scholarly journals Flurbiprofen: A Study of the Behavior of the Scalemate by Chromatography, Sublimation, and NMR

Symmetry ◽  
2021 ◽  
Vol 13 (4) ◽  
pp. 543
Author(s):  
Magdalena Kwiatkowska ◽  
Alicja Wzorek ◽  
Anna Kolbus ◽  
Mariusz Urbaniak ◽  
Jianlin Han ◽  
...  
Keyword(s):  
Relaxation Time ◽  
Preparative Thin Layer Chromatography ◽  
Transverse Relaxation Time ◽  
Size Exclusion ◽  
Test Case ◽  
Ionization Mass ◽  
Chiral Drugs ◽  
Good Test ◽  
Exclusion Chromatography ◽  
Medium Pressure Liquid Chromatography

2-(2-Fluoro-4-biphenyl) propionic acid (flurbiprofen), from the phenylalkanoic acid family of nonsteroidal anti-inflammatory drugs (NSAID’s), is currently on the pharmaceutical market as a racemate. This racemic compound was tested for its propensity to undergo the self-disproportionation of enantiomers (SDE) phenomenon by various forms of chromatography (SDEvC), such as routine gravity-driven column chromatography, medium-pressure liquid chromatography (MPLC), preparative thin-layer chromatography (PTLC), and size-exclusion chromatography (SEC), as well as by sublimation (SDEvS). Furthermore, examination by nuclear magnetic resonance (NMR) in various solvents found that flurbiprofen exhibited the phenomenon of self-induced diastereomeric anisochronism (SIDA). By measurement of the diffusion coefficient (D), the longitudinal relaxation time (T1), and the transverse relaxation time (T2) using NMR, as well as by electrospray ionization-mass spectrometry (ESI-MS) examinations, the preferred intermolecular association was found to be solvent dependent, e.g., heterochiral association was preferred in toluene, while homochiral association was preferred in more polar solvents. This study also attempted, unsuccessfully, to correlate the NMR measurements of flurbiprofen with chromatographic outcomes for the rationalization and prediction of chromatographic results based on NMR measurements. Because the intermolecular hydrogen bonding of the acid groups in flurbiprofen overwhelmingly predominates over other intermolecular interactions, flurbiprofen seemed to represent a good test case for this idea. The behavior of scalemic samples of flurbiprofen is important, as, although it is currently dispensed as a racemate, clinical applications of the R enantiomer have been investigated. SDEvC and SDEvS both have ramifications for the preparation, handling, and storage of enantioenriched flurbiprofen, and this concern applies to other chiral drugs as well.

scholarly journals Antibacterial Peptides Produced by Alcalase from Cowpea Seed Proteins

Antibiotics ◽  
2021 ◽  
Vol 10 (7) ◽  
pp. 870
Author(s):  
Ali Osman ◽  
Gamal Enan ◽  
Abdul-Raouf Al-Mohammadi ◽  
Seham Abdel-Shafi ◽  
Samar Abdel-Hameid ◽  
...  
Keyword(s):  
Size Exclusion Chromatography ◽  
Seed Proteins ◽  
Negative Ions ◽  
Size Exclusion ◽  
Ionization Mass ◽  
Bacterial Cells ◽  
Antibacterial Efficiency ◽  
Exclusion Chromatography ◽  
Molecular Masses ◽  
Cowpea Seed

