(545a) Cell-Based, Non-Invasive Sensing of Inhalation Health Hazards

Public concern for the risks associated with inhalation hazards has been raised due to several highly-publicized cases of exposures to anthrax, combustion wastes, and indoor air pollution. Epidemiological studies have demonstrated that increases in exposure to airborne PM, particularly in heavily urbanized areas, correlates with increases in cases of emphysema, pulmonary inflammation, chronic bronchitis, and asthma. The lack of rapid methods to directly quantify the health impact of suspected inhalation hazards limits our ability to provide practical, continuous monitoring especially for homeland security applications. Continuing needs focus on both detection and identification of hazards.

The goal of this research is to develop biological sensing methods based on use of orthogonal methods to characterize the response of cells and tissues to toxins and stresses quantified through several non-invasive methods. Toxins include inhalation hazards that are characterized as cytotoxic compounds that damage cell membranes, genotoxins that alter nucleic acids, microbial toxins, and viruses. Our work focuses on the use of several types of spectroscopy from Infrared to Raman that can be utilized to monitor the response of living lung cells to various hazardous compounds.

Cellular infrared spectroscopy is particularly well suited to evaluate damage to cell membranes as a result of exposure to surface-binding agents including cytolysins that bind to membrane cholesterol. Rapid changes in membrane integrity are observed after as little as 5 minutes of exposure to some membrane damaging agents as determined by a fiber delivered infrared spectroscopic measurement. Other toxins that damage additional cellular components present an array of altered spectral features which can be used to provide an initial screen for hazard identification. The challenges of maintaining cells in a native-like environment will be addressed.