scholarly journals Melt-Polymerization of Acrylamide Initiated by Nucleophiles: A Route Towards Highly Branched and Amorphous Polyamide 3

2020 ◽  
Author(s):  
David Edinger ◽  
Hansjörg Weber ◽  
Ema Žagar ◽  
David Pahovnik ◽  
Christian Slugovc
Keyword(s):  
Thermal Analyses ◽  
Ionic Species ◽  
Water Soluble ◽  
Size Exclusion ◽  
Melt Polymerization ◽  
Biomedical Systems ◽  
Exclusion Chromatography ◽  
Nmr Techniques ◽  
High Degree

The melt-polymerization of acrylamide initiated by nucleophiles allows for the preparation of polyamide 3 (PA 3) with a branching factor of about 1.5. The high share of branching units imparts a fully amorphous morphology featuring a low glass transition temperature of 67 °C and renders the polymer water soluble. The disclosed method provides an easy, resource-efficient and green access to a polymer interesting for applications in biological and biomedical systems. The obtained PA 3 was characterized by several NMR-techniques, MALDI-TOF mass spectrometry, size-exclusion chromatography, thermal analyses and powder-X-ray diffractometry. Preparation and characterization of a 15N-marked polymer complemented the elucidation of the polymers structure. Mechanistically, the polymerization can be considered as an aza-Michael polymerization of acrylamide involving zwitter-ionic species as the key intermediates being responsible for the high degree of branching. <br>

scholarly journals Melt-Polymerization of Acrylamide Initiated by Nucleophiles: A Route Towards Highly Branched and Amorphous Polyamide 3

2020 ◽  
Author(s):  
David Edinger ◽  
Hansjörg Weber ◽  
Ema Žagar ◽  
David Pahovnik ◽  
Christian Slugovc
Keyword(s):  
Thermal Analyses ◽  
Ionic Species ◽  
Water Soluble ◽  
Size Exclusion ◽  
Melt Polymerization ◽  
Biomedical Systems ◽  
Exclusion Chromatography ◽  
Nmr Techniques ◽  
High Degree

The melt-polymerization of acrylamide initiated by nucleophiles allows for the preparation of polyamide 3 (PA 3) with a branching factor of about 1.5. The high share of branching units imparts a fully amorphous morphology featuring a low glass transition temperature of 67 °C and renders the polymer water soluble. The disclosed method provides an easy, resource-efficient and green access to a polymer interesting for applications in biological and biomedical systems. The obtained PA 3 was characterized by several NMR-techniques, MALDI-TOF mass spectrometry, size-exclusion chromatography, thermal analyses and powder-X-ray diffractometry. Preparation and characterization of a 15N-marked polymer complemented the elucidation of the polymers structure. Mechanistically, the polymerization can be considered as an aza-Michael polymerization of acrylamide involving zwitter-ionic species as the key intermediates being responsible for the high degree of branching. <br>

Development and characterization of a formulation based covalent conjugation with polyacrylic acid and recombinant major surface antigen (SAG1) of Toxoplasma gondii

2017 ◽  
Vol 42 (6) ◽  
Author(s):  
Rabia Cakir Koc ◽  
Yasemin Budama Kilinc
Keyword(s):  
Vaccine Development ◽  
Surface Antigens ◽  
Water Soluble ◽  
Size Exclusion ◽  
Primary Amines ◽  
Exclusion Chromatography ◽  
Major Surface ◽  
First Time ◽  
Spontaneous Reaction

AbstractIntroduction:Toxoplasmosis is a major disease caused byMethods:PAA and SAG1 were covalently conjugated using a water-soluble carbodiimide crosslinker that activates carboxyl groups for spontaneous reaction with primary amines. To demonstrate conjugation of these molecules in size exclusion chromatography (SEC), fluorescence spectroscopy was used.Results:For the first time, one of the most important surface antigens ofDiscussion and conclusion:The obtained SAG1-PAA conjugate can be used for vaccine development against

The degradation of Indulin ATR by Streptomyces: chemical characterization of the water soluble acid precipitable products

1989 ◽  
Vol 67 (2) ◽  
pp. 350-355 ◽  
Author(s):  
P. F. Vidal ◽  
J. Bouchard ◽  
E. Chornet ◽  
R. P. Overend ◽  
H. Giroux ◽  
...  
Keyword(s):  
High Performance ◽  
Protein Complexes ◽  
Chemical Characterization ◽  
Water Soluble ◽  
Size Exclusion ◽  
Produce Water ◽  
Lignin Fraction ◽  
Exclusion Chromatography ◽  
Soluble Acid

Two strains of Streptomyces, S. badius and S. virdosporus, when incubated with kraft lignin (Indulin ATR) produce water soluble acid precipitable compounds. We show by a combination of elemental analysis, amino acid analysis, and FTIR that these are complexes of lignin fragments strongly associated with proteins. The latter, which can be separated by solvent extraction, are added by the microorganisms themselves. The lignin fraction, which represents approximately 60% of the complex weight, consists of lower molecular weight, lower methoxyl content Indulin fragments. KeyWords: lignin, Indulin, lignin–protein complexes, Fourier transform infrared spectrophotometry, high performance size exclusion chromatography, Streptomyces.