Cowpea seed protein hydrolysates (CPH) were output from cowpea seeds applying alcalase® from Bacillus licheniformis. CPH with an elevated level of hydrolysis was fractionated by size exclusion chromatography (SEC). Both CPH and SEC-portions showed to contain antimicrobial peptides (AMPs) as they inhibited both Gram-positive bacteria, such as Listeria monocytogenes LMG10470 (L. monocytogenes), Listeria innocua. LMG11387 (L. innocua), Staphylococcus aureus ATCC25923 (S.aureus), and Streptococcus pyogenes ATCC19615 (St.pyogenes), and Gram-negative bacteria, such as Klebsiella pnemoniae ATCC43816 (K. pnemoniae), Pseudomonas aeroginosa ATCC26853 (P. aeroginosa), Escherichia coli ATCC25468) (E.coli) and Salmonella typhimurium ATCC14028 (S. typhimurium).The data exhibited that both CPH and size exclusion chromatography-fraction 1 (SEC-F1) showed high antibacterial efficiency versus almost all the assessed bacteria. The MIC of the AMPs within SEC-F1 and CPHs were (25 µg/mL) against P. aeruginosa, E.coli and St. pyogenes. However, higher MICsof approximately 100–150 µg/mL showed for both CPHs and SEC-F1 against both S. aureus and L. innocua; it was 50 µg/mL of CPH against S.aureus. The Electro-spray-ionization-mass-spectrometry (ESI-MS) of fraction (1) revealed 10 dipeptides with a molecular masses arranged from 184 Da to 364 Da and one Penta peptide with a molecular mass of approximately 659 Da inthe case of positive ions. While the negative ions showed 4 dipeptides with the molecular masses that arranged from 330 Da to 373 Da. Transmission electron microscope (TEM) demonstrated that the SEC-F1 induced changes in the bacterial cells affected. Thus, the results suggested that the hydrolysis of cowpea seed proteins by Alcalase is an uncomplicated appliance to intensify its antibacterial efficiency.

scholarly journals Optimization of Unnickedβ2-Glycoprotein I and High Avidity Anti-β2-Glycoprotein I Antibodies Isolation

2014 ◽  
Vol 2014 ◽  
pp. 1-8 ◽  
Author(s):  
Andrej Artenjak ◽  
Adrijana Leonardi ◽  
Igor Križaj ◽  
Aleš Ambrožič ◽  
Snezna Sodin-Semrl ◽  
...  
Keyword(s):  
Isolation Procedure ◽  
Size Exclusion ◽  
Ionization Mass ◽  
High Avidity ◽  
Isolation And Purification ◽  
Average Mass ◽  
Glycoprotein I ◽  
Unknown Protein ◽  
Exclusion Chromatography ◽  
Weight Protein

Patient biological material for isolation ofβ2-glycoprotein I (β2GPI) and high avidity IgG anti-β2-glycoprotein I antibodies (HAv anti-β2GPI) dictates its full utilization. The aim of our study was to evaluate/improve procedures for isolation of unnickedβ2GPI and HAv aβ2GPI to gain unmodified proteins in higher yields/purity. Isolation ofβ2GPI from plasma was a stepwise procedure combining nonspecific and specific methods. For isolation of polyclonal HAv aβ2GPI affinity chromatographies with immobilized protein G and humanβ2GPI were used. The unknown protein found during isolation was identified by liquid chromatography electrospray ionization mass spectrometry and the nonredundant National Center for Biotechnology Information database. The average mass of the isolated unnicked purifiedβ2GPI increased from 6.56 mg to 9.94 mg. In the optimized isolation procedure the high molecular weight protein (proteoglycan 4) was successfully separated fromβ2GPI in the 1st peaks with size exclusion chromatography. The average efficiency of the isolation procedure for polyclonal HAv anti-β2GPI from different matrixes was 13.8%, as determined by ourin-houseanti-β2GPI ELISA. We modified thein-houseisolation and purification procedures of unnickedβ2GPI and HAv anti-β2GPI, improving the purity of antigen and antibodies as well as increasing the number of tests routinely performed with thein-houseELISA by ~50%.

