth and product formation. In the second approach, the metabolic heat production is measured in the bioreactor itself to eliminate the problems encountered in microcalorimetric measuring devices.
Calorimetry plays a more important role in quantitative engineering related studies and in bioreactor control, the meaning of microbial heat release must be understood and the quantitative relationship of the heat evolution rate with other relevant process variables, such as biomass concentration, growth rate, Carbon di oxide evolution rate, and so on must be elucidated. Heat has often been considered as nonspecific information, which may account for some prejudices in the field of biocalorimetry. Calorimetric signals are the indication of a rapid metabolic change occuring inside the cell. Conventional calorimetric studies were aimed at analysing metabolic profiles of an organism. Moreover instantaneous calorimetric signal response is quicker than any other PAT analyzer tool. Therefore exploring biocalorimetric feature becomes inevitable to our research.


Dielectric Spectroscopy
Dielectric spectroscopy quantifies cell number in a bioreactor, through which the cell growth can be visualized and monitored online. This system is found to be efficient in such a way that coupling with other PAT analyzers, the specific growth rate of a biomass could be obtained without any offline analysis. A small electric field generated by the probe present inside the broth tends the ionic solutions to move towards corresponding electrodes. Media broth and cytoplasm are basically ionic and conductive in nature, but plasma membranes are non conductive. So the ions in the cytoplasm get accumulated towards plasma membrane, thus acting as capacitors. The cells with intact plasma membrane alone be accounted in the system neglecting dead cells. The cumulative capacitance values correspond to the viable cell number in the system and ranges in pF level.
The dielectric probe made up of ceramic material and contains rings at its peripheral that produces electric field. The generated electric field is concentric over the probe tip and response is obtained as Capacitance(pF/cm) and Conductance(mS/cm) values. The knowledge of online biomass values of both cell quantity and cell physiology is critical for a process engineer to develop system producing high titre of recombinant proteins.