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Abstract Detection and identification of chiral molecules are important for pharmaceutical industry, clinical analysis, and food analysis. Here, chiral molecular sensing based on spatially selective coupling between achiral metasurface and chiral molecules is demonstrated. The designed achiral metasurface exhibits strong optical chirality and electric field with dissymmetric distribution, and chiral molecules are selectively placed over the area with large optical chirality to form the coupled metasurface-molecule system with circular dichroism (CD) response for chiral molecular sensing. The CD spectra of the metasurface coupled with pure D-alanine enantiomer, L-alanine enantiomer and their mixtures are examined. The linear relationship between the peak CD value and the enantiomeric excess is demonstrated for the detection and identification of pure enantiomers and their mixtures. Furthermore, the CD response of the coupled system shows potential for the sensing of molar concentration of chiral molecules. Moreover, the effect of spatial location of molecules on the CD response is analyzed to show potential for position sensing of chiral molecules. These results of chiral molecular sensing with achiral metasurface offer new opportunities for advancing biomolecular sensing applications.
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Chiroptical Sensing of Amines With Isatins
Isatins are extensively researched compounds with diverse applications, particularly as synthetic precursors in pharmaceutical developments. However, their use as optical probes for enantioselective sensing of chiral amines has not been explored to date. Herein, we present a novel chiroptical assay with an optimized isatin that generates strong, red‐shifted circular dichroism (CD) signals at approximately 380 nm upon ketimine formation with chiral amines. The intensity of the induced CD signal increases linearly with the enantiomeric excess of the analyte and thus allows quantitative chirality analysis. The general usefulness of this approach is demonstrated with a broad range of aliphatic and aromatic chiral amines, and by accurate determination of the enantiomeric composition of 10 samples.
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- Award ID(s):
- 2246747
- PAR ID:
- 10597982
- Publisher / Repository:
- Wiley
- Date Published:
- Journal Name:
- Chirality
- Volume:
- 36
- Issue:
- 11
- ISSN:
- 0899-0042
- Format(s):
- Medium: X
- Sponsoring Org:
- National Science Foundation
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