| 1. |
- Andrén, Oliver C. J., et al.
(författare)
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Antibiotic-Free Cationic Dendritic Hydrogels as Surgical-Site-Infection-Inhibiting Coatings
- 2019
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Ingår i: Advanced Healthcare Materials. - : Wiley. - 2192-2640 .- 2192-2659.
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Tidskriftsartikel (refereegranskat)abstract
- A non-toxic hydrolytically fast-degradable antibacterial hydrogel is herein presented to preemptively treat surgical site infections during the first crucial 24 h period without relying on conventional antibiotics. The approach capitalizes on a two-component system that form antibacterial hydrogels within 1 min and consist of i) an amine functional linear-dendritic hybrid based on linear poly(ethylene glycol) and dendritic 2,2-bis(hydroxymethyl)propionic acid, and ii) a di-N-hydroxysuccinimide functional poly(ethylene glycol) cross-linker. Broad spectrum antibacterial effect is achieved by multivalent representation of catatonically charged β-alanine on the dendritic periphery of the linear dendritic component. The hydrogels can be applied readily in an in vivo setting using a two-component syringe delivery system and the mechanical properties can accurately be tuned in the range equivalent to fat tissue and cartilage (G' = 0.5-8 kPa). The antibacterial effect is demonstrated both in vitro toward a range of relevant bacterial strains and in an in vivo mouse model of surgical site infection.
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| 2. |
- Arseneault, Mathieu, et al.
(författare)
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The Dawn of Thiol-Yne Triazine Triones Thermosets as a New Material Platform Suited for Hard Tissue Repair
- 2018
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Ingår i: Advanced Materials. - : Wiley. - 0935-9648 .- 1521-4095. ; 30:52
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Tidskriftsartikel (refereegranskat)abstract
- The identification of a unique set of advanced materials that can bear extraordinary loads for use in bone and tooth repair will inevitably unlock unlimited opportunities for clinical use. Herein, the design of high-performance thermosets is reported based on triazine-trione (TATO) monomers using light-initiated thiol-yne coupling (TYC) chemistry as a polymerization strategy. In comparison to traditional thiol-ene coupling (TEC) systems, TYC chemistry has yielded highly dense networks with unprecedented mechanical properties. The most promising system notes 4.6 GPa in flexural modulus and 160 MPa in flexural strength, an increase of 84% in modulus and 191% in strength when compared to the corresponding TATO system based on TEC chemistry. Remarkably, the mechanical properties exceed those of polylactide (PLA) and challenge poly(ether ether ketone) PEEK and today's methacrylate-based dental resin composites. All the materials display excellent biocompatibility, in vitro, and are successfully: i) molded into medical devices for fracture repair, and ii) used as bone adhesive for fracture fixation and as tooth fillers with the outstanding bond strength that outperform methacrylate systems used today in dental restoration application. Collectively, a new era of advanced TYC materials is unfolded that can fulfill the preconditions as bone fixating implants and for tooth restorations.
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| 3. |
- Erlandsson, Johan, et al.
(författare)
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On the mechanism behind freezing-induced chemical crosslinking in ice-templated cellulose nanofibril aerogels
- 2018
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Ingår i: Journal of Materials Chemistry A. - : Royal Society of Chemistry. - 2050-7488 .- 2050-7496. ; 6:40, s. 19371-19380
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Tidskriftsartikel (refereegranskat)abstract
- The underlying mechanism related to freezing-induced crosslinking of aldehyde-containing cellulose nanofibrils (CNFs) has been investigated, and the critical parameters behind this process have been identified. The aldehydes introduced by periodate oxidation allows for formation of hemiacetal bonds between the CNFs provided the fibrils are in sufficiently close contact before the water is removed. This is achieved during the freezing process where the cellulose components are initially separated, and the growth of ice crystals forces the CNFs to come into contact in the thin lamellae between the ice crystals. The crosslinked 3-D structure of the CNFs can subsequently be dried under ambient conditions after solvent exchange and still maintain a remarkably low density of 35 kg m-3, i.e. a porosity greater than 98%. A lower critical amount of aldehydes, 0.6 mmol g-1, was found necessary in order to generate a crosslinked 3-D CNF structure of sufficient strength not to collapse during the ambient drying. The chemical stability of the 3-D structure can be further enhanced by converting the hemiacetals to acetals by treatment with an alcohol under acidic conditions.
