Production, Extraction and Characterization of Alginates from Seaweeds
Gokare A. Ravishankar, Ranga Rao Ambati in Handbook of Algal Technologies and Phytochemicals, 2019
Gaz Chromatography coupled with Mass Spectrometry and Electron Ionization (GC/MS-EI) is another method for determining M/G ratios of hydrolyzed alginates (trifluoroacetic acid 2 M, 90 min, 120°C) after derivatization of their constitutive uronic acids (Hentati et al. 2018). Silylation using BSTFA (Bis (trimethysilyl) trifluoroacetamide) and TMCS (trimethylchlorosilane) reagents (99:1–90:10) is the most common method used at various temperatures (from ambient temperature to 80°C) and reactions times (30 to 240 min). Trimethylsilyl-O-glycosides into dichloromethane can be separated for example into a OPTIMA-1MS column eluted with a helium flow rate (Hentati et al. 2018).
Glycerine Analysis
Eric Jungermann, Norman O.V. Sonntag in Glycerine, 2018
A report by Molever [32] illustrates these trends for the analysis of glycerine in soap. Samples are prepared by blending about 10 g of soap with 200 ml of N.N-dimethyl formamide. After filtration to remove insoluble soap, a portion of the solution is reacted with BSTFA (bis-trimethylsilyltrifuroacetamide) to produce the silylated glycerine derivative. The column used is a 12 m × 0.2 mm i.d. fused silica capillary coated with methyl silicone fluid. Glycerol was analyzed isothermally at 100°C. Quantitation was dne by comparing peak areas of the sample with peak areas of external standards.
Gas Chromatographic Analysis
Adorjan Aszalos in Modern Analysis of Antibiotics, 2020
Brown [13] reported on the analyses of formulations of this fungicide. The flask-heater-injection port and column (1% QF-1 on Gas Chrom Q 80/100) were both at 200°C and the FID at 225°C. The internal standard was cholesteryl acetate and silylating agent was a combination of TMCS and BSTFA. Initially, two peaks of derivatized cycloheximide were observed, the mono- and disubstituted derivatives. By adding isopropanol, quantitative yields of only the monosubstitution derivative were obtained. Mass spectrometry was used to identify the observed peaks.
Superior anti-neoplastic activities of triacontanol-PEG conjugate: synthesis, characterization and biological evaluations
Published in Drug Delivery, 2018
Yimeng Zhou, Ning Li, Zhixia Qiu, Xiaoyu Lu, Min Fang, Xijing Chen, Lili Ren, Guangji Wang, Pingkai Ouyang
TA (purity >95%) was kindly offered by kindly offered by Clinical Pharmacokinetics Research Laboratory, China Pharmaceutical University (NanjingNa, China). Monomethoxy Poly (ethylene glycol) amine 2 K (mPEG2K-NH2) used to graft with succinic acid (one end formed amide and the other exposed carboxyl) was purchased from Ponsure Company (Shanghai, China) with poly dispersity around 1.05, the purity (>95%) was testified by 1H-NMR. 1-Ethyl-3-(3-dimethylaminopropyl) carbodiimide (EDCI), 4-dimethylaminopyridine (DMAP), N, N-Diisopropylethylamine (DIPEA) were purchased from Sigma-Aldrich (St. Louis, MO, USA). Succinic acid (SA) was purchased from J&K Chemical Ltd. (Shanghai, China). mPEG2K-SA-TA (NMR purity, 95.0%) was prepared and purified by ToYongBio Ltd. (Shanghai, China). The HPLC grade solvents used (methanol, acetonitrile and heptane) were purchased from Tedia (Fairfield, OH, USA). The derivatization reagent, N, O-Bis (trimethylsilyl) trifluoroacetamide (BSTFA) was purchased from Aladdin (Shanghai, China). Distilled water was prepared using a Milli-Q water purification system. Ammonium acetate was supplied by Sinopharm Chemical Reagent Co., Ltd (Shanghai, China). All other chemicals and agents were of analytical grade from Nanjing Chemical Reagent No. 1 Factory (Nanjing, China).
Enhanced full-thickness wound healing via Sophora gibbosa extract delivery based on a chitosan/gelatin dressing incorporating microemulsion
Published in Drug Development and Industrial Pharmacy, 2021
Khaled Shalaby, Ehab M. Mostafa, Arafa Musa, Abd El Ghany A. Moustafa, Mohamed F. Ibrahim, Nabil K. Alruwaili, Ameeduzzafar Zafar, Mohammed Elmowafy
Pluronic F127 was purchased from Sigma Aldrich (Germany). Sorbitane monooleate (Span 80), polysorbate 80 (Tween 80), polyethylene glycol 400 (PEG 400) and polyethylene glycol 1500 (PEG 1500) were purchased from Lobal Chemie (India). Transcutol HP was kindly gifted by Gattefose (France). Chitosan (molecular weight: 100,000-300,000; degree of deacetylation: 85%) was purchased from ACROS organics (USA). Gelatin (molecular weight: 20 kDa) and glycerol were purchased from MERK (Germany). The aerial parts of Sophora gibbosa were collected in April 2018 from the desert of Aljouf region, in the north of the Kingdom of Saudi Arabia (KSA). It was identified by Mr. Hamdan Ogereef Al-Hassan, M.Sc. (Camel and Range Research Center), Aljouf, KSA. A voucher specimen was kept and deposited at the herbarium of the Pharmacognosy Department, College of Pharmacy, Jouf University. Trimethylchlorosilane (TMCS) and N,O-bis-trimethylsilyltrifluroacetamide (BSTFA) were purchased from Sigma-Aldrich (St. Louis, MO, USA). All the other chemicals, reagents and solvents used were of analytical reagent grade.
Metabolism of cyclic phenones in rainbow trout in vitro assays
Published in Xenobiotica, 2020
Jose Serrano, Mark A. Tapper, Richard C. Kolanczyk, Barbara R. Sheedy, Tylor Lahren, Dean E. Hammermeister, Jeffrey S. Denny, Michael W. Hornung, Alena Kubátová, Patricia A. Kosian, Jessica Voelker, Patricia K. Schmieder
Hexane extracts of TEDG buffer, binding cytosols, and slice exposure media were analyzed by GC-MS for parent chemicals and metabolites with adequate volatility, sensitivity and thermal stability. Extracts were analyzed on an Agilent 6890 N gas chromatograph connected to either an Agilent 5975 Inert XL or Agilent 5973 mass selective detector (Agilent Technologies, Santa Clara, CA, USA) using the conditions reported by Tapper et al. (2018b) and reproduced in Supplemental Table 1. Electron and chemical ionization approaches were used for qualitative analyses. Selected- or total-ion methods were used for quantitative studies (see Data analysis section). Due to the limited quantity of metabolites formed, chemical derivatization with BSTFA or MSTFA was performed in some 24 h slice-incubated CPK samples prior to GC-MS as described by Segura et al. (1998) to confirm the presence, relative yield and thermal stability of hydroxylated CPK metabolites in reaction mixtures (Serrano et al., 2019).
Related Knowledge Centers
- Gas Chromatography
- Organosilicon Chemistry
- Hydroxy Group
- Silyl Ether
- Bis(Trimethylsilyl)Acetamide