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Characterization of Phyto-Constituents
Published in Rohit Dutt, Anil K. Sharma, Raj K. Keservani, Vandana Garg, Promising Drug Molecules of Natural Origin, 2020
Himangini, Faizana Fayaz, Anjali
GC-MS is the aggregate of two effective device Gas spectrometry and Mass chromatography which is the most delicate and particular method and gives data on the molecular weight as well as the compound structure. In MS, it depends upon ionization of molecule and then separate the ions. The methods of ionization integrated with GD are electron impact (EI) and electron capture ionization (ECI) method. Electron Ionization specifically pulls in towards positive ions, while ECI is utilized for negative ions (ECNI).
GC-MS Analysis of Methanolic Extract of Rubus ellipticus
Published in Parimelazhagan Thangaraj, Phytomedicine, 2020
Elizabeth George, Blassan P. George, Sajeesh Thankarajan, Parimelazhagan Thangaraj, Kasipandi Muniyandi, Saikumar Sathyanarayanan
GC-MS analysis was carried out using a Clarus 600 gas chromatograph system equipped with a Clarus 600 C mass spectrometer (PerkinElmer Precisely, USA). An Elite-5MS fused silica capillary column coated with a 5% diphenyl/95% dimethyl polysiloxane stationary phase was used for the GC/MS. The injector temperature was kept at 200°C, whereas the oven temperature was programmed from 70°C to 300°C for a total run time of 35 minutes. Helium was used as the carrier gas at a flow rate of 1.0 mL/min, and the solvent delay was fixed to 4 minutes after running a blank. The following parameters were set for the MS analysis: electron ionization mode with ionization energy of 70 eV; ion source temperature of 200°C; GC interface temperature of 240°C; scan interval of 0.2 second; and fragments range from 50 to 600 m/z. About 1 µL of the methanol extract of the R. ellipticus fruit was injected manually in a splitless mode. The mass spectra of the respective peaks obtained in the GC/MS were compared with the mass fragmentation patterns of standards in the National Institute of Standards and Technology library.
Emerging Biomedical Analysis
Published in Lawrence S. Chan, William C. Tang, Engineering-Medicine, 2019
Hard ionization is a process that imparts sufficient internal energy to induce fragmentation of analyte molecules. Hard ionization sources generate in-source ion fragments, which provide the chemical structure information for the molecules of interest. This feature makes hard ionization approaches suitable for elemental analysis and small molecule analysis. Common examples of hard ionization are electron ionization (EI) and inductively coupled plasma (ICP).
Amorphization and modified release of ibuprofen by post-synthetic and solvent-free loading into tailored silica aerogels
Published in Drug Delivery, 2022
Ajmal Zarinwall, Viktor Maurer, Jennifer Pierick, Victor Marcus Oldhues, Julian Cedric Porsiel, Jan Henrik Finke, Georg Garnweitner
To elucidate the coordination mode of the ligands, thermogravimetric analysis (TGA; STA7200, Hitachi High-Tech Analytical Science, Oxford, UK) was linked with mass spectrometry (GSD 320 Thermostar TM, Pfeiffer-Vacuum, Asslar, Germany) via a coupling device (280 °C, REDshift, San Giorgio in Bosco, Italy). 10–12 mg of the samples were measured in alumina crucibles at a heating rate of 10 K/min in a nitrogen flow of about 200 mL/min up to 600 °C. The flow was redirected into a heated transfer capillary (deactivated fused silica tubing; inner diameter: 0.15 mm; outer diameter: 0.22 mm; kept at 280 °C; split of 1:200) and the coupling into the inlet (150 °C) of the mass spectrometer. The mass spectrometer was operated in the electron ionization mode at 70 eV with a secondary electron multiplier at 1080 V as detector. Measurements were performed in multiple-ion detection mode (MID) with 200 ms measurement time. The measured ion currents I(T) were baseline-corrected to their minimum Imin and normalized to the weight of the sample msample to obtain comparable ion currents Irel(T) according to:
In vitro and in silico β-lactamase inhibitory properties and phytochemical profile of Ocimum basilicum cultivated in central delta of Egypt
Published in Pharmaceutical Biology, 2022
Nagwa A. Shoeib, Lamiaa A. Al-Madboly, Amany E. Ragab
The GC–MS is the most suitable technique for qualitative and quantitative characterization of the compounds of essential oils (Mesaros et al. 2009). A Thermo Scientific, Trace GC Ultra/ISQ Single Quadrupole MS (Waltham, MA) was used for the GC/MS analysis using a TG-5MS fused silica capillary column (30 mm, 0.25 mm, 0.25 mm film thickness). An electron ionization system with ionization energy of 70 eV was used for GC–MS detection. The carrier gas was Helium that used at a constant flow rate of 1 mL/min. The injector and MS transfer line temperature was set at 280 °C. The oven temperature was programmed at an initial temperature 40 °C (hold 3 min) to 280 °C as a final temperature at an increasing rate of 5 °C/min (hold 5 min). Identification of the compounds was performed based on the comparison of their retention index (RI) calculated with reference to a homologous series of n-alkanes (C8–C25) to that published in the literature, retention time (Rt) and mass spectra with those of the NIST, WILLY library data of the GC/MS system. The RI was calculated using the Kovats retention index equation. The quantification of all the identified components was performed using a percent relative peak area.
Phytochemical constituents and protective efficacy of Schefflera arboricola L. leaves extract against thioacetamide-induced hepatic encephalopathy in rats
Published in Biomarkers, 2022
Ali M. El-Hagrassi, Abeer F. Osman, Mostafa E. El-Naggar, Noha A. Mowaad, Sahar Khalil, Manal A. Hamed
The n-hexane fraction of Schefflera arboricola L. leaves was analyzed using Thermo Scientific GC-MS equipped with AS 3000 autosampler, trace ultra GC, and ISQ detector. A non-polar column consisting of 5% phenylpolysilphenylene siloxane (Thermo Scientific TR 5MS) with dimensions of 30 m × 0.25 mm (internal diameter) × 0.25 µm (film thickness) was used for separation of the components. Helium, at a flow rate of 1 mL/min (constant flow mode), was used as carrier gas. A volume of 2 µL of sample extracts was injected in splitless mode. The injection port was set at 260 °C and the temperature of the oven was initially set at 50 °C for 2 min. Then it was ramped to 140 °C at the rate of 5 °C/min for 2 min and finally to 280 °C at the rate of 3 °C/min for 50 min. The maximum oven temperature was set at 330 °C. The mass spectrometer was operated in an electron ionization (EI) mode within the mass range of 50–700 amu with 20 scan times (min). The MS transfer line temperature and ion source temperature were kept at 290 and 300 °C, respectively with an electron multiplier voltage of 1 Kv. The mass spectra were interpreted using the reference library of the National Institute of Standards and Technology (NIST), US, along with Willey 5 and mass finder. The constituent percentages were measured based on the peak area.