- Synthesis of Linear High Molar Mass Glycidol-Based Polymers by Monomer-Activated Anionic Polymerization
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Linear polyglycidols of high molar masses were prepared by the monomer-activated anionic polymerization of the corresponding protected monomers, ethoxyethyl glycidyl ether and tert-butyl glycidyl ether, using a system composed of tetraoctylammonium bromide as initiator and triisobutylaluminum as monomer activator. The aluminic compound was used in 1.5-5-fold excess compared to the initiator. Linear poly(ethoxyethyl glycidyl ether) and poly(teri-butyl glycidyl ether), with narrow chain dispersity and controlled high molar masses, up to 85 000 g/mol, were prepared at 0 °C in a few hours. Deprotection of hydroxyl functions by acidic treatment of the polymers was shown to proceed quantitatively and cleanly affording the corresponding linear polyglycerol and validating the use of these protecting groups. The copolymerization of protected glycidols with propylene oxide and butene oxide was also investigated with the goal to broaden the scope of this synthetic approach to various polyethers and copolyethers.
- Gervais, Matthieu,Brocas, Anne-Laure,Cendejas, Gabriel,Deffieux, Alain,Carlotti, Stephane
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- Hyperbranched molecular nanocapsules: Comparison of the hyperbranched architecture with the perfect linear analogue
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The results of a comparative study of hyperbranched, partially esterified polyglycerols with their linear polyglycerol analogues with respect to molecular encapsulation and phase transfer are reported. Two hyperbranched polyglycerol samples with molecular weights of 3000 and 8000 g/mol (Mw/Mn = 1.3), respectively, have been partially esterified using palmitoyl chloride. The same modification was applied to the structurally analogous linear polyglycerol (3000 g/mol). A detailed UV-vis study correlated with viscosity experiments demonstrated that only the hyperbranched core-shell structures form "nanocapsules", leading to the encapsulation of polar guest molecules. The results underline the crucial role of the hyperbranched topology and the resulting solution conformation for supramolecular guest encapsulation and phase transfer. The unusually compact ("collapsed") structure assumed by the hyperbranched core-shell amphiphiles in apolar media is responsible for the formation of a hydrophilic compartment, capable of irreversibly taking up guest molecules. Copyright
- Stiriba, Salah-Eddine,Kautz, Holger,Frey, Holger
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- TGF-β1-Modified Hyaluronic Acid/Poly(glycidol) Hydrogels for Chondrogenic Differentiation of Human Mesenchymal Stromal Cells
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In cartilage regeneration, the biomimetic functionalization of hydrogels with growth factors is a promising approach to improve the in vivo performance and furthermore the clinical potential of these materials. In order to achieve this without compromising network properties, multifunctional linear poly(glycidol) acrylate (PG-Acr) is synthesized and utilized as crosslinker for hydrogel formation with thiol-functionalized hyaluronic acid via Michael-type addition. As proof-of-principle for a bioactivation, transforming growth factor-beta 1 (TGF-β1) is covalently bound to PG-Acr via Traut's reagent which does not compromise the hydrogel gelation and swelling behavior. Human mesenchymal stromal cells (MSCs) embedded within these bioactive hydrogels show a distinct dose-dependent chondrogenesis. Covalent incorporation of TGF-β1 significantly enhances the chondrogenic differentiation of MSCs compared to hydrogels with supplemented noncovalently bound TGF-β1. The observed chondrogenic response is similar to standard cell culture with TGF-β1 addition with each medium change. In general, multifunctional PG-Acr offers the opportunity to introduce a range of biomimetic modifications (peptides, growth factors) into hydrogels and, thus, appears as an attractive potential material for various applications in regenerative medicine.