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| 4. |
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| 5. |
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| 6. |
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| 7. |
- Hern, Faye Y., et al.
(författare)
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Model studies of the sequential and simultaneous statistical modification of dendritic functional groups and their implications within complex polymer architecture synthesis
- 2017
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Ingår i: Polymer Chemistry. - : Royal Society of Chemistry. - 1759-9954 .- 1759-9962. ; 8:10, s. 1644-1653
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Tidskriftsartikel (refereegranskat)abstract
- Post-synthesis modification of polymers is a synthetically appealing approach to generate a range of samples from a single, well-characterised starting material. When partial or mixed-functionalisation is sought, an inevitable statistical distribution of modification outcomes will lead to considerable variation of chemical structures within the final sample. Here we have comprehensively investigated the postsynthesis sequential/partial and simultaneous mixed modification of xanthate-functional ideal dendrons and used this data to consider the implications for the more complex linear-dendritic hybrids and hyper-branched- polydendron analogues. Although H-1 NMR confirmed the potential to direct the reactions, it was clear from MALDI-TOF studies that very little of the actual targeted structures were generated in the statistical reactions.
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| 8. |
- Hult, Daniel, 1986-, et al.
(författare)
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Degradable High Tg Sugar Derived Polycarbonates from Isosorbide and Dihydroxyacetone
- 2018
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Ingår i: Polymer Chemistry. - : Royal Society of Chemistry. - 1759-9954 .- 1759-9962. ; 9:17, s. 2238-2246
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Tidskriftsartikel (refereegranskat)abstract
- Polycarbonates from isosorbide and dihydroxyacetone (DHA) have been synthesised using organocatalytic step-growth polymerization of their corresponding diols and bis-carbonylimidazolides monomers. By choice of feed ratio and monomer activation, either isosorbide or ketal protected DHA, random and alternating poly(Iso-co-DHA) carbonates have been formed. Thermal properties by DSC and TGA were herein strongly correlated to monomer composition. Dilution studies using 1H-NMR of a model compound DHA-diethyl carbonate in acetonitrile and deuterated water highlighted the influence of α-substituents on the keto/hydrate equilibrium of DHA. Further kinetics studies of in the pH* range of 4.7 to 9.6 serve to show the hydrolytic pH-profile of DHA-carbonates. The Hydrolytic degradation of deprotected polymer pellets show an increased degradation with increasing DHA content. Pellets with a random or alternating configuration show different characteristics in terms of mass loss and molecular weight loss profile over time.
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| 9. |
- Hult, Daniel, 1986-
(författare)
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Versatile Synthetic Strategies to Highly Functional Polyesters and Polycarbonates
- 2018
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Doktorsavhandling (övrigt vetenskapligt/konstnärligt)abstract
- Polymers have become ubiquitous in today’s society and are found in everything from household items to airplanes and automobiles. Synthetic polymeric materials are as diverse as their applications and their final properties are highly reliant on the building blocks and methods used to assemble them. In the field of biomedical materials, polyesters and polycarbonates have been hailed as excellent materials in large part due to their inherent hydrolytic degradability. With this in mind, careful choice of monomers can ensure that materials not only conform to the desired physical properties, but also elicit a favorable biological response. The utilization of post-polymerization modification of these promising materials has the capability of opening up further avenues to target even more advanced applications. Unfortunately, rigorous and difficult reaction conditions, including multi-step synthesis have to a certain extent held back the adoption of these complex functional materials in applied research. In a pragmatic approach, a sustainable framework was developed in this thesis to seek out more practical methods, limiting the amount of reaction steps and overtly hazardous chemicals.In a first study, we set out to simplify and scale-up the synthesis of cyclic carbonates with pendant functional groups, capable of undergoing controlled ring-opening polymerization. By avoiding the use of protective-group chemistry we were able two devise a two-step method to create a library of functional monomers. Results in this study show that reactive intermediates could be isolated on 100 g scales, which in a second step was functionalized with a desired alcohol.With this framework in mind, key practical decisions were made to drastically re-think the work up procedures for greater scalability of bis-MPA dendrimers. In this work, a more efficient, scalable and sustainable approach was devised. Elimination of traditional arduous purification steps led to the synthesis of monodisperse dendrimers up to the sixth generation, with 192 functional groups on 50 g scales. Further work included the omission of protective group-chemistry, using orthogonal functional groups to cut the number of synthetic steps by half.The know-how developed in the first two projects led us to pursue greater scalability of functional polycarbonates through a simpler polymerization technique. The method allowed the step-growth polymerization of functional materials from more easily accessible monomers isolated on 100 g scales. Subsequent polymerization afforded materials with glass transition temperatures in the range of -45 °C to 169 °C. The method served as a complement to cyclic carbonates, offering a wider range of functional monomers. Furthermore, by careful choice of assembly method, both alternating and scrambled compositions could be achieved.In a final study, we set out to take advantage of the scrambling mechanism. Control of the final composition of highly rigid degradable polycarbonates was pursued, using renewable building-blocks derived from sugar. In a proof of concept study, thermal and hydrolytic stability of these materials is shown to be dependent on both amount and configuration of each monomer in the final material.
