ABSTRACT
The Threshold Immunoassay System is sold commercially as a sensitive, reliable analytical system used for quantitative determination of various solution analytes [1,2]. It is currently utilized by the pharmaceutical indus try for the detection of impurities in the production of biopharmaceuticals by companies seeking FDA approval for the release of their products [3-7]. These contaminants include DNA and host cell proteins, which are often present in genetically engineered products. Furthermore, testing for column material such as protein G (or A) used in the monoclonal antibody purifica tion process is also necessary [3,7,8].
