A dual-stage system and methods for using the same include first and second
filtration cartridges is provided and is particularly suited for
hemodiafiltration and/or hemodialysis. As fluid enters the first
diafiltration cartridge, the hydrogenion concentration (pH) is reduced by
exposing it to an acidic solution such as citric acid across a filter
membrane. This stage allows for improved removal of certain toxins in the
fluid, such as protein-bound substances that disassociate more readily
from proteins at lower pH. As the filtered fluid enters the second
filtration cartridge, the pH of the fluid is restored to normal levels
prior to infusion to a patient.
