Rapid identification of bacteria direct from a blood culture bottle would speed patient treatment and recovery and greatly reduce hospital care costs. The current procedure of subculturing typically takes from 24 to 48 hours to obtain bacterial identifications. Gas chromatographic analysis of bacterial fatty acids has promise as a rapid and inexpensive identification technique if the system were made more sensitive and if impact of the fatty acid composition of the blood could be minimized. Splitless injection of the entire fatty acid extract and use of an electron capture detector may increase the chromatographic sensitivity by a factor of ca. 6,000,000X. Physical separation of bacteria from blood components by gradient centrifugation and/or filtration and the use of software techniques for reducing the impact of blood fatty acid components will be researched. New algorithms for naming bacteria and for dealing with polymicrobic cultures will be evaluated. By producing identification more rapidly than current techniques, the proposed technique could save ca. $1,000 per patient day of care costs where blood cultures are taken. By speeding treatment and recovery, this technique will also reduce patient suffering and aid in reducing nosocomial infections. PROPOSED COMMERCIAL APPLICATIONS: Identification of bacteria direct from a blood culture bottle will save at least one day by assuring speedy treatment of patients with septicemia thereby reducing medical care costs. MIDI will sell the software, gas chromatograph and consumables related to this application and will develop other applications based on the technique.