Synthesis and characterization of polyethylene glycol polyacrylamide copolymer (PEGA) resins containing carbohydrate ligands. Evaluation as supports for affinity chromatography

1998 ◽  
Vol 76 (8) ◽  
pp. 1109-1118 ◽  
Author(s):  
France-Isabelle Auzanneau ◽  
Mette Knak Christensen ◽  
Shannon L Harris ◽  
Morten Meldal ◽  
B Mario Pinto
Keyword(s):  
Polyethylene Glycol ◽  
Radical Copolymerization ◽  
Cross Linking ◽  
Carbohydrate Binding ◽  
Streptococcus Group ◽  
Group A ◽  
Carbohydrate Ligands ◽  
Immunoaffinity Columns ◽  
Cross Linker

The PEGA resin, a beaded polyethylene glycol dimethylacrylamide copolymer, was evaluated as an affinity support for the purification of carbohydrate-binding macromolecules, namely, the cation-independent mannosyl phosphate receptor (CI-MPR) and a polyclonal antibody directed against a Streptococcus Group A oligosaccharide. Two polyethylene glycol (PEG) derivatives, a di-acryloylated PEG1900derivative or a longer di-acryloylated PEG4000derivative, were used as cross-linkers. The longer cross-linker was synthesized in four steps from polyethylene glycol 4000. The mannosyl 6-phosphate (M6P)-containing immunoaffinity columns were prepared through the inverse suspension radical copolymerization of the corresponding allyl glycoside with acrylamide and the PEG cross-linker. The resin with the shorter cross-linker (PEG1900derivative) had a 6.3% molar cross-linking while that with the longer cross-linker (PEG4000derivative) had a 3.8% molar cross-linking. For the Streptococcus Group A trisaccharide-containing immunoaffinity columns, three PEGA affinity supports bearing free amino groups were prepared and subsequently substituted with a trisaccharide activated as its squarate adduct. While one resin contained the shorter cross-linker PEG1900and had a 3% molar cross-linking, the other two resins contained the longer cross-linker PEG4000 with a molar cross-linking of 5% and 3%, respectively. In affinity chromatographic studies, the M6P-containing columns were ineffective in retaining the cation-independent mannosyl phosphate receptor (CI-MPR, ~ 215kDa), whereas antibody (~ 150kDa) retention was observed with two of the three Streptococcus Group A trisaccharide-containing immunoaffinity columns. Key words: PEGA resins, immunoaffinity supports, carbohydrate ligands, antibody purification.

scholarly journals Toward Physicochemical and Rheological Characterization of Different Injectable Hyaluronic Acid Dermal Fillers Cross-Linked with Polyethylene Glycol Diglycidyl Ether

Polymers ◽  
2021 ◽  
Vol 13 (6) ◽  
pp. 948
Author(s):  
Nicola Zerbinati ◽  
Sabrina Sommatis ◽  
Cristina Maccario ◽  
Maria Chiara Capillo ◽  
Giulia Grimaldi ◽  
...  
Keyword(s):  
Hyaluronic Acid ◽  
Polyethylene Glycol ◽  
Biological Activities ◽  
Diglycidyl Ether ◽  
Dermal Filler ◽  
Cross Linking ◽  
Matrix Structure ◽  
Dermal Fillers ◽  
Rheological Characterization

(1) Background: Injectable hyaluronic acid (HA) dermal fillers are used to restore volume, hydration and skin tone in aesthetic medicine. HA fillers differ from each other due to their cross-linking technologies, with the aim to increase mechanical and biological activities. One of the most recent and promising cross-linkers is polyethylene glycol diglycidyl ether (PEGDE), used by the company Matex Lab S.p.A., (Brindisi, Italy) to create the HA dermal filler PEGDE family. Over the last few years, several studies have been performed to investigate the biocompatibility and biodegradability of these formulations, but little information is available regarding their matrix structure, rheological and physicochemical properties related to their cross-linking technologies, the HA content or the degree of cross-linking. (2) Methods: Seven different injectable HA hydrogels were subjected to optical microscopic examination, cohesivity evaluation and rheological characterization in order to investigate their behavior. (3) Results: The analyzed cross-linked dermal fillers showed a fibrous “spiderweb-like” matrix structure, with each medical device presenting different and peculiar rheological features. Except for HA non cross-linked hydrogel 18 mg/mL, all showed an elastic and cohesive profile. (4) Conclusions: The comparative analysis with other literature works makes a preliminary characterization of these injectable medical devices possible.

