This chapter explains the technology behind the DxI 600 and 800 random-access immunoassay systems for a wide range of analytes. The immunoassays are based on a paramagnetic particle separation, alkaline phosphatase enzyme label and chemiluminescent signal generation. The features of the system are listed, and the design and principles explained, except for the chemistry, which is cross-referenced to the Access 2 chapter, which explains the details (7.15).

Katherine Leith is employed at Beckman Coulter in the Immunoassay and Molecular Diagnostics Division as a Senior Scientist in the Customer Technical Support group. She received a MS in Microbiology from University of Louisiana, Lafayette, and a Bachelor of General Studies from Indiana University. After her formal education, Katherine worked in clinical immunology and chemistry laboratories and conducted academic research into the role of various hormones and peptides on metabolism. She also worked for biopharmaceutical startup companies, using monoclonal antibodies for therapeutic purposes. Within Beckman Coulter, Katherine has made contributions in several areas, including Assay Development, Project Management, and Technical Training, the latter truly igniting her passion for teaching others about the elegance and nuance of immunoassays.

UniCel, DxI, Access, paramagnetic, microparticle, chemiluminescence, alkaline phosphatase, random access, competitive, immunometric, indirect, immunocapture, calibration, antibodies, separation, signal generation, signal detection, Stat.