Characterization of next-generation commercial surface-enhanced Raman scattering (SERS) substrates

Abstract

Surface-enhanced Raman scattering (SERS)-based techniques are increasingly used for Army, first responder and defense relevant applications. Commonly SERS is used for the identification and characterization chemical and biological hazards, energetic materials and medical applications. SERS, like most Raman-based techniques is an beneficial analytical method to use in theatre as it offers many distinct advantages. SERS advantages include: straightforward sample identification, little to no sample preparation requirements, applicability in many environments, freedom from water interference, ability to be used with a variety of laser sources, and specific sample spectrum directly link to vibrations within the molecule constituents of the target. Despite all of these advantages, the ubiquitous use of SERS remains challenging in part due to the lack of a commercially available reproducible, high sensitivity and uniform substrates. In this paper, we discuss the need for more reproducible and sensitive SERS substrates and report on the characterization of next-generation commercial SERS substrates. The substrates analyzed are non-optimized prototypes, and demonstrate great potential for Army relevant sensing. The next-generation Klarite substrates are designated as the 308's and 309's. Within our testing parameters, the 308 demonstrates performance up to four orders of magnitude better than the standard Klarite when measuring a common SERS active analyte. For application to biological samples, all substrates demonstrate similar performance.