Dry instant blood typing plate for bedside use

A monoclonal antibody-derived, dry blood grouping plate, based upon the simple disaccharide, trehalose, is described that is indefinitely stable at room temperature and was found to have a 99.8% accuracy when tested against a standard semiautomated assay. This plate can be used by personnel with no specific training to check the recorded A,B,O, and Rhesus blood type of potential transfusion recipients in the field and at the bedside. Trehalose-based reagents may be important for bedside testing and in developing countries where refrigeration is unreliable.