- B?ck, Thomas,Schill, Verena,Kr?hnke, Martin,Steinert, Andre F.,Tessmar, J?rg,Blunk, Torsten,Groll, Jürgen
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- Synthesis of novel glycidol copolymers with pendant alkene and hydroxyl groups
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A series of linear poly glycidol copolymers, tethering with both alkene and hydroxyl groups, were prepared by a combination of anionic ring-opening polymerization (ROP) using specific reactions of ethoxy ethyl glycidyl ether (EEGE) and allyl glycidyl ether (AGE) firstly, and subsequently removal of the protection group of glycidol in EEGE to achieve the linear copolymer pendant with both hydroxyl groups and double bonds. The EEGE/AGE monomer reactivity ratio is measured to be 3.30/1.13. The chemical compositions of the as-synthesized polymers were characterized by 1H NMR and GPC, and the glass transition temperatures (Tg) of as-synthesized polymers were determined by DSC. The final copolymers have abundant double bonds and hydroxyl as side groups. Furthermore, the ratio of the double bonds to hydroxyl groups can be controlled by the ratio of the starting materials in a wide range. A facile method is presented here to synthesize glycidol copolymers pendant with multiple different functional groups at a time, which has a potential application for further chemical modification and functionalization. Copyright
- Liu, Siwei,Zhang, Feng,Zhang, Yi,Xu, Jiarui
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- A pH-and temperature-sensitive macrocyclic graft copolymer composed of PEO ring and multi-poly(2-(dimethylamino) ethyl methacrylate) lateral chains
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A novel method for the synthesis of macrocyclic graft copolymers was developed through combination of anionic ring-opening polymerization (AROP) and atom transfer radical polymerization (ATRP). A linear α,ω-dihydroxyl poly(ethylene oxide) with pendant acetal protected hydroxyl groups (l-poly(EO-co-EEGE)) was prepared first by the anionic copolymerization of ethylene oxide (EO) and ethoxyethyl glycidyl ether (EEGE). Then l-poly(EO-co-EEGE) was cyclized. The crude cyclized product containing the linear byproduct was hydrolyzed and purified by being treated with α-CD. The pure cyclic copolymer [c-poly(EO-co-Gly)] was esterified by reaction with 2-bromoisobutyryl bromide, and then used as ATRP macroinitiators to initiate polymerization of 2-(dimethylamino) ethyl methacrylate (DMAEMA), and a series of pH-and temperature-sensitive macrocyclic graft copolymers composed of a hydrophilic PEO as the ring and PDMAEMA as side chains (c-PEO-g-PDMAEMA) were obtained. The behavior of pH-and temperature-sensitive macrocyclic copolymers was studied in aqueous solution by fluorescence and dynamic light scattering (DLS). The critical micellization pH values of macrocyclic graft copolymers and their corresponding linear graft copolymers (l-PEO-g-PDMAEMA) were measured. Under the same conditions, the cyclic graft copolymer with the shorter side chains gave the higher critical micellization pH value. The c-PEO-g-PDMAEMA showed the lower critical micellization pH value than the corresponding l-PEO-g-PDMAEMA. The average hydrodynamic diameters (Dh) of the micelles were measured by DLS with the variation of the aqueous solution pH value and temperature. Science China Press and Springer-Verlag Berlin Heidelberg 2010.
- Pang, Xinchang,Jing, Rongkuan,Pan, Mugang,Huang, Junlian
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- Hyperbranched double hydrophilic block copolymer micelles of poly(ethylene oxide) and polyglycerol for pH-responsive drug delivery
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We report the synthesis of a well-defined hyperbranched double hydrophilic block copolymer of poly-(ethylene oxide)-hyperbranched-polyglycerol (PEO-hb-PG) to develop an efficient drug delivery system. In specific, we demonstrate the hyperbranched PEO-hb-PG can form a selfassembled micellar structure on conjugation with the hydrophobic anticancer agent doxorubicin, which is linked to the polymer by pH-sensitive hydrazone bonds, resulting in a pHresponsive controlled release of doxorubicin. Dynamic light scattering, atomic force microscopy, and transmission electron microscopy demonstrated successful formation of the spherical core-shell type micelles with an average size of about 200 nm. Moreover, the pH-responsive release of doxorubicin and in vitro cytotoxicity studies revealed the controlled stimuli-responsive drug delivery system desirable for enhanced efficiency. Benefiting from many desirable features of hyperbranched double hydrophilic block copolymers such as enhanced biocompatibility, increased water solubility, and drug loading efficiency as well as improved clearance of the polymer after drug release, we believe that double hydrophilic block copolymer will provide a versatile platform to develop excellent drug delivery systems for effective treatment of cancer.
- Lee, Sueun,Saito, Kyohei,Lee, Hye-Ra,Lee, Min Jae,Shibasaki, Yuji,Oishi, Yoshiyuki,Kim, Byeong-Su
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- Functional Isoeugenol-Modified Nanogel Coatings for the Design of Biointerfaces
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A new route for the synthesis of functional aqueous nanogels decorated with a controlled amount of surface-drafted isoeugenol molecules has been developed. Obtained nanogels exhibit two key functions: a) antibacterial activity against different oral pathogens and b) cell-adhesive and -growth-promoting properties. Functional nanogels can be potentially used as building blocks in the design of bioactive coatings on various implants preventing infections and accelerating tissue regeneration.
