Department of Chemistry, Northeast Agricultural University, Harbin 150025, China.
Department of Physiology, Hei Longjiang University of Chinese Medicine, Harbin 150040, China.
Molecules. 2019 Nov 15;24(22):4136. doi: 10.3390/molecules24224136.
In this paper, we designed a new quantitative and qualitive detection method for biothiols by using fluorescence method and resonance light scattering (RLS) technique. Nitrogen doped carbon quantum dots (C/N-dots) were obtained from tartaric acid and ethylenediamine by hydrothermal method, and then their morphology and optical properties were characterized by different techniques. A detection system consisting of C/N-dots and Ag complex was established. In this system, C/N-dots possessed the photoluminescent property and the Ag complex owned the RLS property, so, by combining the two luminescent properties to achieve complementary advantages, we could detect biothiols and solve the problem of distinguishing between Cys and GSH. Additionally, we optimized detecting conditions and investigated the detection mechanism of fluorescence quenching and RLS detecting. Results showed that the analytical response of fluorescence was linear in the range 0-140 μM and the detection limit (LOD) was calculated to be 6.6 μM for Cys, and the addition of GSH had no effect on fluorescence. RLS response ranges were 0-167 μM for Cys and 0-200 μM for GSH, with LOD down to 64 nM and 74 nM, respectively. Furthermore, the probe was successfully used for detecting Cys in fetal bovine serum (FBS) samples by fluorescence method, and also, by RLS technique, the content of GSH in FBS samples was detected.
本文设计了一种新的定量和定性检测生物硫醇的方法，采用荧光法和共振光散射（RLS）技术。通过水热法从酒石酸和乙二胺中得到氮掺杂碳量子点（C/N-dots），并用不同的技术对其形貌和光学性质进行了表征。建立了一个由 C/N-dots 和 Ag 配合物组成的检测系统。在这个系统中，C/N-dots 具有荧光性质，Ag 配合物具有 RLS 性质，因此，通过结合两种发光性质以实现互补优势，我们可以检测生物硫醇并解决区分半胱氨酸和谷胱甘肽的问题。此外，我们优化了检测条件，并研究了荧光猝灭和 RLS 检测的检测机制。结果表明，荧光分析响应在 0-140μM 范围内呈线性，对半胱氨酸的检测限（LOD）计算为 6.6μM，而谷胱甘肽的加入对荧光没有影响。RLS 响应范围分别为 0-167μM 的半胱氨酸和 0-200μM 的谷胱甘肽，LOD 分别达到 64nM 和 74nM。此外，该探针成功地用于通过荧光法检测胎牛血清（FBS）样品中的半胱氨酸，并且还通过 RLS 技术检测了 FBS 样品中的谷胱甘肽含量。
