LABORATORY PROCEDURES FOR PLANT CELL LINES
PC/1998/3/1.2 Appendix 1
Standard Procedure: Measurement of Dry Weight Percentage of Fresh Cells
For different purposes dry weight percentages of fresh cell material have to be measured including the characterization of a growth curve of callus or suspension cells. This is in order to find the optimum growth stage for cryopreservation, and also to relate certain quantitative characters like product content, enzyme activity or viability measures (TTC Test) to the cell number or cell weight.
1. An empty petri-dish (diameter 60 mm) is weighed (including the lid).
2. The weight of the empty petri-dish is written on the lid.
3. A certain amount of callus or filtered suspension cell material is put into the petri-dish.
4. The petri-dish (including lid and cell material) is weighed again and the weight written on the lid of the petri-dish.
5. The petri-dish with the cell material is placed into an oven at 60 °C for three days.
6. The petri-dish (including dried cell material and lid) is weighed again and the weight is written on the lid.
7. From the three weights: A = weight of empty petri-dish
B = weight of petri-dish with fresh cell material
C = weight of petri-dish with dried cell material
the dry weight percentage = (C-A) / (B-A) x 100 is calculated.
Guidelines prepared for CABRI by DSMZ, 20 Jan. 1998
© The CABRI Consortium 1999-2013.