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Upstream processing for viral vaccines–General aspects
Published in Amine Kamen, Laura Cervera, Bioprocessing of Viral Vaccines, 2023
Lars Pelz, Sven Göbel, Karim Jaen, Udo Reichl, Yvonne Genzel
Finally, the vaccine type (live-attenuated, inactivated, vector) also has a significant impact on design and optimization of virus production processes. Many attenuated vaccine strains show a lower replication rate and, thus, often reduced virus yields. In contrast, manufacturing processes for inactivated vaccines that comprise infectious and non-infectious virus particles often display very high titers. For production of pathogenic viruses without an option to vaccinate employees (e.g., early production campaigns of SARS-CoV-2 in adherent Vero cells) safety considerations should have a high priority and may require handling of virus-containing materials at least in a BSL3 environment. For manufacturing of inactivated vaccines, inactivation (heat, formaldehyde, β-propiolactone) is necessary and needs to be carefully validated and confirmed by innocuity assays. For recombinant sub-unit vaccines, higher concentrations are needed due to the lower immune response they induce. Taking all these points together explains that process optimization for viral vaccine manufacturing can be very lengthy and complicated.
Physical Properties of Individual Groundwater Chemicals
Published in John H. Montgomery, Thomas Roy Crompton, Environmental Chemicals Desk Reference, 2017
John H. Montgomery, Thomas Roy Crompton
Synonyms: AI3-24257; AIDS-6024; Betaprone; BPL; BRN 0001360; Caswell No. 709; CCRIS 536; EINECS 200-340-1; EPA pesticide chemical code 010901; Hydracrylic acid β-lactone; 3-Hydroxypropionic acid lactone; β-Lactone; NSC 21626; Oxetan-2-one; 2-Oxetanone; Propanolide; Propiolactone; 1,3-Propiolactone; 3-Propiolactone; β-Propionolactone; 3-Propionolactone; β-Proprolactone; UN 2810.
Bacterial Polyesters and Their Models Obtained by Ring-Opening Polymerization of β-Lactones
Published in Stanislaw Penczek, H. R. Kricheldorf, A. Le Borgne, N. Spassky, T. Uryu, P. Klosinski, Models of Biopolymers by Ring-Opening Polymerization, 2018
Alain Le Borgne, Nicolas Spassky
The hydrolysis of β-trichloromethyl-β-propiolactone of a given configuration leads to the malic acid of opposite configuration.70 In this way both enantiomers of malic acid were prepared:
Determination of non-freezing water in different nonfouling materials by differential scanning calorimetry
Published in Journal of Biomaterials Science, Polymer Edition, 2022
Guanglong Ma, Fangqin Ji, Weifeng Lin, Shengfu Chen
[2-(Methacryloyloxy)ethyl]dimethyl-(3-sulfopropyl)ammonium hydroxide (SBMA, 97%) was purchased from Sigma-Aldrich (Shanghai, China). 2-(N, N′-dimethylamino)ethyl methacrylate (DMAEMA), 2,2′-azobis-(isobutyronitrile) (AIBN), PEG with an average molecular weight of 550, 5000, 20000 were purchased from Aladdin Reagent (Shanghai, China). Methanol was purchased from Sinopharm Chemical Reagent (Shanghai, China). β-Propiolactone was purchased from J&K (Beijing, China). CBMA was synthesized as previously reported [35,36]. Briefly, β-propiolactone (3.53 mL, 55 mmol) was diluted with 5 mL anhydrous acetone, and the mixture was added dropwise to a solution of DMAEM (8.43 mL, 50 mmol) in 45 mL anhydrous acetone. The reaction was kept under nitrogen protection with constant stirring at 15 °C for 6 h. Then the reaction mixture was filtrated, and a white solid was collected. The compound was washed with 50 mL anhydrous acetone, and stored at −20 °C before use. MPC was a kind gift from Prof. Jian Ji’s group (Department of Polymer Science and Engineering, Zhejiang University).
A review on solid base heterogeneous catalysts: preparation, characterization and applications
Published in Chemical Engineering Communications, 2022
Diksha K. Jambhulkar, Rajendra P. Ugwekar, Bharat A. Bhanvase, Divya P. Barai
Solid base catalysts have been used to polymerize several compounds such as formaldehyde, ethylene oxide, propylene oxide, lactam, β-propiolactone, etc. into their high polymers. Magnesium oxide, calcium oxide, strontium oxide, potassium carbonate, sodium carbonate, calcium carbonate, strontium carbonate, sodium hydroxide, calcium hydroxide, etc., have been widely used as solid base catalysts in polymerization processes. Solid base catalyst reacts with monomer to form a complex which is used in polymerization of lactam (Tanabe 1970). Wang et al. (2018) worked on carbon dioxide polymerization using potassium based alkali salts to produce polyureas and found that potassium phosphate results in higher catalytic activity due to its strong basicity as compared to other potassium based alkali solid base catalysts for polymerization of carbon dioxide. The base catalysts reacts to amino groups more strongly and helps in introduction of CO2 into the N-H bond of diamine molecules resulting in higher polymerization yield. Figure 23 depicts the mechanism involved in formation of Polyureas from diamines and CO2 using K3PO4 solid base catalyst. Here, diamine reacts with CO2 as soon as it comes in contact to form ammonium carbamate intermediate complex. K3PO4 catalyst allowed dehydration of the formed intermediate complex to produce distributed urea. Constant removal of water molecule resulted in formation of polyureas. The base PO43− present over the catalyst triggered the activation of carbamate intermediate complex. The reaction was carried out at temperatures ranging between 150 and 170 °C for about 8 h.