Molecular Weight and Tacticity of Oligoacrylates by Capillary Electrophoresis - Mass Spectrometry

2010 ◽  
Vol 63 (8) ◽  
pp. 1219 ◽  
Author(s):  
Marianne Gaborieau ◽  
Tim J. Causon ◽  
Yohann Guillaneuf ◽  
Emily F. Hilder ◽  
Patrice Castignolles
Keyword(s):  
Capillary Electrophoresis ◽  
Raft Polymerization ◽  
Degree Of Polymerization ◽  
Size Exclusion ◽  
Separation Mechanism ◽  
Ionization Mass ◽  
Polymeric Particles ◽  
Reversible Addition ◽  
Exclusion Chromatography

Oligo(acrylic acid) efficiently stabilizes polymeric particles, especially particles produced by reversible addition–fragmentation chain transfer (RAFT) (as hydrophilic block of an amphiphilic copolymer). Capillary electrophoresis (CE) has a far higher resolution power to separate these oligomers than the commonly used size exclusion chromatography. Coupling CE to electrospray ionization mass spectrometric detection unravels the separation mechanism. CE separates these oligomers, not only according to their degree of polymerization, but also according to their tacticity, in agreement with NMR analysis. Such analysis will provide insight into the role of these oligomers as stabilizers in emulsion polymerization, and into the mechanism of the RAFT polymerization with respect to degree of polymerization and tacticity.

Modification of acid hydrolysis lignin for value-added applications by micronization followed by hydrothermal alkaline treatment

Holzforschung ◽  
2015 ◽  
Vol 69 (6) ◽  
pp. 761-768 ◽  
Author(s):  
Stepan M. Krutov ◽  
Dmitry V. Evtuguin ◽  
Elena V. Ipatova ◽  
Sonia A.O. Santos ◽  
Yurii N. Sazanov
Keyword(s):  
Value Added ◽  
Alkaline Treatment ◽  
Raw Material ◽  
Size Exclusion ◽  
Resonance Spectroscopy ◽  
Ionization Mass ◽  
Hydrolysis Lignin ◽  
Molecular Weights ◽  
Exclusion Chromatography ◽  
L1 And L2

Abstract Technical hydrolysis lignin (THL) was micronized by grinding in a rotary-jet mill to obtain a fraction of approximately 5 mm. Both initial and milled THLs were liquefied by thermal alkaline treatment at 220°C for 2 h. Upgraded THLs that were nonmilled (L1) and milled (L2) were desalted by treatment with cation-exchanged resin and were dried. Micronization affected the course of hydrothermal alkaline treatment and the structure and composition of the obtained lignin. Thus, L2 contained much less concomitant polysaccharides and extractives than L1 and was more condensed. The molecular weights of L1 and L2 were 1100 and 1000 Da, respectively, as determined by size-exclusion chromatography. Structural characterization carried out by employing tandem electrospray ionization-mass spectrometry and 1D and 2D nuclear magnetic resonance spectroscopy revealed that small amounts of β-O-4 (∼6 mol.%), β-5, and β-β structures still remained in L1 and L2. Overall, upgraded lignins are oligomers (trimers-pentamers) with highly degraded propane chains and possess polyconjugated condensed aromatic structures. Upgraded THL seems to be a promising raw material for polymeric formulations.

Control of high molecular weight disinfection byproducts in drinking water by coagulation

2006 ◽  
Vol 6 (6) ◽  
pp. 137-146 ◽  
Author(s):  
X.R. Zhang ◽  
R.A. Minear
Keyword(s):  
Molecular Weight ◽  
High Molecular Weight ◽  
Disinfection Byproducts ◽  
Size Exclusion ◽  
Negative Ion ◽  
Ionization Mass ◽  
Esi Ms ◽  
Adverse Health Effects ◽  
Organic Halogen ◽  
Exclusion Chromatography

A major portion of the total organic halogen formed during chlorination is likely attributable to high molecular weight (MW) DBPs (above 500 Da), which may have potential adverse health effects. In this work, highly dosed chlorinated Suwannee River fulvic acid samples with and without coagulation pretreatment were separated and fractionated by using ultrafiltration (UF) and size exclusion chromatography (SEC) techniques. The SEC fractions corresponding to the high MW region were concentrated with nitrogen sparging and characterized by negative ion electrospray ionization/mass spectrometry (ESI-MS). The SEC–UV chromatograms and SEC–ESI-MS spectra show that coagulation greatly reduced the formation of high MW DBPs. It is of note that phosphate from the buffer could affect the ESI-MS characterization in 2–3 SEC fractions although most of the phosphate had been removed by UF.

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