Chikurova, N. YuShemiakina, A. O.Shpigun, O. A.Chernobrovkina, A., V...
9页
查看更多>>摘要:A number of novel stationary phases for hydrophilic interaction liquid chromatography (HILIC) containing both amides and hydroxyl groups in the functional ligand were obtained by the multicomponent Ugi reaction on the aminated silica surface. The ligands were either attached directly to the substrate surface or spaced by 1,4-butanediol diglycidyl ether (1,4-BDDGE) as a linker. Chromatographic parameters of the obtained stationary phases were evaluated using Tanaka test and model mixtures of sugars, amino acids, and water-soluble vitamins. The adsorbent obtained by direct substrate modification by the Ugi reaction showed the increase of hydrophilicity according to the Tanaka test and high selectivity toward all the analytes with separation efficiency of up to 40 0 0 0 N/m. The separation of 9 sugars in 12 min, 7 amino acids in less than 18 min, and 7 vitamins in less than 10 min with only 10 cm long column was provided. The effect of introducing 1,4-BDDGE as a linker between the substrate surface and the ligand formed via the Ugi reaction was demonstrated and discussed.
查看更多>>摘要:Sialic acids are a group of nine-carbon N-acetylated derivatives of neuraminic acid containing a keto group at position C2 (ketononose), which play important roles in many biological processes. The simultaneous detection of free sialic acid (FSA) and total sialic acid (TSA) is always challenging due to three orders of magnitude difference. An accurate and robust chemical derivatization-based liquid chromatography-mass spectrometry (LC-MS) method was proposed here to quantify both TSA and FSA in human serum with only 1 mu L human serum consumption. The derivatization method with Girard's P (GP) reagent provided an ultrasensitive analysis of sialic acids as only [GP+SA-H2O](+) ions derivatized from SA could be detected by LC-MS. The limit of quantification (LOQ) of SA was less than 5 fg (S/N = 47), which was the most sensitive measurement published for SAs in biomatrices. In addition, no matrix effect existed after 10000-fold dilution of serum extracts. The recovery rates were in the range of 98.1-114.0% and the coefficient of variations (CV) was within 5%. The method has been successfully applied for the quantification of TSA and FSA in serums of patients with different liver diseases. The specificities of TSA and FSA for the early diagnosis of severe hepatopathies were higher than most of the lab blood test indicators with area under the curve (AUC) of 0.900 and 0.882. (C) 2022 Elsevier B.V. All rights reserved.
查看更多>>摘要:Efficient separation and preconcentration of trace harmful substances in food samples is a prerequisite for reliable analysis. Most of harmful substances with different properties coexist in the food samples, which is difficult to achieve simultaneously extraction through traditional adsorbents. In this work, a new adsorbent based on cyclodextrin- fluorinated covalent organic frameworks (CD-F-COF) was prepared. The mechanism of the CD-F-COF recognizing polyfluoroalkyl substances (PFASs) and bisphenols (BPs) were validated by molecular simulation. The CD-F-COF showed strong fluorophilic and host-guest interactions for polyfluoroalkyl substances (PFASs) and bisphenols (BPs), respectively. The CD-F-COF coated membranes were immobilized on the syringe filter and coupled with multi-channel syringe pump to achieve high-throughput sample pretreatment. After that, a sensitive analytical method for the simultaneous enrichment and determination of trace BPs and PFASs was established followed by HPLC-MS/MS. The results indicated that the limits of detection for the seven BPs and three PFASs were in the range of 0.006- 0.050 ng/g and 0.0 01-0.0 08 ng/g. This method has great potential for application in sample preparation as it can fulfill fast and high-throughput for enrichment of trace multiple targets. (c) 2022 Elsevier B.V. All rights reserved.