More than half of pharmaceutical drugs in use are chiral, necessitating accurate techniques for their characterization. Enantiomers, molecules with mirrored symmetry, often exhibit similar physical traits but possess distinct chemical and biological implications. This study harnesses the strong light‐matter interaction induced by “superchiral” light to perform Surface‐Enhanced Infrared Absorption (SEIRA) induced vibrational circular dichroism measurements in the mid‐infrared spectral region. Utilizing a nanopatterned pixelated array of achiral plasmonic nanostructures, the system allows unique identification of enantiomers and biomolecules. Tunability of plasmon resonance facilitates spectral variation of the optical chirality over a wide infrared range, enabling development of a unique chiral “barcoding” scheme to distinguish chiral molecules based on their infrared fingerprint. This simple, yet robust sensor presents a low‐cost solution for chiral mapping of drugs and biomolecules.
This content will become publicly available on February 23, 2025
The accurate detection, classification, and separation of chiral molecules are pivotal for advancing pharmaceutical and biomolecular innovations. Engineered chiral light presents a promising avenue to enhance the interaction between light and matter, offering a noninvasive, high-resolution, and cost-effective method for distinguishing enantiomers. Here, we present a nanostructured platform for surface-enhanced infrared absorption–induced vibrational circular dichroism (VCD) based on an achiral plasmonic system. This platform enables precise measurement, differentiation, and quantification of enantiomeric mixtures, including concentration and enantiomeric excess determination. Our experimental results exhibit a 13 orders of magnitude higher detection sensitivity for chiral enantiomers compared to conventional VCD spectroscopic techniques, accounting for respective path lengths and concentrations. The tunable spectral characteristics of this achiral plasmonic system facilitate the detection of a diverse range of chiral compounds. The platform’s simplicity, tunability, and exceptional sensitivity holds remarkable potential for enantiomer classification in drug design, pharmaceuticals, and biological applications.
more » « less- Award ID(s):
- 1808045
- PAR ID:
- 10558712
- Publisher / Repository:
- Science
- Date Published:
- Journal Name:
- Science Advances
- Volume:
- 10
- Issue:
- 8
- ISSN:
- 2375-2548
- Format(s):
- Medium: X
- Sponsoring Org:
- National Science Foundation
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