Soft surface-enhanced Raman scattering sensing platform based on an oil-in-water emulsion stabilized by silver...

Area of Science:

• Nanotechnology
• Analytical Chemistry
• Biochemistry

Background:

• Pickering emulsions are effective platforms for biosensing applications.
• Surface-Enhanced Raman Spectroscopy (SERS) is a powerful technique for biomolecule detection.
• Silver nanoparticles (Ag-NPs) are commonly used as SERS substrates.

Purpose of the Study:

• To develop a SERS sensor using oil-in-water Pickering emulsions stabilized by Ag-NPs.
• To investigate the impact of Pickering emulsion structure on SERS signal enhancement.
• To compare the SERS performance of Pickering emulsions with colloidal Ag-NP dispersions.

Main Methods:

• Fabrication of oil-in-water Pickering emulsions stabilized by Ag-NPs.
• Adsorption of a Raman-active molecule (4-Aminothiphenol, 4ATP) onto Ag-NPs.
• Optimization of emulsion composition (water:oil ratio, Ag-NP concentration).
• Measurement and comparison of SERS signals from Pickering emulsions and colloidal dispersions.

Main Results:

• The developed Pickering emulsion (water:oil ratio 7:3, 1 wt% Ag-NPs) demonstrated a 10-fold higher SERS signal compared to colloidal dispersions.
• The enhanced SERS response was observed across various concentrations of the Raman-active molecule.
• Structural tuning of the Pickering emulsion maximized the optical response.

Conclusions:

• Pickering emulsions stabilized by Raman-active Ag-NPs provide superior SERS sensitivity for biosensing.
• This approach facilitates the detection of diverse analytes with high sensitivity.
• Utilizing Raman-active Pickering stabilizers offers significant advantages for soft biosensing devices.