SERS-active absorbers for the analysis of analytes
Solid-type SERS-active substrates (e.g., noble metallic nanostructured powders or noble metallic nanoparticle-coatings on beads, microbeads, particles, etc.) are contained within optically-transparent modules. The modules allow for the controlled introduction of analyte-bearing fluid(s) into SERS-active substrates. The modules also allow for the monitoring of SERS signals emanating from analyte(s) which have accumulated on the confined SERS-active substrates. These SERS signals may be monitored over time by direct readout of the SERS substrates through the optically transparent module for chemical analysis and chemical detection applications.
1. A system comprising:
a plurality of sealed testing modules automatically indexed to a test position such that when a module is indexed to the test position, analyte-bearing fluid flows through the module for optical SERS interrogation, and at completion of interrogation a new module is indexed into the test position; wherein,
each module comprises a capillary tube containing SERS-active nanoparticles;
each module is sealed by an inlet septum and an outlet septum before the module is indexed to the test position; and,
the septa of a module in the test position are opened to allow fluid flow through the module.
2. The system of claim 1 wherein the plurality of sealed testing modules are indexed by a rotatable carousel.
3. The system of claim 1 wherein the plurality of sealed testing modules are indexed by a chain-driven array that pulls new modules from a feed-in reservoir of unused modules and deposits spent modules in a receiving reservoir for used modules.
4. The system of claim 1 , the fluid being in a gas phase.
5. The system of claim 1 , the fluid being in a liquid phase.
6. The system of claim 1 wherein the capillary tube comprises an integrated cylindrical lens to facilitate optical SERS interrogation of the SERS-active nanoparticles.
7. The system of claim 1 wherein the septa of a module in the test position are penetrated by retractable hollow needles.