Pub Date : 2018-01-01DOI: 10.1080/23312009.2018.1443689
K. L. Kaygorodov, V. Tarabanko, N. Tarabanko
Abstract Thermodynamics of sodium butoxide-catalyzed polymerization of α-angelicalactone (a five-member unsaturated lactone) is studied by calorimetric methods. A polymer with Mw = 2,500 g/mol and the ratio of C–O to C–C inter-monomeric bonds 87–13% is obtained; this polymerization is characterized by the values of = −33.41 kJ/mol, = −42.69 J/(mol∙K) and = −20.68 kJ/mol. This and similar polymers and copolymers are biodegradable and can be produced from commercially available green bio-platform feedstock: renewable carbohydrates and levulinic acid.
{"title":"Thermodynamics of α-angelicalactone polymerization","authors":"K. L. Kaygorodov, V. Tarabanko, N. Tarabanko","doi":"10.1080/23312009.2018.1443689","DOIUrl":"https://doi.org/10.1080/23312009.2018.1443689","url":null,"abstract":"Abstract Thermodynamics of sodium butoxide-catalyzed polymerization of α-angelicalactone (a five-member unsaturated lactone) is studied by calorimetric methods. A polymer with Mw = 2,500 g/mol and the ratio of C–O to C–C inter-monomeric bonds 87–13% is obtained; this polymerization is characterized by the values of = −33.41 kJ/mol, = −42.69 J/(mol∙K) and = −20.68 kJ/mol. This and similar polymers and copolymers are biodegradable and can be produced from commercially available green bio-platform feedstock: renewable carbohydrates and levulinic acid.","PeriodicalId":10640,"journal":{"name":"Cogent Chemistry","volume":" ","pages":""},"PeriodicalIF":0.0,"publicationDate":"2018-01-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"https://sci-hub-pdf.com/10.1080/23312009.2018.1443689","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"43675894","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
Pub Date : 2018-01-01DOI: 10.1080/23312009.2018.1476077
Atakilt Abebe, M. Atlabachew, Misganaw Liyew, Elsabet Ferede
Abstract Molecular 1,10-phenanthroline has superb intercalation ability with DNA base pairs. However, it could not be used for medicinal applications. This is due to its toxicity caused by inhibiting metalloenzymes via its chelating nitrogen atoms. Nonetheless, the toxicity has been avoided for its attractive features coordinating with transition metals. However, this required lengthy synthetic work and rendering the final application is more laborious, expensive and less environmentally friendly. Moreover, this usually results in rigid three-dimensional complexes that prevents the complete intercalation of the coordinated 1,10-phenanthroline with DNA base pairs which diminishes its activity. In this work, an alternative strategy in diminishing the toxicity but retaining the flat geometry of 1,10-phenanthroline following simpler synthetic procedure without the involvement of transition metals is described. This was achieved synthesizing five N-alkyl-1,10-phenanthrolinium bromide salts. The salts were characterized by spectrometry (1H NMR, ESI MS, Uv-vis), CHNBr elemental analysis and conductivity measurements. All demonstrated amphiphilic property, which make their applications convenient. Their in vitro biological activities were tested on two Gram-positive (Staphylococcus aureus (S. aureus) and Streptococcus pyogens (S. pyogenes) and two Gram-negative (Eschercia coli (E. coli) and Klebsiella pneumoniae (K. pneumoniae) bacteria and compared with 1,10-phenanthroline. They are found active against all the tested bacteria. The minimum inhibitory concentrations of the salts are nearly the same as 1,10-phenanthroline. The increase in the alkyl chain length increased the antibacterial activities of the slats in all the tested bacteria. All the salts demonstrated high molar conductivities.
