Single Use Capacitance Measurements of Viable Cell Volume

Transcription

1 Single Use Capacitance Measurements of Viable Cell Volume Stuart Tindal Process Analytics Product Manager November 2014 Page 1

2 Agenda Market Demand Technical background Integration and automation Results November 2014 Page 2

3 Single Use: Strong Market Demand for Biomass Measurement Cell Density 64.0% Cell Viability 50.0% Glucose 50.0% pco % Flow 32.8% Most-wanted Single-Use sensor (Aspen Brooks Report 2011): November 2014 Page 3

4 BioPAT ViaMass allows single-use biomass monitoring November 2014 Page 4

5 Alternative Biomass Measurements Offline Methods Trypan blue exclusion FACS analysis Offline counter Cells need intact membrane, subjective method Cells need intact membrane and active enzymes mostly based on Trypan blue exclusion with CCD camera counting Highly time consuming, no direct Feedback Dry weight / Wet weight not specific, mostly used in microbial fermentation Online Methods OD / Turbidity measurement mostly used in microbial fermentation Dead cells and debris contribute to the signal as well November 2014 Page 5

6 SU Biomass Measurement Added Value Real-time viable cell volume monitoring data Automated process control and process modeling Automated substrate feed strategies Harvest point determination Optimal time of infection for viral production Benefits Lower risk of contamination due to limited sampling need Reduced risk of unrepresentative samples (manual handling) Decreased labor and laboratory costs for offline analysis November 2014 Page 6

7 Agenda Market Demand Technical background Integration and automation Results November 2014 Page 7

8 Basic principle of capacitance measurement November 2014 Page 8

9 The cell ions in a shell Cytoplasmic Lipid membrane impermeable to free flow of ions November 2014 Page 9

10 Influence of electric field will polarise viable cells Electronics controlling the electric field Polarising ions available in the cytoplasm and suspending media Cell Direction of the field November 2014 Page 10

11 Dead and ruptured cells cannot be polarized Electronics controlling the electric field Cell with badly ruptured plasma membrane Plasma membrane fragments Direction of the field November 2014 Page 11

12 Gas bubbles, protein and debris have no chargeable surface or ion rich cytoplasm Electronics controlling the electric field Gas bubble Solid particle impermeable to ions Solid particle permeable to ions No ions available within the particles Direction of the field November 2014 Page 12

13 BioPAT ViaMass In situ four pin electrode probe Only living cells polarized Living biomass is measured Dead cells invisible to measurement field Single entry point probe Sensitivity of measurement field approx. 25mm November 2014 Page 13

14 Agenda Market Demand Technical background Integration and automation Results November 2014 Page 14

15 Challenges BioPAT ViaMass Single use integration Single use - Plastic RM - Rocking motion Sourcing material Manufacturing consistency Bio-compatible Capacitance [pf/cm] Filter on Filter off STR - Pressure Time [min] November 2014 Page 15

16 BIOSTAT RM - System setup November 2014 Page 16

17 BIOSTAT STR - System setup November 2014 Page 17

18 Automation BioPAT MFCS & BioPAT SIMCA Recipes for process automation Automatic event-based control of cultivations to assure batch-to-batch consistency Fully automated process steps based on cell numbers, for robust processes and reduced labor work DCU Integration Direct display of Capacitance Cell volume Quick and simple process monitoring November 2014 Page 18

19 Agenda Market Demand Technical background Integration and automation Results November 2014 Page 19

20 Sartorius Stedim in house results in RM 10L Viability [%] 90 Viable Cell Volume [%] Capacitance [pf/cm] Time [h] Viable cell volume = Viable cell density Viable cell diameter - Results of a CHO cultivation in a CultiBag RM 10 L - Capacitance signal of the BioPAT ViaMass sensor is compared with viable cell density from offline Cedex HiRes - Cedex reveals average cell diameter as well - Average cell diameter and viable cell density result in viable cell volume - Error of viable cell density is of the same magnitude as the reference error of the Cedex Viable Cell Density [10^5/ml] Viable Cell Diameter [µm] November 2014 Page 20

21 Viable cell concentration and capacitance of the second cultivation over time which shows a normal cell growth for the Hybridoma cell line viable cell concentration in cells*ml E E E E E E E capacitance in pf*cm -1 Time in hrs viable cell concentration Capacitance November 2014 Page 21

22 Flow through cytometer of Hybridoma batch cultivation Batch cultivation time November 2014 Page 22

23 Viable cell concentration and capacitance of CHO DG44 cell line E E Capacitance [pf/cm] E E E E+05 Cell density [N/mL] 3.50E Time in hrs 0.0E E E+06 Cell density iin Nl/mL 2.00E E E E Capacitance [pf/cm] 0.00E November 2014 Page 23 Time in hrs 0

24 Total cell volume and capacitance of CHO DG44 cell line capacitance in pf*cm Time in hrs Viable cell volume = Viable cell density Viable cell diameter total cell volume in ml capacitance in pf*cm total cell volume in ml Time in hrs November 2014 Page 24 0

25 Correlation of on-line data to off-line measurement capacitance in pf*cm R² = capacitance in pf*cm R² = total cell volume in ml total cell volume in ml November 2014 Page 25

26 2 nd internal application runs in RM 50L Viability [%] Viable Biomass [%] Capacitance [pf/cm] Time [days] Viable Cell Density [10^5/ml] Viable Cell Diameter [µm] Wet Cell Weight [g/l] Improved rocking motion filter November 2014 Page 26

27 Thanks to The Sartorius Stedim Process team Analytics team Plastics team Injection molding team Aachen University November 2014 Page 27

28 Thank you. November 2014 Page 28