Biomedical Engineering Reference
In-Depth Information
TABL E 7.3. Experimental Matrix for the Harvest-Capture Modeling DOE
Standard
Order
Harvest
pH
Chaotrope
Concentration
Elution
Velocity
Load
Capacity
Block
1
1
0
0
0
0
2
2
1
1
1
1
3
1
1
1
1
0.
4
2
1
1
1
1
5
2
1
1
0
1
6
2
1
1
1
1
7
2
1
1
1
0
8
1
1
1
0
1
9
2
1
1
1
1
10
2
1
1
0
1
11
2
1
1
1
1
12
1
1
1
1
1
13
1
1.
0
1
1
14
1
1.
1
0
1
15
1
0
1
1
1
16
2
0
0
0
0
17
1
0
0
0
0
18
2
0
0
0
0
19
1
0
0
0
0
20
2
0
0
0
0
21
1
0
1
1
1
22
1
1
0
1
1
23
2
1
1
1
1
24
1
1
1
1
1
25
1
1
1
1
1
26
1
1
1
1
1
27
2
1
1
0
1
28
2
1
1
1
1
29
1
1
1
1
1
30
2
1
1
1
1
31
1
1
1
1
1
32
1
1
1.
Note: This D-optimal response surface design [7] comprises 32 chromatographic runs carried out in two blocks
(power
>
80 and 95%confidence interval). The
1, 0, and 1 designations refer to the low, center-point, and high
end of the range, respectively, for each of the four input variables tested.
2
1
selected to detect nonlinear effects, secondary interactions between variables, and allow
for independent estimation of the effect of each input variable on the response [7]. Two of
the input parameters tested, harvest pH and chaotrope concentration during the first
intermediate column wash, have a significant influence on CHOP levels in the capture
column eluate. The remaining two parameters, column load and elution linear velocity,
affect the column elution volume.
The outcome of these experiments indicates the optional use of a high-concentration
(4M) chaotrope intermediate wash step during the operation of the rPA capture column.
