A 3D printed sheath flow interface for surface enhanced Raman spectroscopy (SERS) detection in flow.

Area of Science:

• Analytical Chemistry
• Spectroscopy
• Microfluidics

Background:

• Surface-enhanced Raman spectroscopy (SERS) is a powerful technique for sensitive molecule detection, particularly in aqueous environments.
• Adapting SERS for continuous flow analysis is crucial for applications in metabolomics, pharmaceuticals, and diagnostics.
• 3D printing offers rapid prototyping capabilities for developing specialized analytical devices.

Purpose of the Study:

• To develop and optimize a 3D printed flow cell for sheath flow SERS detection.
• To enhance detection efficiency and address challenges of SERS in solution using hydrodynamic focusing.
• To demonstrate the utility of the 3D printed flow cell for analyzing molecules and particles.

Main Methods:

• Fabrication of a 3D printed flow cell compatible with planar SERS substrates.
• Integration of hydrodynamic focusing to create a sheath flow for analyte confinement.
• Optimization of flow rates and analysis of SERS signals with and without sheath flow for various analytes.
• Characterization of detection efficiency using both molecules and particles.

Main Results:

• The 3D printed flow cell successfully incorporates sheath flow and hydrodynamic focusing.
• Optimization of flow rates significantly increased SERS signal intensity for diverse analytes.
• Sheath flow demonstrated a marked improvement in SERS detection efficiency compared to non-sheath flow conditions.
• The device proved effective for analyzing both molecular and particulate samples.

Conclusions:

• A novel 3D printed flow cell enables efficient online SERS detection in aqueous solutions.
• The developed sheath flow system enhances SERS sensitivity and reliability.
• This technology provides a straightforward platform for disseminating advanced SERS applications.