Polyacryloyl hydrazide based injectable & stimuli responsive hydrogels with tunable properties

2014 ◽  
Vol 2 (42) ◽  
pp. 7429-7439 ◽  
Author(s):  
Anuj Kumar ◽  
Sabindra K. Samal ◽  
Rupesh Dash ◽  
Umaprasana Ojha
Keyword(s):  
Polyethylene Glycol ◽  
Acrylic Acid ◽  
Diethyl Malonate ◽  
Synthesis And Characterization ◽  
Cross Linking ◽  
Stimuli Responsive ◽  
Polyethylene Glycol Diacrylate ◽  
Glycol Diacrylate ◽  
Responsive Hydrogels

The synthesis and characterization of a series of injectable and stimuli responsive hydrogels based on polyacryloyl hydrazide have been accomplished using dimethyl 2,2′-thiodiacetate, acrylic acid, diethyl malonate and polyethylene glycol diacrylate as cross-linkers through a chemical or dual cross-linking pathway.

Obtention and Characterization of Collagen and Chitosan Based Cements for Bone Regerneration. Part 1: Extraction and Characterization of Collagen

2014 ◽  
Vol 775-776 ◽  
pp. 29-33 ◽  
Author(s):  
Karine Cappucio de Castro ◽  
Ivan Silva Prado ◽  
Moacyr Clemente Júnior ◽  
Sylma Carvalho Maestrelli ◽  
Neide Aparecida Mariano ◽  
...  
Keyword(s):  
Cross Linking ◽  
Infrared Analysis ◽  
Fiber Structure ◽  
Cross Link ◽  
Scanning Calorimetry ◽  
High Mechanical Strength ◽  
Structure Characteristics ◽  
Cross Linker ◽  
High Degree

Several cements are used as biomaterials. Biopolymers such as chitosan and collagen exhibit excellent biocompatibility and can be used in the remodeling of bone tissue. The cement must have high mechanical strength and compatibility with original tissue. In this context, the objective of this study was to extract, characterize and cross-link collagen from bovine tendon, forlater associate it with chitosan and calcium phosphate to obtain cements for bone regeneration. Glutaraldehyde was used as cross-linker in 0.1, 0.5, 1.0 and 10% concentration. Infrared analysis confirmed the presence of functional groups characteristic of collagen, whereas the capacity of water absorption decreased with the increasing of cross-linking degree. Denaturation temperatures of collagen samples were obtained by Differential Scanning Calorimetry and Scanning Electron Microscopy showed the fiber structure characteristics of collagen, which were more organized for high degree of cross-linking samples.

Preparation and Characterization of Elastomers Based on Polydimethylsiloxane/Poly(methyl methacrylate) Blends

2012 ◽  
Vol 535-537 ◽  
pp. 1193-1196
Author(s):  
Nai Qiang Zhang ◽  
Jian Dong ◽  
Hong Yu Chen
Keyword(s):  
Methyl Methacrylate ◽  
Room Temperature ◽  
Radical Copolymerization ◽  
Cross Linking ◽  
Scanning Calorimetry ◽  
Silicone Elastomers ◽  
Poly Methyl Methacrylate ◽  
Dsc Measurements ◽  
Pmma Blends

Polydimethylsiloxane/poly (methyl methacrylate) (PDMS/PMMA) blends were prepared by radical copolymerization of methyl methacrylate (MMA) and divinylbenzene (DVB) in the presence of PDMS. Elastomers based on PDMS/PMMA blends were formed by cross-linking PDMS with methyltriethoxysilane (MTES). Mechanical property measurements show that the elastomers thus formed exhibit superior tensile strength with respect to general room temperature vulcanized silicone elastomers containing silica. Moreover, investigations were carried out on the elastomers by extraction, scanning electron microscopy (SEM) and differential scanning calorimetry (DSC) measurements. SEM shows that the elastomer has a microphase-separated structure consisting of dispersed PMMA domains within a continuous PDMS matrix. DSC result shows that the elastomers display two glass transition temperatures and confirm the incompatible nature of PDMS and PMMA.

scholarly journals Synthesis and Characterization of Room Temperature Vulcanized Silicone Rubber Using Methoxyl-Capped MQ Silicone Resin as Self-Reinforced Cross-Linker

Polymers ◽  
2019 ◽  
Vol 11 (7) ◽  
pp. 1142 ◽  
Author(s):  
Jianye Ji ◽  
Xin Ge ◽  
Xiaoyan Pang ◽  
Ruoling Liu ◽  
Shuyi Wen ◽  
...  
Keyword(s):  
Silicone Rubber ◽  
Room Temperature ◽  
Degradation Rate ◽  
Light Transmission ◽  
Characteristic Temperature ◽  
Cross Linking ◽  
Silicone Resin ◽  
Cross Linker ◽  
Rtv Silicone Rubber

