Compact Chemical Sensor for Measurement of Internal Dose of Environmental Agents

DESCRIPTION (provided by applicant): Detection of exposure to environmental agents by measurement of internal dose of such agents or their metabolites, chemical or biological, requires rapid assessment and identification of exposure to both known and unknown threats. Fast detection and identification of exposure to such threats can provide prompt warning of the extent and severity of the exposure and save many lives by enabling and adopting protective measures. The ideal detection device is one that is small, portable, easy to use and capable of rapid analysis in the field. The levels of toxicants should be easily obtained from a convenient biosample (blood, urine, etc) for rapid determination of the internal dose of the agent, with a minimum of false positives and false negatives to avoid wasting resources and missing actual exposure problems. We propose to build a portable, field- deployable blood test monitor to immediately identify toxic chemical agent buildup in persons suspected of having been exposed to such agents. The technology we plan to utilize is surface-enhanced Raman scattering, based on a well-known inelastic laser light scattering analytical technique for precise lab identification of organic compounds to look for the presence of environmental agents directly as trace contaminants in the bloodstream (or, potentially, in urine or saliva samples, as well). The proposed system is comprised of a low- resolution Raman detection unit coupled to a strip reader that analyzes a drop of blood placed on a gold sol-gel strip. The low-resolution surface-enhanced Raman spectrum (SERS) obtained from the blood drop on the strip is compared with a spectral peak library in the unit for analysis of the presence and concentration of specific chemical components present in the patient's blood. In overview, the unit operates much like a commercial handheld glucose meter and other at-home test kits for individual blood analytes, well known for home diagnosis of patient glucose levels, but now set up for analysis of a range of blood analytes in a single device. PUBLIC HEALTH RELEVANCE: The Company believes significant markets exist for portable, field-deployable products for on-site blood analysis based on the designs created and tested in the present SBIR program. As a practical example, the Company anticipates that persons taking prescription medications that require regular monitoring for effective dose level may benefit from the present Raman approach. In this application, the drug or its metabolite might be monitored in a blood sample by SERS at regular intervals at home for compliance and adjustment of the medication, as required.