Current Issue : January - March Volume : 2020 Issue Number : 1 Articles : 5 Articles
Viticis Fructus (VF) was named Manjingzi as a commonly used traditional Chinese medicine\n(TCM) targeting various pains and inflammation for more than 2000 years. To guarantee the quality of\nViticis Fructus, a simple, quick and eco-friendly Beta/ZSM-22 zeolites-based-mixed matrix solid-phase\ndispersion method (B/Z-MMSPD) was established for simultaneous extraction and determination\nof eight compounds (two phenolic acids, two iridoid glycosides, vanillin and three flavonoids)\nwith different polarities from Viticis Fructus by high performance liquid chromatography coupled\nwith a diode array detector (HPLC-DAD). Beta and ZSM-22 were mixed as the sorbent. Water,\ntetrahydrofuran and methanol were blended with certain ratio as the eluent. Several parameters\nincluding types of sorbents, mass ratio of Beta to ZSM-22, mass ratio of matrix to sorbent, grinding\ntime, types, concentration and volume of eluent were optimized. The recoveries of eight analytes were\nwithin the range of 95.0%â??105% (RSDs less than equal to 4.13%). The limits of detection and limits of quantitation\nranged from 0.5 to 5.5 microg/g and from 1.5 to 16 microg/g, respectively. Compared to the traditional\nextract methods, it was a simple, rapid, efficient and green method. The results demonstrated that a\nsimple, rapid, efficient and green B/Z-MMSPD was developed for the simultaneous extraction and\ndetermination of eight target analytes with different polarities for quality control of Viticis Fructus....
Isoquinoline alkaloids are the main group of secondary metabolites present in Chelidonium\nmajus extracts, and they are still the object of interest of many researchers. Therefore, the development\nof methods for the investigation and separation of the alkaloids is still an important task. In this\nwork, the application potential of a silica-based monolithic column for the separation of alkaloids\nwas assessed. The influence of the organic modifier, temperature, salt concentration, and pH of the\neluent on basic chromatographic parameters such as retention, resolution between neighboring peaks,\nchromatographic plate numbers, and peak asymmetry were investigated. Based on the obtained\nresults, a gradient elution program was developed and used to separate and quantitatively determine\nthe main alkaloids in a Chelidonium majus root extract....
Chromatography is widely used in biotherapeutics manufacturing, and the corresponding\nunderlying mechanisms are well understood. To enable process control and automation, spectroscopic\ntechniques are very convenient as on-line sensors, but their application is often limited by their\nsensitivity. In this work, we investigate the implementation of Raman spectroscopy to monitor\nmonoclonal antibody (mAb) breakthrough (BT) curves in chromatographic operations with a low titer\nharvest. A state estimation procedure is developed by combining information coming from a lumped\nkinetic model (LKM) and a Raman analyzer in the frame of an extended Kalman filter approach (EKF).\nA comparison with suitable experimental data shows that this approach allows for the obtainment of\nreliable estimates of antibody concentrations with reduced noise and increased robustness....
An innovative chromatographic analysis was developed for the determination of\nmoniliformin (MON). Because of its ionic nature, MON is weakly retained in reversed-phase\nchromatography and the separation may be tricky. Nevertheless, this technique is normally used\neither with the formation of ion pairs or employing specific RP columns for polar compounds, or\ncombining anion exchange and hydrophobic interactions. Hydrophilic interaction chromatography\n(HILIC) was also used, but a non-negligible peak tailing was observed. Besides its ionic nature, MON\nis a di-ketone and di-ketones, mainly Beta-di-ketones, can easily form complexes with lanthanide ions.\nThen, in this work the addition of lanthanide ions to the mobile phase was investigated, aiming at\nimproving peak shape and MON separation������....
In this study, the constituents of a Corydalis bungeana Turcz extract were qualitatively\nanalyzed using gradient elution with a mobile phase of 0.2% acetic acid and acetonitrile. We obtained\ncomprehensive insight into the constituents of C. bungeana Turcz extracts through the quantitative\nanalysis of 14 compounds by comparison with authentic reference standards, and tentatively identified\nan additional 44 compounds through electrospray ionization mass spectrometry (ESI-MS) and tandem\nMS detection. The separation was successfully achieved using an Agilent SB-C18 column (1.8 microm,\n150 * 2.1 mm; Agilent, Santa, CA, USA). A tandem quadrupole spectrometer was operated in either\nfull-scan mode or multiple reaction monitoring (MRM) for the qualitative and quantitative analyses\nof the constituents, respectively. Validation data (inter-day and intra-day combined) for accuracy and\nprecision ranged from -4.80% to 4.73%, and 0.30% to 4.97%, respectively. An ultrahigh performance\nliquid chromatographic-ESI-tandem MS (UHPLC-ESI-MS/MS) method for qualitative of C. bungeana\nTurcz (C. bungeana) extract and the quantification of 14 alkaloids, namely, A-N, was developed and\nvalidated. Quantitative analysis involved gradient elution with a mobile phase of 0.1% acetic acid\nand methanol for 45 min. The separation was successfully achieved using aWaters SB-C18 column\n(1.8 microm, 100 mm * 2.1 mm,Waters, Milford, Massachusetts, USA). The repeatability and stability of\nthe method also met USFDA criteria with CV values lower than 5%. The limit of detection of the\n14 alkaloids ranged from 9.74 to 13.00 ng/mL, whereas the linearities of the standard curves were\nbetween 0.9991 and 0.9995. In total, 15 commercial samples from 11 different sources were analyzed....
Loading....