| Accurate cell counts and viability assessments of
homogeneous cell suspensions can be accomplished
by a variety of methods. The Guava ViaCount assay
provides cell count and viability data for cell suspensions
from a variety of cell lines, quickly and easily.
However, cell samples containing clumpy aggregates
present a challenge by any method, manual or automated.
We have developed the Guava ViaCount CDR
assay to address this problem. The assay uses Guava
ViaCount CDR Cell Dispersal Reagent to gently disaggregate
clumps, and Guava ViaCount Reagent to
stain cells for count and viability assessment. The
assay was optimized and validated using CHO-K1
cells that were adapted to suspension culture in
serum-free medium. Significant improvement in the
count accuracy was attained for this assay, with good
linear correlation to hemacytometer counts (R2 >
0.93) over a broad range of cell densities (5 x 105 – 1
x 107 cells/mL) and culture conditions (50 - 95%
viable, 17 - 87% aggregation). Assay results were
highly reproducible, with % CV for replicate cell
count values ranging from 3 - 7% and % CV for
replicate viability measurements of 1 - 2%. |