{"title":"Synthesis of organic salts from 1,10-phenanthroline for biological applications","authors":"Atakilt Abebe, M. Atlabachew, Misganaw Liyew, Elsabet Ferede","doi":"10.1080/23312009.2018.1476077","DOIUrl":"https://doi.org/10.1080/23312009.2018.1476077","url":null,"abstract":"Abstract Molecular 1,10-phenanthroline has superb intercalation ability with DNA base pairs. However, it could not be used for medicinal applications. This is due to its toxicity caused by inhibiting metalloenzymes via its chelating nitrogen atoms. Nonetheless, the toxicity has been avoided for its attractive features coordinating with transition metals. However, this required lengthy synthetic work and rendering the final application is more laborious, expensive and less environmentally friendly. Moreover, this usually results in rigid three-dimensional complexes that prevents the complete intercalation of the coordinated 1,10-phenanthroline with DNA base pairs which diminishes its activity. In this work, an alternative strategy in diminishing the toxicity but retaining the flat geometry of 1,10-phenanthroline following simpler synthetic procedure without the involvement of transition metals is described. This was achieved synthesizing five N-alkyl-1,10-phenanthrolinium bromide salts. The salts were characterized by spectrometry (1H NMR, ESI MS, Uv-vis), CHNBr elemental analysis and conductivity measurements. All demonstrated amphiphilic property, which make their applications convenient. Their in vitro biological activities were tested on two Gram-positive (Staphylococcus aureus (S. aureus) and Streptococcus pyogens (S. pyogenes) and two Gram-negative (Eschercia coli (E. coli) and Klebsiella pneumoniae (K. pneumoniae) bacteria and compared with 1,10-phenanthroline. They are found active against all the tested bacteria. The minimum inhibitory concentrations of the salts are nearly the same as 1,10-phenanthroline. The increase in the alkyl chain length increased the antibacterial activities of the slats in all the tested bacteria. All the salts demonstrated high molar conductivities.","PeriodicalId":10640,"journal":{"name":"Cogent Chemistry","volume":" ","pages":""},"PeriodicalIF":0.0,"publicationDate":"2018-01-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"https://sci-hub-pdf.com/10.1080/23312009.2018.1476077","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"45011842","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
Pub Date : 2018-01-01DOI: 10.1080/23312009.2018.1447262
C. Castro-Guerrero, A. Morales‐Cepeda, L.K. Hernández-Vega, M. R. Díaz-Guillén
Abstract Gold nanoparticles were synthesized at room temperature and atmospheric pressure using fructose, a common and non-toxic monosaccharide. The nanoparticles were mostly spherical, with a homogenous shape and a small size distribution. Fructose was a reducing and stabilizing agent, and the stability of the nanoparticles depended on its concentration.
{"title":"Fructose-mediated gold nanoparticles synthesis","authors":"C. Castro-Guerrero, A. Morales‐Cepeda, L.K. Hernández-Vega, M. R. Díaz-Guillén","doi":"10.1080/23312009.2018.1447262","DOIUrl":"https://doi.org/10.1080/23312009.2018.1447262","url":null,"abstract":"Abstract Gold nanoparticles were synthesized at room temperature and atmospheric pressure using fructose, a common and non-toxic monosaccharide. The nanoparticles were mostly spherical, with a homogenous shape and a small size distribution. Fructose was a reducing and stabilizing agent, and the stability of the nanoparticles depended on its concentration.","PeriodicalId":10640,"journal":{"name":"Cogent Chemistry","volume":" ","pages":""},"PeriodicalIF":0.0,"publicationDate":"2018-01-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"https://sci-hub-pdf.com/10.1080/23312009.2018.1447262","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"44239904","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
Pub Date : 2018-01-01DOI: 10.1080/23312009.2018.1559435
K. Alamry, M. Hussein, Youssef O. Al-Ghamdi, Tamer S. Saleh, Abdullah M. Asiri, Alawiah M. Alhebshi
