Biomembrane-Inspired Plasmonic Superstructures with Phenolic-Resin Artificial Pockets for Enantioselective...

Area of Science:

• Nanotechnology
• Analytical Chemistry
• Biochemistry

Background:

• Chiral discrimination of amino acid enantiomers is crucial for pharmaceuticals and biomarkers.
• Surface-enhanced Raman spectroscopy (SERS) faces challenges in enantioselective sensing due to spectral similarity and analyte localization.

Purpose of the Study:

• To develop a ligand-free chiral SERS discrimination strategy using advanced plasmonic superstructures.
• To enhance sensitivity and selectivity for amino acid enantiomer analysis.

Main Methods:

• Fabrication of SiO2@Au@RF plasmonic superstructures with porous resorcinol-formaldehyde (RF) shells and 3D gold (Au) hotspot amplifiers.
• Utilizing cooperative noncovalent interactions and differential adsorption kinetics within RF nanochannels for chiral recognition.
• Employing confined seed-mediated growth to create a dense 3D Au hotspot matrix for enhanced SERS signals.

Main Results:

• The superstructures demonstrated pronounced discrimination between l- and d-tryptophan.
• Achieved a linear calibration for enantiomeric excess determination.
• Showed successful extension to other amino acid pairs like histidine, arginine, and glutamine.

Conclusions:

• The developed plasmonic superstructures offer a distinct strategy for ligand-free enantioselective SERS sensing.
• This approach expands the capabilities for practical chiral analysis, particularly for amino acid enantiomers.