Journal of Chromatography & Separation Techniques
Open Access
ISSN: 2157-7064
+44 1300 500008
ISSN: 2157-7064
+44 1300 500008
Xin Xiang Zhang
Peking University, China
Scientific Tracks Abstracts: J Chromatogr Sep Tech
Labelling strategy plays an important role in mass spectrometry (MS) based glycan analysis due to the high hydrophilicity and low ionizationefficiency of glycans. We designed ten hydrazino-s-triazine based labelling reagents were synthesized under facile and controllable conditions for highly sensitive LC or CEâ��electrospray MS. Attached to N-glycans through nonreductive reactions, these new labelling reagents were evaluated in differently enhanced glycan response to MS. Three of them demonstrated to be reliable and remarkable for glycan analysis with satisfactory linearity and lowered limits of detection using maltoheptaose(DP7) as model. An innovative stable-isotope relative quantification strategy for N-glycans was achieved using these non-reductive hydrazino-s-triazine deuterated derivative as a labelling reagent combined with MS also. As much as a 20 Da mass shift could effectively distinguish different forms of Nglycans labelled with normal and heavy hydrazino-s-triazine at the reducing end. Especially for glycans with high molecular weight, qualitative identification could be significantly simplified on account of avoiding isotopic distributions overlapping in LC-MS or CE-MS. Furthermore, the most optimal labelling reagent was taken as an example for highly sensitive profiling of N-linked glycans both cleaved from chicken avidin and glyco- proteins in human serum, indicating prospective availability for these labelling reagents in frontier of glycomics researches. These reagents have been applied in the determination of trace amount of organic acids in environmental samples with highly sensitivity also. In recent years because of increasing resistance and regulations on the use of antibiotics in animal feed, plant extracts have gained a lot of attention as an effective substitute to antibiotic growth promoters in animal nutrition. Researchers are very much interested in extracts of turmeric, capsicum, cinnamon among others because of their antimicrobial properties as reported in different in vitro studies. In order to have a specific effect, is of great importance to know the concentration of the raw materials. The aim of the study was to develop and validate an efficient and effective RP-UPLC method for quantification of different capsaicinoids (Nordihydrocapsaicin-NDHC, Capsaicin-CAP and Dihydrocapsaicin-DHC) from different microencapsulated samples. The ultrasonic extraction method was used for the extraction of these compounds. The reversephase UHPLC-MS analysis was carried out using an Acquity UPLC BEH C18 1.7 �¼m (2.1x50 mm) column and a mobile phase comprising of water-acetonitrile (57:43, v/v) both acidulated with formic acid 0.1% at a flow rate of 0.4 ml/min. The detection and quantitation of NDHC, CAP and DHC were carried out at 294, 306 and 308 Daltons respectively on the mass detector. The limits of detection (LOD) were 45, 115 and 55ng/ml for NDHC, CAP and DHC, respectively. Detector response was found to be linear from 100 to 2500, 400-4000 and 100 to 3500 ng/ml for NDHC, CAP and DHC respectively. The present method provides an efficient, accurate and highly reproducible method for quantification of different capsaicinoids in different microencapsulated samples and oleoresins.
Xin Xiang Zhang has been working in the field of capillary electrophoresis for over 20 years. He has founded a serious high sensitive determination of small bioactive compounds by CE combined with affinity extraction procedures. The improvement and application of sheathless interface for CE-MS is focus of his research in recent years. With the new designed labelling reagents, the glycan profiling especially the differential glycan profiling can be achieved by CE-MS and/or LC-MS.