Abstract A series of chitosan-based β-ketosulfone derivatives (CsB-β-KS) were synthesized, characterized, and evaluated as anti-cancer agents against three types of cancer cell lines, including the colon carcinoma (HCT), liver hepatocellular carcinoma (HEPG2), and breast carcinoma (MCF-7) cell lines. Before product formation, the β-ketosulfone derivatives, 1-(4-halophenyl)-2-(phenylsulfonyl)ethanone, were synthesized by the reaction of phenacyl halide with sodium benzene sulfinate. The (CsB-β-KS)a-e derivatives were synthesized by chemical modification of chitosan (Cs) with freshly prepared p-halo-β-ketosulfone derivatives in a mildly acidic aqueous solution. Various loading percentages, 5%, 10%, 15%, and 20%, of the p-halo-β-ketosulfone derivative (by weight) with respect to the Cs weight were evaluated. The chemical structures were confirmed by variable elemental and spectral analyses, including FT-IR, 1H-NMR, 13C-NMR, and mass spectroscopes. The (CsB-β-KS)a-e derivatives were also characterized by various techniques, such as FT-IR, 1H-NMR, XRD, FE-SEM, and thermal analyses. FT-IR spectroscopy and XRD confirmed the formation of these products. Moreover, the XRD results proved the strong interactions between the organic substituent and the Cs host molecule. All (CsB-β-KS)a-e derivatives showed similar thermal stabilities in three degradation steps. Among these derivatives, (CsB-β-KS)a3 showed the highest thermal stability. The synthesized compounds showed significant biological screening against Gram-positive and Gram-negative bacteria and fungi. Among the tested products, (CsB-β-KS)a3 displayed high efficiencies toward the three types of cancer cell lines under investigation with low concentrations. The ranking of the anti-cancer activity was (CsB-β-KS)a3 > (CsB-β-KS)d3 > (CsB-β-KS)d2.
{"title":"Potential anti-cancer performance of chitosan-based β-ketosulfone derivatives","authors":"K. Alamry, M. Hussein, Youssef O. Al-Ghamdi, Tamer S. Saleh, Abdullah M. Asiri, Alawiah M. Alhebshi","doi":"10.1080/23312009.2018.1559435","DOIUrl":"https://doi.org/10.1080/23312009.2018.1559435","url":null,"abstract":"Abstract A series of chitosan-based β-ketosulfone derivatives (CsB-β-KS) were synthesized, characterized, and evaluated as anti-cancer agents against three types of cancer cell lines, including the colon carcinoma (HCT), liver hepatocellular carcinoma (HEPG2), and breast carcinoma (MCF-7) cell lines. Before product formation, the β-ketosulfone derivatives, 1-(4-halophenyl)-2-(phenylsulfonyl)ethanone, were synthesized by the reaction of phenacyl halide with sodium benzene sulfinate. The (CsB-β-KS)a-e derivatives were synthesized by chemical modification of chitosan (Cs) with freshly prepared p-halo-β-ketosulfone derivatives in a mildly acidic aqueous solution. Various loading percentages, 5%, 10%, 15%, and 20%, of the p-halo-β-ketosulfone derivative (by weight) with respect to the Cs weight were evaluated. The chemical structures were confirmed by variable elemental and spectral analyses, including FT-IR, 1H-NMR, 13C-NMR, and mass spectroscopes. The (CsB-β-KS)a-e derivatives were also characterized by various techniques, such as FT-IR, 1H-NMR, XRD, FE-SEM, and thermal analyses. FT-IR spectroscopy and XRD confirmed the formation of these products. Moreover, the XRD results proved the strong interactions between the organic substituent and the Cs host molecule. All (CsB-β-KS)a-e derivatives showed similar thermal stabilities in three degradation steps. Among these derivatives, (CsB-β-KS)a3 showed the highest thermal stability. The synthesized compounds showed significant biological screening against Gram-positive and Gram-negative bacteria and fungi. Among the tested products, (CsB-β-KS)a3 displayed high efficiencies toward the three types of cancer cell lines under investigation with low concentrations. The ranking of the anti-cancer activity was (CsB-β-KS)a3 > (CsB-β-KS)d3 > (CsB-β-KS)d2.","PeriodicalId":10640,"journal":{"name":"Cogent Chemistry","volume":" ","pages":""},"PeriodicalIF":0.0,"publicationDate":"2018-01-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"https://sci-hub-pdf.com/10.1080/23312009.2018.1559435","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"43604202","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
Pub Date : 2018-01-01DOI: 10.1080/23312009.2018.1450944
M. Foreman
Abstract A review and discussion of some of the literature on the subject of serious nuclear reactor accidents. This review addresses some biological issues such as the influence of dose rate on the ability of radiation to cause harm, the chemistry of a selection of serious accidents and the behaviour of a series of important fission products and the actinides. This review is intended for scientists with a professional interest in nuclear reactors, chemists in general and I expect that it will be of use to historians with an interest in the nuclear industry and its relationship with wider society.