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| 10. |
- Ingverud, Tobias, et al.
(författare)
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Helux : A Heterofunctional Hyperbranched Poly(amido amine) Carboxylate
- 2019
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Ingår i: ACS APPLIED POLYMER MATERIALS. - : AMER CHEMICAL SOC. - 2637-6105. ; 1:7, s. 1845-1853
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Tidskriftsartikel (refereegranskat)abstract
- Herein we present the first scientific report on the commercially available Helux 33/16 - a heterofunctional poly(amido amine carboxylate) hyperbranched polymer (Native Helux). The Native Helux, built from diethyl maleate (DEM) and diaminohexane (HMDA), was characterized, in part aided by reverse engineering of a similar scaffold with the same monomers. Different purification methods resulted in higher molecular weight polymers ranging from 8.4 to 51.7 kDa (M-w), and the Helux considered the purest, having 10 mmol (primary and secondary amines)/g as well as 2-4 mmol carboxylic/g Helux. Additionally, aqueous-mediated postmodifications of Helux were achieved including Michael addition, guanylation, and ring-opening of sultone, as well as water/ethyl acetate-mediated amidation of imidazole-activated pentenoic acid. The inherent heterofunctionality of Helux, amines and carboxylic groups, was further explored by a one-component self-cross-linking approach that yielded a dendritic poly(amido amine) network with autofluorescence-exhibiting properties and a T-g of 59 degrees C. The Helux network exhibited a storage modulus (G') of 7.9 MPa at 25 degrees C and in dry state, and 0.9 MPa (G') when plasticized by 50 wt % swelling (in water) of the network. Finally, dendritic hydrogels based on Helux were produced by a spontaneous NHS-amidation reaction with difunctional 10kPEG-NHS. The mechanical properties of the hydrogels were found to be dependent on the curing temperature for the hydrogel, yielding a G' of 8 and 14.5 kPa, a stress at break of 11.5 and 22.7 kPa, and a strain-at-break of 161 and 163%, at 25 and 37 degrees C, respectively.
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| 11. |
- Kikionis, Stefanos, et al.
(författare)
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Nanofibrous nonwovens based on dendritic-linear-dendritic poly(ethylene glycol) hybrids
- 2018
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Ingår i: Journal of Applied Polymer Science. - : John Wiley & Sons. - 0021-8995 .- 1097-4628. ; 135:10
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Tidskriftsartikel (refereegranskat)abstract
- Dendritic-linear-dendritic (DLD) hybrids are highly functional materials combining the properties of linear and dendritic polymers. Attempts to electrospin DLD polymers composed of hyperbranched dendritic blocks of 2,2-bis(hydroxymethyl) propionic acid on a linear poly(ethylene glycol) core proved unsuccessful. Nevertheless, when these DLD hybrids were blended with an array of different biodegradable polymers as entanglement enhancers, nanofibrous nonwovens were successfully prepared by electrospinning. The pseudogeneration degree of the DLDs, the nature of the co-electrospun polymer and the solvent systems used for the preparation of the electrospinning solutions exerted a significant effect on the diameter and morphology of the electrospun fibers. It is worth-noting that aqueous solutions of the DLD polymers and only 1% (w/v) poly(ethylene oxide) resulted in the production of smoother and thinner nanofibers. Such dendritic nanofibrous scaffolds can be promising materials for biomedical applications due to their bio-compatibility, biodegradability, multifunctionality, and advanced structural architecture.
