The technological innovation described here is a method to visually detect and identify viable pathogenic microorganisms in human samples, using a method being developed that amplifies a biological signal by tandem enzyme catalysis.  The method consists of four main parts: antibodies, antigens, biotinylated antibodies, and biotinylated/streptavidin labeled antibodies. The hypothesis is, that if tandem enzyme catalysis in a microtiter plate (or individual sample location) containing modified enzymes, can be distinguished from wells that does not have enzymes, then sequential signal amplification via a vast number of well-known chemical, biochemical, and/or physical methods will lead to visual detection, with a possible identification dynamic range from a micro to sub-zepto mole range. The long term goal of this project is to develop a simple, fully functional detection and identification system that is capable of identifying infectious microorganisms from low concentration samples, in a single step. In addition, this system could be applied to the detection and identification of biomarkers in blood or exhaled breath, and for the detection of toxic industrial compounds, or environmental toxins.