{"title":"Reactor accident chemistry an update","authors":"M. Foreman","doi":"10.1080/23312009.2018.1450944","DOIUrl":"https://doi.org/10.1080/23312009.2018.1450944","url":null,"abstract":"Abstract A review and discussion of some of the literature on the subject of serious nuclear reactor accidents. This review addresses some biological issues such as the influence of dose rate on the ability of radiation to cause harm, the chemistry of a selection of serious accidents and the behaviour of a series of important fission products and the actinides. This review is intended for scientists with a professional interest in nuclear reactors, chemists in general and I expect that it will be of use to historians with an interest in the nuclear industry and its relationship with wider society.","PeriodicalId":10640,"journal":{"name":"Cogent Chemistry","volume":" ","pages":""},"PeriodicalIF":0.0,"publicationDate":"2018-01-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"https://sci-hub-pdf.com/10.1080/23312009.2018.1450944","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"41829460","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
Pub Date : 2018-01-01DOI: 10.1080/23312009.2018.1562858
I. Asiamah, E. Krol
Abstract Reactive metabolites (RMs) have been implicated in many drug-induced toxicities including hepatotoxicity. Nordihydroguaiaretic acid (NDGA) has known pharmacological properties but its use is also associated with toxicities possibly mediated by RMs. In our effort to design and prepare NDGA analogues with better safety profile through rational structural modification, we first evaluated metabolic activation potential of model compounds mimicking catechol- and phenol-type NDGA analogues. We incubated test compounds in rat liver microsomes (RLM) in the presence of glutathione as nucleophilic trapping agent. We also investigated their potential to form para-quinone methides using silver oxide. Glutathione conjugates were detected by electrospray ionization-mass spectrometry (ESI-MS) scanning for neutral loss (NL) 129 or 307 in positive ion mode or precursor ion (PI) scanning for 272 in negative ion mode and further characterized by liquid chromatography–tandem mass spectrometry (LC–MS/MS) or in a single LC-MS run using multiple reactions monitoring (MRM) as a survey scan to trigger acquisition of enhanced product ion (EPI) data. Our findings led us to subsequently design and synthesize a series of NDGA analogues for evaluating their metabolic activation potential with a goal of eliminating RMs liability. Among others, we found that catechol-type analogues were converted to ortho-quinones by cytochrome P450s. We saw no evidence of RMs by cytochrome P450s for phenol-type analogues. This suggest that phenol-type NDGA analogues might not be associated with reactive metabolites-mediated toxicities. Although a more extensive pharmacological evaluation is underway, our preliminary results revealed that pharmacological properties were not compromised.