- Kather, Michael,Skischus, Merle,Kandt, Pierre,Pich, Andrij,Conrads, Georg,Neuss, Sabine
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- Inhibition of Herpes Simplex Virus Type 1 Attachment and Infection by Sulfated Polyglycerols with Different Architectures
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Inhibition of herpes simplex virus type 1 (HSV-1) binding to the host cell surface by highly sulfated architectures is among the promising strategies to prevent virus entry and infection. However, the structural flexibility of multivalent inhibitors plays a major role in effective blockage and inhibition of virus receptors. In this study, we demonstrate the inhibitory effect of a polymer scaffold on the HSV-1 infection by using highly sulfated polyglycerols with different architectures (linear, dendronized, and hyperbranched). IC50 values for all synthesized sulfated polyglycerols and the natural sulfated polymer heparin were determined using plaque reduction infection assays. Interestingly, an increase in the IC50 value from 0.03 to 374 nM from highly flexible linear polyglycerol sulfate (LPGS) to less flexible scaffolds, namely, dendronized polyglycerol sulfate and hyperbranched polyglycerol sulfate was observed. The most potent LPGS inhibits HSV-1 infection 295 times more efficiently than heparin, and we show that LPGS has a much reduced anticoagulant capacity when compared to heparin as evidenced by measuring the activated partial thromboplastin time. Furthermore, prevention of infection by LPGS and the commercially available drug acyclovir were compared. All tested sulfated polymers do not show any cytotoxicity at concentrations of up to 1 mg/mL in different cell lines. We conclude from our results that more flexible polyglycerol sulfates are superior to less flexible sulfated polymers with respect to inhibition of HSV-1 infection and may constitute an alternative to the current antiviral treatments of this ubiquitous pathogen.
- Pouyan, Paria,Nie, Chuanxiong,Bhatia, Sumati,Wedepohl, Stefanie,Achazi, Katharina,Osterrieder, Nikolaus,Haag, Rainer
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p. 1545 - 1554
(2021/04/05)
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- POLYMER PARTICLES AND BIOMATERIALS COMPRISING THE SAME
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The present invention relates to polymer particles comprising antibiotics which are deliverable in situ, as well as a method of preparation thereof. The present invention also relates to bioactive biomaterials for the controlled delivery of antibiotics comprising support materials having such polymer particles on their surface. The invention also relates to implants, prostheses, stents, lenses or cements as well as any pharmaceutical composition comprising said biomaterials.
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Paragraph 0116-0119
(2018/01/18)
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- SUNSCREEN COMPOSITIONS CONTAINING A COMBINATION OF A LINEAR ULTRAVIOLET RADIATION-ABSORBING POLYETHER AND OTHER ULTRAVIOLET-SCREENING COMPOUNDS
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Sunscreen composition including a combination of a linear ultraviolet radiation absorbing polyether that includes a covalently bound UV-chromophore, and at least one non-polymeric UV-screening compounds.
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Page/Page column 36; 37
(2018/02/24)
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- Ultraviolet radiation absorbing polyethers
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A polymer composition comprising a linear ultraviolet radiation absorbing polyether that comprises a chemically bound UV-chromophore.
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Page/Page column 12; 13
(2016/03/06)
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- LINEAR POLYESTER AND SEMI-LINEAR GLYCIDOL POLYMER SYSTEMS: FORMULATION AND SYNTHESIS OF NOVEL MONOMERS AND MACROMOLECULAR STRUCTURES
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Disclosed herein are glycidol-based polymers, nanoparticles, and methods related thereto useful for drug delivery. This abstract is intended as a scanning tool for purposes of searching in the particular art and is not intended to be limiting of the present invention.
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Paragraph 0294
(2014/02/15)
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- SUNSCREEN COMPOSITIONS CONTAINING AN ULTRAVIOLET RADIATION-ABSORBING POLYMER
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Compositions including a discontinuous oil phase homogeneously dispersed in a continuous water phase, the oil phase containing a sunscreen agent that includes a polymer composition containing a linear, ultraviolet radiation absorbing polyether, the linear
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Paragraph 0097; 0098
(2014/02/15)
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- Multihydroxyl-functional polystyrenes in continuous flow
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We describe the synthesisof end-functionalized polystyrenes byliving anionic polymerization ina microstructured reactor via termination by acetal-protected functional epoxides. Initiation of styrene polymerization by alkyllithium takes place in a micromix
- Tonhauser, Christoph,Wilms, Daniel,Wurm, Frederik,Berger-Nicoletti, Elena,Maskos, Michael,Lowe, Holger,Frey, Holger
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experimental part
p. 5582 - 5588
(2011/10/12)
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- Synthesis of Simple Oxetanes Carrying Reactive 2-Substituents
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Ring-expansion of substituted epoxides using dimethyloxosulphonium methylide provides a convenient route to oxetanes carrying reactive 2-substituents that are capable of further modification.
- Fitton, Alan O.,Hill, John,Jane, David E.,Millar, Ross
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p. 1140 - 1142
(2007/10/02)
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