Methoxyl-capped MQ silicone resin (MMQ) was first synthesized by the hydrosilylation of vinyl-containing MQ silicone resin and trimethoxysilane and then used in condensed room-temperature vulcanized (RTV) silicone rubber as a self-reinforced cross-linker. Results show that modified silicone rubber exhibits good light transmission. Compared with unmodified silicone rubber, the hardness, tensile strength and elongation of MMQ at the break are increased by 26.4 A, 2.68 MPa and 65.1%, respectively. In addition, the characteristic temperature of 10% mass loss is delayed from 353.5 °C to 477.1 °C, the temperature at maximum degradation rate is also delayed from 408.9 °C to 528.4 °C and the residual mass left at 800 °C is increased from 1.2% to 27.7%. These improved properties are assigned to the synergistic effect of the rigid structure of MMQ, the formation of a dense cross-linking structure in polymers and the uniform distribution of MMQ cross-linking agent in RTV silicone rubber.

scholarly journals Electron Beam Synthesis and Characterization of Acrylamide/Acrylic Acid Hydrogels Using Trimethylolpropane Trimethacrylate as Cross-Linker

2016 ◽  
Vol 2016 ◽  
pp. 1-14 ◽  
Author(s):  
Gabriela Craciun ◽  
Elena Manaila ◽  
Maria Daniela Stelescu
Keyword(s):  
Electron Beam ◽  
Acrylic Acid ◽  
Dose Range ◽  
Absorbed Dose ◽  
Radical Copolymerization ◽  
Synthesis And Characterization ◽  
Free Radical Copolymerization ◽  
Swelling Properties ◽  
Cross Linker

The purpose of the paper is to present the synthesis and characterization of hydrogels prepared by free-radical copolymerization of acrylamide and acrylic acid in aqueous solutions using potassium persulfate as initiator and trimethylolpropane trimethacrylate as cross-linker, via the radiation technique. The samples were subjected to electron beam treatment in the dose range of 2 to 4 kGy and the influence of the absorbed dose and amount of cross-linker on the swelling properties, diffusion coefficient, and network parameters of hydrogels was investigated. A possible reaction mechanism for acrylamide/acrylic acid/trimethylolpropane trimethacrylate hydrogels was also suggested. The structure and morphology of hydrogels were characterized by Fourier Transform Infrared Spectroscopy and Scanning Electron Microscopy.

scholarly journals Xylan-Based Hydrogels as a Potential Carrier for Drug Delivery: Effect of Pore-Forming Agents

Pharmaceutics ◽  
2018 ◽  
Vol 10 (4) ◽  
pp. 261 ◽  
Author(s):  
Minmin Chang ◽  
Xinxin Liu ◽  
Ling Meng ◽  
Xiaohui Wang ◽  
Junli Ren
Keyword(s):  
Drug Delivery ◽  
Polyethylene Glycol ◽  
Drug Release ◽  
Pore Structure ◽  
Significant Influence ◽  
Radical Copolymerization ◽  
Cross Linking ◽  
Swelling Ratio ◽  
Model Drug ◽  
Carboxymethyl Xylan

Pore-forming agents have a significant influence on the pore structure of hydrogels. In this study, a porogenic technique was employed to investigate the preparation of macroporous hydrogels which were synthesized by radical copolymerization of carboxymethyl xylan with acrylamide and N-isopropylacrylamide under the function of a cross-linking agent. Six kinds of pore-forming agents were used: polyvinylpyrrolidone K30, polyethylene glycol 2000, carbamide, NaCl, CaCO3, and NaHCO3. The application of these hydrogels is also discussed. The results show that pore-forming agents had an important impact on the pore structure of the hydrogels and consequently affected properties of the hydrogels such as swelling ratio and mechanical strength, while little effect was noted on the thermal property of the hydrogels. 5-Fluorouracil was used as a model drug to study the drug release of the as-prepared hydrogels, and it was found that the drug release was substantially improved after using the NaHCO3 pore-forming agent: a cumulative release rate of up to 71.05% was achieved.

Tonsillar Inflammation, a Rare Cause of Bradycardia and Hypotension

2018 ◽  
Vol 3 (3) ◽  
Keyword(s):  
Streptococcus Pyogenes ◽  
Fusobacterium Necrophorum ◽  
Outpatient Setting ◽  
Peritonsillar Abscess ◽  
The Other ◽  
Streptococcus Group ◽  
Other Hand ◽  
Group A

Tonsillitis is a frequently encountered pathology in the outpatient setting, usually caused by viruses [1]. When bacterial, the most common causatory microbe is streptococcus group A [1]. Tonsillar and peritonsillar abscess (PTA) on the other hand are never viral, and are usually caused by streptococcus pyogenes, Streptococcus melleri, fusobacterium necrophorum and staphylococci [1,2]. The overall incidence of PTA is suggested to be 37/100,000 patients, with the highest incidence between ages 14-21 at 124/100,000 [3].

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