Table 3: Effect of centrifugation time on the non-protein permeate refractive index of plasma.
|
Time (min) |
Permeate (g) a) |
nD20 permeate a) |
Permeate total (g) |
nD20 total (calculated) |
net nD20 b) |
Protein (mg/mL) c) |
Relative error d) |
|
5 |
0.415 |
1.33483 |
0.415 |
1.33483 |
0.01132 |
58.4 |
0.00% |
|
12 |
0.511 |
1.33488 |
0.926 |
1.33486 |
0.01129 |
58.2 |
-0.24% |
|
22 |
0.554 |
1.33498 |
1.480 |
1.33490 |
0.01125 |
58.0 |
-0.65% |
|
37 |
0.536 |
1.33511 |
2.016 |
1.33496 |
0.01119 |
57.7 |
-1.13% |
|
60 |
0.475 |
1.33528 |
2.491 |
1.33502 |
0.01113 |
57.4 |
-1.68% |
Remark: a) The column “Permeate (g)” shows the incremental weight of permeate obtained at the given ultrafiltration times, while the column “nD20 permeate” givens the corresponding RIs determined; b) The net nD20 value was calculated as the difference between the values determined for the plasma sample before starting the ultrafiltration (nD20 = 1.3461) and at the given ultrafiltration times; c) The protein concentration of the plasma was calculated for the different ultrafiltration times; d) The relative error was calculated as the percent deviation from the plasma protein concentration determined after 5 min ultrafiltration.