{"title":"Quadrupole linear ion-trap mass spectrometry studies on glutathione conjugates of nordihydroguaiaretic acid (NDGA) analogues reveals phenol-type analogues are without reactive metabolite-mediated toxic liability","authors":"I. Asiamah, E. Krol","doi":"10.1080/23312009.2018.1562858","DOIUrl":"https://doi.org/10.1080/23312009.2018.1562858","url":null,"abstract":"Abstract Reactive metabolites (RMs) have been implicated in many drug-induced toxicities including hepatotoxicity. Nordihydroguaiaretic acid (NDGA) has known pharmacological properties but its use is also associated with toxicities possibly mediated by RMs. In our effort to design and prepare NDGA analogues with better safety profile through rational structural modification, we first evaluated metabolic activation potential of model compounds mimicking catechol- and phenol-type NDGA analogues. We incubated test compounds in rat liver microsomes (RLM) in the presence of glutathione as nucleophilic trapping agent. We also investigated their potential to form para-quinone methides using silver oxide. Glutathione conjugates were detected by electrospray ionization-mass spectrometry (ESI-MS) scanning for neutral loss (NL) 129 or 307 in positive ion mode or precursor ion (PI) scanning for 272 in negative ion mode and further characterized by liquid chromatography–tandem mass spectrometry (LC–MS/MS) or in a single LC-MS run using multiple reactions monitoring (MRM) as a survey scan to trigger acquisition of enhanced product ion (EPI) data. Our findings led us to subsequently design and synthesize a series of NDGA analogues for evaluating their metabolic activation potential with a goal of eliminating RMs liability. Among others, we found that catechol-type analogues were converted to ortho-quinones by cytochrome P450s. We saw no evidence of RMs by cytochrome P450s for phenol-type analogues. This suggest that phenol-type NDGA analogues might not be associated with reactive metabolites-mediated toxicities. Although a more extensive pharmacological evaluation is underway, our preliminary results revealed that pharmacological properties were not compromised.","PeriodicalId":10640,"journal":{"name":"Cogent Chemistry","volume":" ","pages":""},"PeriodicalIF":0.0,"publicationDate":"2018-01-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"https://sci-hub-pdf.com/10.1080/23312009.2018.1562858","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"44574017","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
Pub Date : 2018-01-01DOI: 10.1080/23312009.2018.1487258
Zhichao Chen, R. Luck
Abstract Reactions between Al containing materials and counterfeit refrigerant chloromethane (R-40) were investigated under various conditions. The addition of Mg effected a reaction indicating that trimethylaluminum may have been produced in the reaction. A different study involving Al-foil, AlCl3 and chloromethane resulted in cracks detected on the Al-foil which reduced in weight by 19% and methane was detected. Studies conducted either at room temperature or at 80°C with two other genuine refrigerants, R-142b (1-chloro-1,1-difluoroethane) and R-133a (2-chloro-1,1,1-trifluoroethane) did not form organoaluminum compounds. Several commercially available refrigerant oils were subjected to Me3Al. Only polyester oil resulted in a decrease in the quantity of methane released upon final deactivation with alcohol. Various chemicals were added to Me3Al in order to find which ones would react and not produce methane. Phthalaldehyde was determined to be the most efficient reagent by deactivating approximately 50% of the methyl groups on Me3Al.
{"title":"Production of trimethylaluminum (Me3Al) with counterfeit refrigerant chloromethane (R-40), reactivity of Me3Al with refrigerant oils and methods to deactivate Me3Al","authors":"Zhichao Chen, R. Luck","doi":"10.1080/23312009.2018.1487258","DOIUrl":"https://doi.org/10.1080/23312009.2018.1487258","url":null,"abstract":"Abstract Reactions between Al containing materials and counterfeit refrigerant chloromethane (R-40) were investigated under various conditions. The addition of Mg effected a reaction indicating that trimethylaluminum may have been produced in the reaction. A different study involving Al-foil, AlCl3 and chloromethane resulted in cracks detected on the Al-foil which reduced in weight by 19% and methane was detected. Studies conducted either at room temperature or at 80°C with two other genuine refrigerants, R-142b (1-chloro-1,1-difluoroethane) and R-133a (2-chloro-1,1,1-trifluoroethane) did not form organoaluminum compounds. Several commercially available refrigerant oils were subjected to Me3Al. Only polyester oil resulted in a decrease in the quantity of methane released upon final deactivation with alcohol. Various chemicals were added to Me3Al in order to find which ones would react and not produce methane. Phthalaldehyde was determined to be the most efficient reagent by deactivating approximately 50% of the methyl groups on Me3Al.","PeriodicalId":10640,"journal":{"name":"Cogent Chemistry","volume":" ","pages":""},"PeriodicalIF":0.0,"publicationDate":"2018-01-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"https://sci-hub-pdf.com/10.1080/23312009.2018.1487258","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"44741654","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
