A biological and chemical detection system is provided that detects and identifies biological and/or chemical particulates of interest. The biological and chemical detection system comprises a collector, a first optical device, a second optical device and a processor. The collector is configured to deposit particulates drawn from a fluid stream onto a sample substrate to define a sample area. The first optical device derives first data relative to at least a portion of the sample area, which is analyzed to determine at least one field of view and/or specific target location. The second optical device then interrogates the sample area at each determined target location, e.g., using Raman spectroscopy, to produce interrogation data. The processor determines whether the sample area includes predetermined biological or chemical particulates of interest based upon an analysis of the interrogation data and triggers an event such as an alarm or message if the predetermined biological or chemical particulates of interest are identified.