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| 12. |
- Latorre-Sanchez, Alejandro, et al.
(författare)
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Active quinine-based films able to release antimicrobial compounds via melt quaternization at low temperature
- 2018
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Ingår i: Journal of materials chemistry. B. - : ROYAL SOC CHEMISTRY. - 2050-750X .- 2050-7518. ; 6:1, s. 98-104
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Tidskriftsartikel (refereegranskat)abstract
- The fabrication of antibacterial films based on renewable materials (e.g., chitosan) has attracted significant interest in fields such as food packaging, health care and medicine. However, exploiting the antibacterial properties of cinchona alkaloids to design active nanostructured films able to release quinine-based antimicrobial compounds has not been considered previously. Herein, we develop two different routes to produce active quinine-based nanostructured cross-linked films by exploiting the multiple reactive sites of quinine and, specifically, both the nitrogen atom and the vinyl group of the quinuclidine portion of the molecule, as well as their corresponding orthogonal quaternization and thiol-ene coupling reactions. The first synthetic strategy produces stiff and brittle nanostructured quinine-based films of limited utility for practical applications. Conversely, the second approach produces active, flexible and nanostructured quinine-based films (T-g = - 14 degrees C, Young's modulus = 1.3 GPa), which are able to release antimicrobial compounds against E. coli that, remarkably, are noncytotoxic against mouse macrophage and human dermal fibroblast cells. These kinds of active cinchona alkaloid-based coatings are easy to prepare by means of simple, solvent-free, melt quaternization/spreading procedures at a relatively low temperature (120 degrees C), making this second approach one of the most facile reported procedures to date to produce active nanostructured bio-based films.
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| 13. |
- Martin-Serrano Ortiz, Angela, et al.
(författare)
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Design of multivalent fluorescent dendritic probes for site-specific labeling of biomolecules
- 2018
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Ingår i: Journal of Polymer Science Part A. - : WILEY. - 0887-624X .- 1099-0518. ; 56:15, s. 1609-1616
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Tidskriftsartikel (refereegranskat)abstract
- Herein, the synthesis and characterization of orthogonal dendrons decorated with multiple units of fluorescent and a chemoselective group at a focal point, followed by specific antibody labeling, is presented. Fluorescence results confirm the applicability of the fluorescent probes for biomolecule labeling and fluorescent signal amplification.
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| 14. |
- Nordström, Randi, 1986-, et al.
(författare)
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Degradable dendritic nanogels as carriers for antimicrobial peptides
- 2019
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Ingår i: Journal of Colloid and Interface Science. - : Elsevier BV. - 0021-9797 .- 1095-7103. ; 554, s. 592-602
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Tidskriftsartikel (refereegranskat)abstract
- In the present study, we investigate degradable anionic dendritic nanogels (DNG) as carriers for antimicrobial peptides (AMPs). In such systems, the dendritic part contains carboxylic acid-based anionic binding sites for cationic AMPs, whereas linear poly(ethylene glycol) (PEG) chains form a shell for promotion of biological stealth. In order to clarify factors influencing membrane interactions of such systems, we here address effects of nanogel charge, cross-linking, and degradation on peptide loading/release, as well as consequences of these factors for lipid membrane interactions and antimicrobial effects. The DNGs were found to bind the AMPs LL-37 (LLGDFFRKSKEKIGKEFKRIVQRIKDFLRNLVPRTES) and DPK-060 (GKHKNKGKKNGKHNGWKWWW). For the smaller DPK-060 peptide, loading was found to increase with increasing nanogel charge density. For the larger LL-37, on the other hand, peptide loading was largely insensitive to nanogel charge density. In line with this, results on the secondary structure, as well as on the absence of stabilization from proteolytic degradation by the nanogels, show that the larger LL-37 is unable to enter into the interior of the nanogels. While 40–60% nanogel degradation occurred over 10 days, promoted at high ionic strength and lower cross-linking density/higher anionic charge content, peptide release at physiological ionic strength was substantially faster, and membrane destabilization not relying on nanogel degradation. Ellipsometry and liposome leakage experiments showed both free peptide and peptide/DNG complexes to cause membrane destabilization, indicated also by antimicrobial activities being comparable for nanogel-bound and free peptide. Finally, the DNGs were demonstrated to display low toxicity towards erythrocytes even at peptide concentrations of 100 µM.