Pub Date : 2018-01-01DOI: 10.1080/23312009.2018.1480455
Chien-Hsun Chen, Hua‐tao Feng, R. Guo, Pingjing Li, A. K. Laserna, Ya Ji, Bao Hui Ng, Sam F. Y. Li, S. Khan, A. Paulus, Shiaw-Min Chen, A. Karger, M. Wenz, Daniel Lopez Ferrer, A. Huhmer, A. Krupke
Abstract Determining and linking the structural heterogeneity of recombinant antibodies to function is critical in the biopharmaceutical industry. We introduce a new microfluidic capillary electrophoresis—mass spectrometry (μCE-MS) approach to characterize intact monoclonal antibody (mAb) and simultaneously quantifying distinct variants. Our MS analysis of intact NIST mAb (RM8671) shows 18 variants identified amongst proteolytic and glycolytic modifications with a range of relative abundances between 0.1% and 100%. In order to verify our quantitative MS results, we used an established system based on capillary electrophoresis—with laser induced fluorescence (CE-LIF) for profiling the N-glycans. All major glycans were identified and further substantiated by exoglycosidase digestion. Interestingly, the µCE-MS analysis of intact NIST mAb consistently yielded higher amounts of G2FG2F-Hex glycoform (~3.4%), whereas the CE-LIF analysis indicates that only 1.4% of G2F-Gal is present. Therefore, the additional hexose adduct observed in µCE-MS may have been the glycation product of the mAb. Further analysis of deglycosylated mAb with µCE-MS made it possible to reveal the glycation with 10.5% of one hexose product and 4.9% of two hexose product in the intact deglycosylated antibody. An integrated solution using two orthogonal and complementary techniques for characterizing antibody glycosylation is provided here.
{"title":"Intact NIST monoclonal antibody characterization—Proteoforms, glycoforms—Using CE-MS and CE-LIF","authors":"Chien-Hsun Chen, Hua‐tao Feng, R. Guo, Pingjing Li, A. K. Laserna, Ya Ji, Bao Hui Ng, Sam F. Y. Li, S. Khan, A. Paulus, Shiaw-Min Chen, A. Karger, M. Wenz, Daniel Lopez Ferrer, A. Huhmer, A. Krupke","doi":"10.1080/23312009.2018.1480455","DOIUrl":"https://doi.org/10.1080/23312009.2018.1480455","url":null,"abstract":"Abstract Determining and linking the structural heterogeneity of recombinant antibodies to function is critical in the biopharmaceutical industry. We introduce a new microfluidic capillary electrophoresis—mass spectrometry (μCE-MS) approach to characterize intact monoclonal antibody (mAb) and simultaneously quantifying distinct variants. Our MS analysis of intact NIST mAb (RM8671) shows 18 variants identified amongst proteolytic and glycolytic modifications with a range of relative abundances between 0.1% and 100%. In order to verify our quantitative MS results, we used an established system based on capillary electrophoresis—with laser induced fluorescence (CE-LIF) for profiling the N-glycans. All major glycans were identified and further substantiated by exoglycosidase digestion. Interestingly, the µCE-MS analysis of intact NIST mAb consistently yielded higher amounts of G2FG2F-Hex glycoform (~3.4%), whereas the CE-LIF analysis indicates that only 1.4% of G2F-Gal is present. Therefore, the additional hexose adduct observed in µCE-MS may have been the glycation product of the mAb. Further analysis of deglycosylated mAb with µCE-MS made it possible to reveal the glycation with 10.5% of one hexose product and 4.9% of two hexose product in the intact deglycosylated antibody. An integrated solution using two orthogonal and complementary techniques for characterizing antibody glycosylation is provided here.","PeriodicalId":10640,"journal":{"name":"Cogent Chemistry","volume":" ","pages":""},"PeriodicalIF":0.0,"publicationDate":"2018-01-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"https://sci-hub-pdf.com/10.1080/23312009.2018.1480455","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"48262828","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
Pub Date : 2018-01-01DOI: 10.1080/23312009.2018.1455346
Abdullah M. A. Shumaila
Abstract K2CO3/Al2O3 (KCA) is an efficient heterogeneous catalyst for the Michael addition reaction of 1,3-dicarbonyl compounds to nitro olefin under thermal solvent-free conditions. The results showed that the catalyst has high activity and the desired products were obtained in high yields. Furthermore, the products could be separated simply from the catalyst, and the catalyst could be recycled and reused with only slight reduction in its catalytic activity.
