Xiao-Lin Xie,Zhao Zhang,Wen Xiong,Jie Wang,Wei Gong,Wen Xu,Shuang Cai,Jing Li
Carbon dots (CDs) prepared from biomass usually produce poor quantum yield and reproducibility. A fine separation of raw materials may enhance the fluorescence performance. In this work, embryos of cumin seeds were precisely chosen as the carbon source to prepare (CDs) through hydrothermal method. The obtained product (CDs-E) possessed a higher quantum yield of 10.60 % than those synthesized with testas or whole seeds, which may be due to the relatively smaller particle size and more C-N functional groups. Rutin, as a common natural active component, could quench the fluorescence of CDs-E notably through internal filtering effect. Herein, a highly selective fluorescent sensor based on CDs-E for detecting rutin was proposed with a linearity range of 0.05 ∼ 30 μM and a detection limit of 0.015 μM obtained. Additionally, the developed method was successfully applied for the detection of rutin in Flos Sophorae , rutin tablets and capsules. This work showed the significance of fine classification for natural carbon source in preparation of CDs and provided a feasible method for quality monitoring of rutin-related pharmaceuticals, health care products and traditional Chinese medicinal materials.
Dandan Li,Xinxing Jiang,Yaxue Zhang,Wenxia Xue,Jihong Fu
A novel approach based on polydimethylsiloxane/graphene oxide/deep eutectic solvent (PDMS/GO/DES) sponge headspace solid phase extraction followed by GC-MS was successfully developed to determine the volatile components in cumin. The PDMS/GO/DES exhibits outstanding properties with high adsorption capacity and good chemical stability, and has shown its potentiality as an ideal adsorbent for the extraction of volatile compounds. The influence factors of the extraction process were investigated. Excellent analytical performances were achieved, including wide linearity (0.60–107.72 ng) with high correlation coefficients (R2 ≥ 0.9951), low LODs (0.23–9.23 ng) and LOQs (0.54–18.47 ng), satisfactory precision (intra-day RSDs ≤ 2.85% and inter-day RSDs ≤ 3.92%). Under the optimal extraction conditions, the volatile components in 17 cumin samples from four origins in Xinjiang were analyzed and 31 compounds were identified. PCA was used to establish the relationship between the origins and the volatile compounds for further discriminant analysis. The results showed that the PDMS/GO/DES method was a rapid, simple and sensitive technique for the analysis of volatile components in spices.