Validation of Quantitative Structure-Activity Relationship (QSAR) and Quantitative Structure-Property Relationship (QSPR) approaches as alternatives to skin sensitization risk assessment
Published in Journal of Toxicology and Environmental Health, Part A, 2021
Ji Yun Kim, Kyu-Bong Kim, Byung-Mu Lee
A previous correlative study between physicochemical properties and EC3 (%) values for 212 skin sensitizers and 38 non-sensitizers was performed by Kim et al. (2019a). In addition, the physicochemical properties and EC3 (%) values of new 93 skin sensitizers and 19 non-sensitizers reported were evaluated for a total of 305 sensitizers (previous 212 + 93 additional new chemicals) and 57 non-sensitizers (previous 38 + 19 additional new chemicals)(Chemicalbook 2019; NCBI (National Center for Biotechnology Information) 2019; NIST (National Institute of Standards and Technology) 2019; USEPA (United States Environmental Protection Agency) 2019). The following new 93 skin sensitizers were selected: 4-phenylenediamine; 2,5-dichlorobenzoquinone; chlorobenzoquinone; 2,6-dichloro-1,4-benzoquinone; 2ʹ,4ʹ- dihydroxychalcone; acetic anhydride; 2-methyl-p-benzoquinone; 2,5-dimethyl-p-benzoquinone; beta-propiolactone; chloroamine T; gold chloride; 3-phenyl propenal; 2-(4-amino-2-nitro-phenylamino)-ethanol; methyl pyruvate; basil oil; clove oil; damascone; trans-beta-damascone; t-alpha damascene; 5,5-dimethyl-3-methylenedihydro-2(3 H)-furanone; glyceryl thioglycollate; lemongrass oil; maleic acid; methylanisylidene acetone; oakmoss; octinol; tetramethylthiruam disulfide; thioglycerol; trifluralin EC; palmarosa oil; phenylpropionaldehyde; spearmint oil; squalene; 2,3-dihydro-2,2,6-trimethylbenzaldehyde; 4-hexen-3-one; methanesulfonyl chloride; carbamothioic chloride, dimethyl-; phenylmethanesulfonylchloride; dinitrobenzenesulfonic acid; p-isobutyl-α-methyl hydrocinnamaldehdye; 6-methyl-3,5-heptadien-2-one; 5-amino-2-methylphenol; 4-amino-m-cresol; 2,2ʹ-[(4-amino-3-nitrophenyl)imino]diethanol; (4-ethoxyphenyl)methanol; phenethyl bromide; 5-chlorosalicylanilide; 3-cyclohexene-1-carboxylic acid; 2,6-dimethoxy-3,5-pyridinediamine HCl; ethanol dihydrochloride; 3,4-dinitrophenol; ethylene glycol monohexadecyl ether; 3-methyl-1-phenyl-5-pyrazolone; alpha-phellandrene; beta-phellandrene; tropolone; 1-octen-3-yl acetate; vanillin; isocyclogeraniol; menthadiene-7-methylformate; 2-ethylbutyraldehyde; acetylcedrene; trimethylbenzenepropanol; benzyl alcohol; cinnamyl nitrile; 4,4-dibromobenzil; butyl acrylate; methyl acrylate; acetyl isovaleryl; benzocaine; atrazine; chlorpromazine; fatty acid; glutamate; linoleic acid; streptomycin; undecylenic acid; salicylic acid; pentachlorophenol; methylhexanedione; methylhydrocinnamal; oleic acid; oxyfluorfen EC; acetyl cedrene; phenethyl isovalerate; p-chlorophenethylic alcohol; colorex 13bis; 4,4ʹ-dibromobenzil; methylbis[2-(7-oxabicyclo[4.1.0]heptan-3-yl)ethyl]phenylsilane; bisphenol A glycidyl methacrylate; 3-(3,4-methylenedioxyphenyl)-2-methylpropanal; 6-(nonanoylamino)-2-(4-sulfophenyl)hexanoate; 2,2ʹ-azobisphenol; and tridecane.