{"title":"K2CO3/Al2O3: An efficient and recyclable catalyst under solvent free conditions for the reaction of electron-deficient nitro-olefins with 1,3-dicarbonyl compounds","authors":"Abdullah M. A. Shumaila","doi":"10.1080/23312009.2018.1455346","DOIUrl":"https://doi.org/10.1080/23312009.2018.1455346","url":null,"abstract":"Abstract K2CO3/Al2O3 (KCA) is an efficient heterogeneous catalyst for the Michael addition reaction of 1,3-dicarbonyl compounds to nitro olefin under thermal solvent-free conditions. The results showed that the catalyst has high activity and the desired products were obtained in high yields. Furthermore, the products could be separated simply from the catalyst, and the catalyst could be recycled and reused with only slight reduction in its catalytic activity.","PeriodicalId":10640,"journal":{"name":"Cogent Chemistry","volume":" ","pages":""},"PeriodicalIF":0.0,"publicationDate":"2018-01-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"https://sci-hub-pdf.com/10.1080/23312009.2018.1455346","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"48496280","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
Pub Date : 2018-01-01DOI: 10.1080/23312009.2018.1536311
Samar Al Jitan, Saeed AlKhoori, Michael A. Ochsenkühn, Shady A. Amin, Lina F. Yousef
Abstract Microwave-assisted extraction using various concentrations of ethanol in water (25%, 50%, 75% v/v) was carried out using biomass from halophytes; Arthrocnemum macrostachyum and Tetraena qatarensis. Total phenolic content (TPC; expressed as mg Gallic acid equivalent; GAE) and antioxidant activity using half-maximal inhibitory concentration of DPPH-free radical (IC50; expressed as µg/mL) was highest in extracts from 75% ethanol in both plant species; TPC = 45.6 ± 1.0 and 54.4 ± 0.8 mg GAE/g extract; IC50 = 62.7 ± 0.4 and 67.9 ± 4.8 µg/mL for A. macrostachyum and T. qatarensis, respectively. UV-VIS spectral analysis and metabolome profile analysis obtained using UHPLC-Q-ToF-MS suggest the 50% and 75% ethanol extracts are similar in A. macrostachyum, whereas the 25% and 50% ethanol extracts are similar in T. qatarensis. Increasing the concentration of ethanol results in phytoextracts with greater chemical complexity.
{"title":"Ethanol/water extracts from halophyte species Arthrocnemum macrostachyum and Tetraena qatarensis","authors":"Samar Al Jitan, Saeed AlKhoori, Michael A. Ochsenkühn, Shady A. Amin, Lina F. Yousef","doi":"10.1080/23312009.2018.1536311","DOIUrl":"https://doi.org/10.1080/23312009.2018.1536311","url":null,"abstract":"Abstract Microwave-assisted extraction using various concentrations of ethanol in water (25%, 50%, 75% v/v) was carried out using biomass from halophytes; Arthrocnemum macrostachyum and Tetraena qatarensis. Total phenolic content (TPC; expressed as mg Gallic acid equivalent; GAE) and antioxidant activity using half-maximal inhibitory concentration of DPPH-free radical (IC50; expressed as µg/mL) was highest in extracts from 75% ethanol in both plant species; TPC = 45.6 ± 1.0 and 54.4 ± 0.8 mg GAE/g extract; IC50 = 62.7 ± 0.4 and 67.9 ± 4.8 µg/mL for A. macrostachyum and T. qatarensis, respectively. UV-VIS spectral analysis and metabolome profile analysis obtained using UHPLC-Q-ToF-MS suggest the 50% and 75% ethanol extracts are similar in A. macrostachyum, whereas the 25% and 50% ethanol extracts are similar in T. qatarensis. Increasing the concentration of ethanol results in phytoextracts with greater chemical complexity.","PeriodicalId":10640,"journal":{"name":"Cogent Chemistry","volume":" ","pages":""},"PeriodicalIF":0.0,"publicationDate":"2018-01-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"https://sci-hub-pdf.com/10.1080/23312009.2018.1536311","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"47978892","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
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