The long term objective of this project is to develop a novel diagnostic testing methodology that can increase the safety and volume of the blood supply. The basis for this method is an innovative amplification technology called BRIDGE. BRIDGE allows for the simultaneous detection of a plurality of organisms or cellular antigens in a single assay. The simplicity and sensitivity of BRIDGE will allow more extensive screening while reducing the overall cost of testing (currently at $10 $25 per unit of blood). In this Phase I study, Dr. Bing will determine the feasibility of this concept using a simple model system. A single amplification reaction will be used to detect bacterial contamination in platelet concentrates and classify the bacterial load as gram positive or gram negative. Successful completion of this study should demonstrate the following critical feature of BRIDGE: Multiple amplifications can be performed using distinct primer DNA pairs, immobilized to select pixels of an array. Immobilized primers and amplification products facilitate detection and automation while significantly reducing labor costs. Dr. Bing envisions an automated test system that can screen blood for virus and bacteria, as well as type for red cell and platelet antigens in a single test.