Structure of a shear-thickening polysaccharide extracted from the New Zealand black tree fern, Cyathea medullaris

2020 ◽  
Author(s):  
M Wee ◽  
M Mastrangelo ◽  
Susan Carnachan ◽  
Ian Sims ◽  
K Goh
Keyword(s):  
New Zealand ◽  
Uronic Acid ◽  
Average Molecular Weight ◽  
Shear Thickening ◽  
Water Soluble ◽  
Size Exclusion ◽  
Resonance Spectroscopy ◽  
Tree Fern ◽  
13C Nuclear Magnetic Resonance ◽  
Exclusion Chromatography

A shear-thickening water-soluble polysaccharide was purified from mucilage extracted from the fronds of the New Zealand black tree fern (Cyathea medullaris or 'mamaku' in Māori) and its structure characterised. Constituent sugar analysis by three complementary methods, combined with linkage analysis (of carboxyl reduced samples) and 1H and 13C nuclear magnetic resonance spectroscopy (NMR) revealed a glucuronomannan comprising a backbone of 4-linked methylesterified glucopyranosyl uronic acid and 2-linked mannopyranosyl residues, branched at O-3 of 45% and at both O-3 and O-4 of 53% of the mannopyranosyl residues with side chains likely comprising terminal xylopyranosyl, terminal galactopyranosyl, non-methylesterified terminal glucopyranosyl uronic acid and 3-linked glucopyranosyl uronic acid residues. The weight-average molecular weight of the purified polysaccharide was ~1.9×106Da as determined by size-exclusion chromatography coupled with multi-angle laser light scattering (SEC-MALLS). The distinctive rheological properties of this polysaccharide are discussed in relation to its structure. © 2014 Elsevier B.V.

scholarly journals Fibrillar pharmacology of functionalized nanocellulose

2021 ◽  
Vol 11 (1) ◽  
Author(s):  
Sam Wong ◽  
Simone Alidori ◽  
Barbara P. Mello ◽  
Bryan Aristega Almeida ◽  
David Ulmert ◽  
...  
Keyword(s):  
Aspect Ratio ◽  
Fluorescent Dyes ◽  
Pharmacokinetic Profile ◽  
Water Soluble ◽  
Size Exclusion ◽  
Hydroxyl Groups ◽  
Target Tissue ◽  
Exclusion Chromatography ◽  
Specific Accumulation

AbstractCellulose nanocrystals (CNC) are linear organic nanomaterials derived from an abundant naturally occurring biopolymer resource. Strategic modification of the primary and secondary hydroxyl groups on the CNC introduces amine and iodine group substitution, respectively. The amine groups (0.285 mmol of amine per gram of functionalized CNC (fCNC)) are further reacted with radiometal loaded-chelates or fluorescent dyes as tracers to evaluate the pharmacokinetic profile of the fCNC in vivo. In this way, these nanoscale macromolecules can be covalently functionalized and yield water-soluble and biocompatible fibrillar nanoplatforms for gene, drug and radionuclide delivery in vivo. Transmission electron microscopy of fCNC reveals a length of 162.4 ± 16.3 nm, diameter of 11.2 ± 1.52 nm and aspect ratio of 16.4 ± 1.94 per particle (mean ± SEM) and is confirmed using atomic force microscopy. Size exclusion chromatography of macromolecular fCNC describes a fibrillar molecular behavior as evidenced by retention times typical of late eluting small molecules and functionalized carbon nanotubes. In vivo, greater than 50% of intravenously injected radiolabeled fCNC is excreted in the urine within 1 h post administration and is consistent with the pharmacological profile observed for other rigid, high aspect ratio macromolecules. Tissue distribution of fCNC shows accumulation in kidneys, liver, and spleen (14.6 ± 6.0; 6.1 ± 2.6; and 7.7 ± 1.4% of the injected activity per gram of tissue, respectively) at 72 h post-administration. Confocal fluorescence microscopy reveals cell-specific accumulation in these target tissue sinks. In summary, our findings suggest that functionalized nanocellulose can be used as a potential drug delivery platform for the kidneys.

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