Pathogen Detection Using Headspace Analysis

The ability to rapidly screen samples for the presence of pathogens offers many advantages. From a security standpoint, the rapid classification of samples as pathogenic or non-pathogenic (suspicious powders, for example) can elicit a more rapid first response and can minimize the labor intensive processing of countless samples in the laboratory, thus saving both time and money. In a clinical setting, pre-symptomatic diagnosis of infection can prevent the onset of life-threatening illnesses, speed up treatment of infection, and eliminate the unnecessary or inappropriate prescription of antibiotics. The variation in volatile metabolic byproducts produced by bacteria provides a signature with which to identify infectious agents. Analysis of the volatile constituents affords an orthogonal means of identification that can be performed in conjunction with the commonly used PCR and antibody tests. Our research has focused on optimizing and simplifying headspace collection techniques to enable reliable sampling of volatile compounds from both liquid and solid samples. We have also established noninvasive breath-sampling techniques that will allow individuals to be monitored for pre-symptomatic diagnosis of infection. Using thermodesorption gas chromatography-mass spectrometry (GC-MS), the gas-phase signatures of potential threat-agent bacteria and causative agents of respiratory infections have been examined under a variety of conditions. Initial results from this study indicate that headspace signatures provide a means of detection and discrimination that can be applied toward the development of small portable sensors for use in either field or clinical settings. See also ADM001849. Presented at the Scientific Conference on Chemical and Biological Defense Research 2004 held in Hunt Valley, MD on 15-17 Nov 2004. Pub. in the Proceedings of the Scientific Conference on Chemical and Biological Defense Research p2-16, 2004.