| 摘要 |
A method and apparatus for analyzing a liquid for a particular constituent when the liquid contains charged macromolecules that would interfere with the analysis. The method comprises forcing the liquid through an ion exchange medium into a reaction chamber in a manner such that substantially all of the liquid passes through the ion exchange medium and determining the presence of said particular constituent. The ion exchange medium is adapted to remove substantially all of at least one type of charged macromolecule from the liquid without removing substantially any of the particular constituent. Normally at least one reagent reactive with said particular constituent must be introduced into the liquid before the determination is made. Positively or negatively charged macromolecules, or both, can be removed from the liquid by using positive or negative ion exchange resins, or combinations thereof, as the ion exchange medium. The process is particularly effective for removal of dipolar ions, especially protein molecules, whose charge depends on the pH of the medium in which they are found. The charge on the macromolecule can then be adjusted so that the ion exchange medium can selectively remove the macromolecule without removing any of the particular constituent. |
