Meng Xin,Zong Hou,Zheng Zhong,Xing Junpeng,Liu Zhiqiang,Song Fengrui,Liu Shu
α-Glucosidase inhibitors in natural products are one of the promising drugs for the treatment of type 2 diabetes. However, due to the complexity of the matrix, it is challenging to comprehensibly clarify the specific pharmacodynamic substances. In this study, a novel high-throughput inhibitor screening strategy was established based on covalent binding of α-glucosidase on chitosan-functionalized multi-walled carbon nanotubes coupled with high-resolution mass spectrometry. The synthesized MWCNTs@CS@GA@α-Glu was characterized by TEM, SEM, FTIR, Raman, and TG. Performance studies showed that the microreactor exhibited stronger thermostability and pH tolerance than that of the free one while maintaining its inherent catalytic activity. Feasibility study applying a model mixture of known α-glucosidase ligand and non-ligands indicated the selectivity and specificity of the system. By integrating ultra-high-performance liquid chromatography-tandem mass spectrometry (UHPLC-QTOF-MS) with ion mobility mass spectrometry (IMS), 15 ligands were obtained and tentatively identified from Tribulus terrestris L., including 8 steroidal saponins, 4 flavonoids, and 3 alkaloids. These inhibitors were further validated by in vivo experiments and molecular docking simulation.
Yang Jingxuan,Guo Wenjun,Xu Xiaohang,Zhao Liang,Xu Yajuan,Wang Yang
Fatty acids (FAs) are an important class of functional small molecules and participate in a variety of life biological processes. This experiment proposed a liquid chromatography–quadrupole-Qrbitrap mass spectrometry (LC–Q-Orbitrap MS) method to perform FA profiling under parallel reaction monitoring (PRM) acquisition mode. The FA was derivatized by 2-dimethylaminoethylamine (DMED) to increase the ionization efficiency and provide the characterized fragment pattern. The mass spectra obtained from full scan, multiple ion monitoring (MIM), and PRM were compared. The results showed that the protonated ion of FA + DMED–H 2 O was detected and the neutral loss of 45.06 Da was observed in the tandem mass spectrum. The PRM method provided the highest selectivity and sensitivity for FA detection with the help of accurate mass weight and specific neutral loss-based fragments. The method validation was performed using the FA standards and pooled quality control serum sample, which showed that the established method had good repeatability, stability, and linearity. Finally, the developed method was successfully applied to analyze the rat serum and brain tissue samples for the drug efficacy evaluation of gross saponin of Tribulus terrestris L. fruit (GSTTF) against middle cerebral artery occlusion (MCAO)-induced ischemic stroke. This method has extensive practicability and great potential in the detection of FA, especially for the analysis of samples with complex matrices.
危险品化学品经营许可证（带存储）