ABSTRACT
This chapter describes the original Luminex instrumentation and later enhancements. It discusses the evolution of the bead-based multiplexing techniques employed by Luminex Corporation. One significant advantage of Luminex's real time classification, as opposed to follow-on bead-based systems, is the ability to determine when enough events have been collected to generate acceptable statistics for each analyte. Many users have found that the Luminex 100's limit of detection (LOD) can be improved in many assays by increasing the original default gain of the photomultiplier tube that collects the light from the fluorescent molecules on the bead surface. Luminex chose to develop a temperature compensation technique based on empirical measurements of a family of avalanche photo diodes with different gain of 60 bias voltages. While the LOD is improved, the ability to measure high concentration analytes accurately is impeded due to the instrument's fixed dynamic range.
