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Abstract The identification of Chiral molecules is essential in pharmaceutical and food science. However, conventional methods are complex and cost‐prohibitive. This study introduces a sustainable method using hydroxypropyl cellulose (HPC) gel to identify amino acids enantiomers, such as phenylalanine and alanine, through visible light. By integrating the structural color properties of HPC, this research demonstrates the HPC gel's capability to distinguish L (Levo)‐phenylalanine (L‐Phe), D (Dextro)‐phenylalanine (D‐Phe), and DL (racemic mixture)‐phenylalanine (DL‐Phe) supplemented with visible circular dichroism (CD) spectra or hydrochloric acid (HCl) as visual indicators. Similar chiral sensing results are observed with D‐alanine, L‐alanine, and DL‐alanine. Unlike traditional UV‐based detection requiring expensive equipment, this approach simplifies the process while maintaining sensitivity. Varying phenylalanine concentrations altered the CD response without disrupting the gel's helical structure, and color changes in response to HCl addition facilitated visual identification of enantiomers. Furthermore, adding various salts generates colorful HPC/Phe gels, demonstrating their suitability for 3D printing. Meanwhile, the HPC gels remained functional for three months, indicating long‐term stability. These advancements are significant for pharmaceutical and biotechnological industries, facilitating efficient low‐concentration chirality detection (0.2 wt.%). Continued development and refinement of this technology are expected to expand its applications and improve analytical capabilities for future chirality‐related studies and photonic gel 3D printing.
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This content will become publicly available on April 21, 2026
Origin of Intrinsic Chirality in Cysteine‐Passivated Metal Halide Perovskite Nanoclusters
Ligand‐assisted perovskite nanoclusters (PNCs) have been synthesized using oleylamine and L‐ or D‐cysteine as confirmed based on their characteristic electronic absorption bands around 430 nm based on ultraviolet‐visible spectra. Circular dichroism (CD) spectra show distinct chiroptical bands in the 430–440 nm region, revealing the chirality of the PNCs. Interestingly, the sign of the CD signal is always negative, independent of the chirality for L‐ or D‐cystine. This 430–440 nm CD band is tentatively attributed to the formation of new chiral stereocenters within the PNCs with an uneven ratio of two enantiomers induced by the asymmetric liquid–liquid interface from the solvent and antisolvent used during synthesis.
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- Award ID(s):
- 2203633
- PAR ID:
- 10612553
- Publisher / Repository:
- Wiley Blackwell (John Wiley & Sons)
- Date Published:
- Journal Name:
- ChemPhysChem
- Volume:
- 26
- Issue:
- 13
- ISSN:
- 1439-4235
- Format(s):
- Medium: X
- Sponsoring Org:
- National Science Foundation
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