Synthesis and Application of New Photocrosslinkers for Poly(ethylene glycol)

2012 ◽  
Vol 65 (2) ◽  
pp. 193 ◽  
Author(s):  
Hakim Mehenni ◽  
Vincent Pourcelle ◽  
Jean-François Gohy ◽  
Jacqueline Marchand-Brynaert
Keyword(s):  
Polyethylene Glycol ◽  
Ethylene Glycol ◽  
Functional Polymers ◽  
Size Exclusion ◽  
Poly Ethylene Glycol ◽  
Polymer Backbone ◽  
Exclusion Chromatography ◽  
Exogenous Agents ◽  
Commercial Sources ◽  
Poly Ethylene

Photocrosslinking of polyethylene glycol (PEG) using exogenous agents is a convenient way to produce branched PEG from commercial sources thus avoiding the tricky synthesis of new reactive and functional polymers. In this study, we synthesized two series of new photocrosslinkers, i.e. bis-fluorophenyl azide and bis-trifluoromethyl diazirine, which under soft UV-irradiation produce reactive species (i.e. nitrene and carbene respectively) that insert into the C–H bond of the polymer backbone, building new bridges between macromolecular chains. These photocrosslinkers are different in terms of behaviour under irradiation and affinity for the target substrate (i.e. PEG). Thus, practical conditions for photocrosslinking of a 10-kDa PEG were studied and followed by NMR and size-exclusion chromatography. In particular, we investigated irradiation in bulk or in solvent, at different irradiation times, with several concentrations of PEG and photolinkers. Finally, we were able to design a procedure to obtain soluble crosslinked PEGs of 300 kDa.

Tracing the transport of organic colloids in porous media using tailored poly(ethylene glycol)

2021 ◽  
Author(s):  
Thomas Ritschel ◽  
Katharina Lehmann ◽  
Michaela Brunzel ◽  
Jürgen Vitz ◽  
Ivo Nischang ◽  
...  
Keyword(s):  
Porous Media ◽  
Ethylene Glycol ◽  
Water Solubility ◽  
Size Range ◽  
Large Fraction ◽  
Colloid Interface ◽  
Poly Ethylene Glycol ◽  
Polymer Backbone ◽  
Colloidal Transport ◽  
Poly Ethylene

<p>A large fraction of organic matter in natural aqueous soil solutions is given by molecules in sizes above one nanometer, which classifies them as colloids according to the IUPAC definition. Such colloids feature discernable mobility in soils and their transport is decisive for the cycling of carbon as well as the migration of nutrients or contaminants. Yet, their size-dependent hydrodynamics and functional diversity result in transport phenomena that are specific to colloids and, thus, largely differ from those observed for smaller substances. Still, tracers that appropriately represent small organic colloids are not available and the investigation of their transport in laboratory column experiments, in dependence of size and chemistry, remains difficult. To overcome this limitation, we tested if well-defined synthetic polymers in the colloidal size range are suitable as non-conventional tracers of colloidal transport. As polymer backbone, we selected poly(ethylene glycol) (PEG) due to its high water-solubility and established pathway of synthesis that permits tailoring of functional moieties to the fullest extent. An easy and sensitive detection in the aqueous phase became possible by using a fluorophore as starting group. After full characterization, we studied PEG adsorption to quartz, illite, goethite, and their mixtures in batch and column transport experiments. In numerical simulations, we successfully reconstructed and predicted PEG transport based on its physicochemical as well as hydrodynamic properties and, thus, show that PEG transport can be comprehensively and quantitatively studied. Considering also its low adverse effect on the environment, functional PEG therefore presents as promising candidate to be used as organic tracer, designable in the size range of natural organic (macro-)molecules (Ritschel et al., 2021).</p><p>References</p><p>Ritschel, T., Lehmann, K., Brunzel, M., Vitz, J., Nischang, I., Schubert, U., Totsche, K. U. (2021) <strong>Well-defined poly(ethylene glycol) polymers as non-conventional reactive tracers of colloidal transport in porous media</strong>.<em> J. Colloid Interface Sci.</em> 548, 592-601, doi: 10.1016/j.jcis.2020.09.056.</p>

scholarly journals Some Guidelines for the Synthesis and Melting Characterization of Azide Poly(ethylene glycol) Derivatives

Polymers ◽  
2020 ◽  
Vol 12 (6) ◽  
pp. 1269
Author(s):  
Daniel González-Fernández ◽  
Mercedes Torneiro ◽  
Massimo Lazzari
Keyword(s):  
Molecular Weight ◽  
Ethylene Glycol ◽  
Average Molecular Weight ◽  
Size Exclusion ◽  
Degree Of Crystallinity ◽  
Specific Class ◽  
Poly Ethylene Glycol ◽  
End Groups ◽  
Poly Ethylene

We provide fundamental guidelines in the form of a tutorial to be taken into account for the preparation and characterization of a specific class of poly(ethylene glycol) (PEG) derivatives, namely azide-terminated PEGs. Special attention is given to the effect of these chain end groups and their precursors on properties affecting the PEGylation of proteins, nanoparticles and nanostructured surfaces. Notwithstanding the presence of 13C satellite peaks, we show that 1H NMR enables not only the routine quantitative determination of chain-end substitution, but is also a unique method to calculate the absolute number average molecular weight of PEG derivatives. In the use of size exclusion chromatography to get molecular weight distributions, we highlight the importance of distinguishing between eventual secondary reactions involving molecular weight changes and the formation of PEG complexes due to residual amounts of metal cations from reactants. Finally, we show that azide end groups affect PEG melting behavior. In contrast to oxygen-containing end groups, azides do not interact with PEG segments, thus inducing defect formation in the crystal lattice and the reduction of crystal sizes. Melting temperature and degree of crystallinity decrease become especially relevant for PEGs with very low molecular weight, and its comprehension is particularly important for solid-state applications.

