Chiral fluorescent carbon dots for tyrosine enantiomers: Discrimination, mechanism and cell imaging

• Published in: Sensors and actuators. B, Chemical Chemical, 2025-01, Vol.422, p.136677, Article 136677
• Main Authors: Han, Yangxia, Kou, Manchang, Zhang, Haixia, Qiu, Hongdeng, Shi, Yan-Ping
• Format: Article
• Language: English
• Subjects: Chiral fluorescent carbon dots; Chiral recognition; Density functional theory calculations; Enantiomeric differentiation; HPLC
• ISSN: 0925-4005
• DOI: 10.1016/j.snb.2024.136677

The development of chiral analytical methods for tyrosine enantiomers, characterized by superior recognition performance and selectivity, holds significant potential for application in the biochemical and biomedical domains associated with tyrosine. Herein, a straightforward and effective strategy for tyrosine enantiomers identification and purity analysis by chiral carbon dots (CDs) fluorescence sensor were reported. The chiral CDs were designed by using L-cysteine and 2,4-diaminophenol hydrochloride through a gentle one-step synthesis strategy at room temperature. The resulting chiral CDs exhibited completely different fluorescence response to L-tyrosine and D-tyrosine, that is, L-tyrosine could enhance the fluorescence of the chiral CDs, but D-tyrosine made no difference. The fluorescent differential recognition factor for enantiomers was as high as 23.2, which was the highest be achievement to our best knowledge so far. The varying discriminatory capabilities of chiral CDs towards tyrosine enantiomers were also applicable to HeLa cells. To confirm the recognition mechanism of chiral CDs to tyrosine enantiomers, the chiral CDs-modified SiO2 stationary phase were synthesized and applied to separate the tyrosine enantiomers in reverse-phase HPLC mode. Furthermore, density functional theory was combined with the fluorescence spectroscopy and chromatographic results to verify that the recognition ability was related to the difference of weak interaction energy and Gibbs free energy between the precursor molecule of the chiral CDs and the tyrosine enantiomers. This cost-effective and highly selectivity assay not only provided a valuable tool for tyrosine enantiomers identification and purity analysis, but also delivered an important reference for the recognition and purity identification of other chiral drugs. [Display omitted] •Chiral fluorescent carbon dots (CDs) were quickly prepared at room temperature.•Chiral CDs were used to distinguish between tyrosine enantiomers.•Chiral CDs modified SiO2 was prepared to verify the chiral differentiation mechanism.•DFT was applied to confirm the chiral differentiation mechanism.•Chiral CDs were utilized for the nanobiological imaging of tyrosine enantiomers.