Integration of Surface-Sensitive Diode Laser and Microfluidic Components for On-Chip Chemical Analysis

There is a need for simple, light-weight practical instrumentation for rapid characterization of chemical and biological analytes in the modern battlefield. Recently, a surface-sensitive diode laser (SSDL), having over 1% of the mode power in the region extending 40 nm from the laser surface has been designed and fabricated. The SSDL was capable of monitoring the deposition of absorptive films as thin as 1.2nm as well as films containing little or no absorptive material. This finding suggests that the SSDL can be used in Micro Total Analysis Systems (uTAS) as well as in both homogenous and heterogeneous immunoassay. However, there remains a need to develop reliable methods of sample introduction to the 150um by 100um sensitive region of the SSDL. This proposal suggests the development of microfluidic components capable of interfacing with the SSDL to allow automated probe deposition, analyte and probe regeneration. The innovation featured by the proposed system is the combination of a SSDL to allow automated probe deposition, analyte detection and probe regeneration. The innovation featured by the proposed system is the combination of a SSDL having intense surface optical fields with microfluidic components to provide a sensor having unparalleled sensitivity to chemical and analytes. The Phase I technical objectives include evaluation of microfluidic components and structures, fabrication of the SSDL with inlet and outlet ports, and aquisition of families of test data for use in optimization of a proof-of-concept prototype system.