Mechanical properties and hydrolytic degradation of methoxy poly(ethylene glycol)-b-poly(DL-lactide-coglycolide- co-ε-caprolactone) diblock copolymer films

e-Polymers ◽  
2008 ◽  
Vol 8 (1) ◽  
Author(s):  
Nongnit Morakot ◽  
Jirasak Threeprom ◽  
Yodthong Baimark
Keyword(s):  
Mechanical Properties ◽  
Weight Loss ◽  
Ethylene Glycol ◽  
Diblock Copolymers ◽  
Hydrolytic Degradation ◽  
Size Exclusion ◽  
Block Length ◽  
Poly Ethylene Glycol ◽  
Scanning Calorimetry ◽  
Poly Ethylene

AbstractBiodegradable films of methoxy poly(ethylene glycol)-b-poly(DL-lactideco- glycolide-co-ε-caprolactone) diblock copolymers (MPEG-b-PDLLGCL) were prepared by solution casting method. Effects of MPEG block length and DLL:G:CL ratio of the MPEG-b-PDLLGCL films on their mechanical properties and hydrolytic degradation were studied and discussed. It was found that the mechanical properties of films were strongly dependent on glass transition temperatures (Tg) of the diblock copolymers. The hydrolytic degradation was investigated in phosphatebuffered solution at 37°C. The degraded films were characterized using gravimetry (%water uptake and %weight loss), 1H-NMR spectroscopy, differential scanning calorimetry and size exclusion chromatography. The %weight loss of the degraded films increased and molecular weight decreased on increasing the MPEG block length and incorporating the G and CL units, according to their %water uptakes. The MPEG content of the degraded film decreased and the Tg increased with hydrolytic degradation time.

Reappearance of slow mode in mixtures of polyethylene glycol and poly(sodium methacrylate)

Soft Matter ◽  
2018 ◽  
Vol 14 (24) ◽  
pp. 5039-5047
Author(s):  
Ksenija Kogej ◽  
Jaka Štirn ◽  
Jurij Reščič
Keyword(s):  
Polyethylene Glycol ◽  
Light Scattering ◽  
Dynamic Light Scattering ◽  
Ethylene Glycol ◽  
Slow Mode ◽  
Poly Ethylene Glycol ◽  
Poly Ethylene ◽  
Scattering Signal ◽  
Sodium Methacrylate

After addition of poly(ethylene glycol) to a solution of poly(sodium methacrylate), the slow-mode dynamic light scattering signal reappears.

Alternative polymer precipitants for protein crystallization

2010 ◽  
Vol 43 (4) ◽  
pp. 737-742 ◽  
Author(s):  
Tereza Skálová ◽  
Jarmila Dušková ◽  
Jindřich Hašek ◽  
Petr Kolenko ◽  
Andrea Štěpánková ◽  
...  
Keyword(s):  
Polyethylene Glycol ◽  
Ethylene Glycol ◽  
Protein Crystallization ◽  
Glycol Adipate ◽  
Poly Ethylene Glycol ◽  
Ph Values ◽  
Ethylene Glycol Adipate ◽  
Acid Sodium Salt ◽  
Poly Ethylene ◽  
Glycol Methyl Ether

A set of 16 inexpensive and commercially available polymer precipitants were tested for protein crystallization. Eight of them were found suitable: polyethylene glycol dimethyl ether of molecular weight (MW) 500, 1000 and 2000; di[poly(ethylene glycol)] adipate, MW 900; poly(ethylene glycol-ran-propylene glycol), MW 2500 and 12000; poly(acrylic acid) sodium salt, MW 2100; and polyethylene glycol methyl ether methacrylate, MW 1100. Two new crystallization screens, PolyA and PolyB, were formulated using these eight polymers, each containing 96 solutions – four polymers in combination with 24 common salts and buffers, covering pH values from 4.5 to 9.0. The screens were tested on 29 proteins, 21 of which were crystallized. The tests confirmed the applicability of the eight polymers as precipitants for protein crystallization.

scholarly journals MoS2 QDs/8-Armed Poly(Ethylene Glycol) Fluorescence Sensor for Three Nitrotoluenes (TNT) Detection

Biosensors ◽  
2021 ◽  
Vol 11 (12) ◽  
pp. 475
Author(s):  
Xiaoyuan Zhang ◽  
Zhiqiang Su
Keyword(s):  
Quantum Dots ◽  
Polyethylene Glycol ◽  
Detection Limit ◽  
Ethylene Glycol ◽  
Hydrazine Hydrate ◽  
Poly Ethylene Glycol ◽  
Fluorescent Properties ◽  
Detection Range ◽  
Poly Ethylene ◽  
Tnt Detection

In this work, ammonia cross-linked 8-armed polyethylene glycol hydrogel material was successfully synthesized and used as a template for synthesizing nanoparticles with fluorescent properties. The 8-armed polyethylene glycol hydrogel template was used to prepare molybdenum disulfide quantum dots (MoS2 QDs). The ammonium tetrathiomolybdate functioned as a molybdenum source and hydrazine hydrate functioned as a reducing agent. The fluorescence properties of the as-prepared MoS2 QDs were investigated. The bursting of fluorescence caused by adding different concentrations of explosive TNT was studied. The study indicated that the synthesized MoS2 QDs can be used for trace TNT detection with a detection limit of 6 nmol/L and a detection range of 16–700 nmol/L. Furthermore, it indicated that the fluorescence-bursting mechanism is static bursting.

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