Abstract：
A novel method for chiral identification of glutamine enantiomers based on chiral carbon quantum dots (cCQDs) fluorescent probes. cCQDs were prepared using a one-step hydrothermal method with L-tryptophan as the carbon source and chiral source, producing spherical nanoparticles exhibiting a blue colour luminescence. The fluorescence intensity (F) of cCQDs was enhanced or quenched following the addition of chiral enantiomeric glutamine (L/D-Gln), and therefore cCQDs, as a fluorescence probe, could be used for enantioselective sensing of the L/D-Gln. The fluorescence enhancement value (∆FE ) exhibited good linearity with L-Gln concentration in the range 0.23-10.00 mM, and the limit of detection was 0.14 mM. The fluorescence quenching value (∆FQ ) showed a good linear relationship with D-Gln concentration in the range 0.29-10.00 mM, and the detection limit was 0.18 mM. The mechanism of fluorescence enhancement/quenching was explored by molecular modelling and the type of quenching. The method was applied to the determination of L-Gln content in real samples, and the recovery rate was satisfactory. This study provided a novel approach for the synthesis of cCQDs and the recognition of amino acid enantiomers.
摘要：
基于手性碳量子点(cCQDs)荧光探针的谷氨酰胺对映体手性鉴定新方法.以L-色氨酸为碳源,手性源,采用一步水热法制备cCQDs,产生呈现蓝色发光的球形纳米颗粒。添加手性对映体谷氨酰胺(L/D-Gln)后，cCQDs的荧光强度(F)增强或猝灭，因此，cCQDs，作为荧光探针，可用于L/D-Gln的对映选择性传感。荧光增强值（ΔFE）与L-Gln浓度在0.23-10.00mM范围内表现出良好的线性，检测限为0.14mM。荧光猝灭值(ΔFQ)在0.29-10.00mM范围内与D-Gln浓度呈良好的线性关系,检出限为0.18mM。通过分子模型和猝灭类型探索了荧光增强/猝灭的机理。该方法用于实际样品中L-Gln含量的测定。回收率令人满意。本研究为cCQDs的合成和氨基酸对映体的识别提供了新的途径。