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| 15. |
- Nordström, Randi, et al.
(författare)
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Membrane interactions of microgels as carriers of antimicrobial peptides
- 2018
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Ingår i: Journal of Colloid and Interface Science. - : Academic Press Inc.. - 0021-9797 .- 1095-7103. ; 513, s. 141-150
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Tidskriftsartikel (refereegranskat)abstract
- Microgels are interesting as potential delivery systems for antimicrobial peptides. In order to elucidate membrane interactions of such systems, we here investigate effects of microgel charge density on antimicrobial peptide loading and release, as well as consequences of this for membrane interactions and antimicrobial effects, using ellipsometry, circular dichroism spectroscopy, nanoparticle tracking analysis, dynamic light scattering and z-potential measurements. Anionic poly(ethyl acrylate-co-methacrylic acid) microgels were found to incorporate considerable amounts of the cationic antimicrobial peptides LL-37 (LLGDFFRKSKEKIGKEFKRIVQRIKDFLRNLVPRTES) and DPK-060 (GKHKNKGKKNGKHNGWKWWW) and to protect incorporated peptides from degradation by infection-related proteases at high microgel charge density. As a result of their net negative z-potential also at high peptide loading, neither empty nor peptide-loaded microgels adsorb at supported bacteria-mimicking membranes. Instead, membrane disruption is mediated almost exclusively by peptide release. Mirroring this, antimicrobial effects against several clinically relevant bacteria (methicillin-resistant Staphylococcus aureus (MRSA), Escherichia coli, and Pseudomonas aeruginosa) were found to be promoted by factors facilitating peptide release, such as decreasing peptide length and decreasing microgel charge density. Microgels were further demonstrated to display low toxicity towards erythrocytes. Taken together, the results demonstrate some interesting opportunities for the use of microgels as delivery systems for antimicrobial peptides, but also highlight several key factors which need to be controlled for their successful use.
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| 16. |
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| 17. |
- Olsson, Johan V., et al.
(författare)
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Fluoride-promoted carbonylation polymerization : A facile step-growth technique to polycarbonates
- 2017
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Ingår i: Chemical Science. - : Royal Society of Chemistry. - 2041-6520 .- 2041-6539. ; 8:7, s. 4853-4857
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Tidskriftsartikel (refereegranskat)abstract
- Fluoride-Promoted Carbonylation (FPC) polymerization is herein presented as a novel catalytic polymerization methodology that complements ROP and unlocks a greater synthetic window to advanced polycarbonates. The overall two-step strategy is facile, robust and capitalizes on the synthesis and step-growth polymerization of bis-carbonylimidazolide and diol monomers of 1,3- or higher configurations. Cesium fluoride (CsF) is identified as an efficient catalyst and the bis-carbonylimidazolide monomers are synthesized as bench-stable white solids, easily obtained on 50-100 g scales from their parent diols using cheap commercial 1,1′-carbonyldiimidazole (CDI) as activating reagent. The FPC polymerization works well in both solution and bulk, does not require any stoichiometric additives or complex settings and produces only imidazole as a relatively low-toxicity by-product. As a proof-of-concept using only four diol building-blocks, FPC methodology enabled the synthesis of a unique library of polycarbonates covering (i) rigid, flexible and reactive PC backbones, (ii) molecular weights 5-20 kg mol-1, (iii) dispersities of 1.3-2.9 and (iv) a wide span of glass transition temperatures, from -45 up to 169 °C.
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| 18. |
- Rozenbaum, Rene T., et al.
(författare)
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Penetration and Accumulation of Dendrons with Different Peripheral Composition in Pseudomonas aeruginosa Biofilms
- 2019
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Ingår i: Nano letters (Print). - : American Chemical Society (ACS). - 1530-6984 .- 1530-6992. ; 19:7, s. 4327-4333
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Tidskriftsartikel (refereegranskat)abstract
- Multidrug resistant bacterial infections threaten to become the number one cause of death by the year 2050. Development of antimicrobial dendritic polymers is considered promising as an alternative infection control strategy. For antimicrobial dendritic polymers to effectively kill bacteria residing in infectious biofilms, they have to penetrate and accumulate deep into biofilms. Biofilms are often recalcitrant to antimicrobial penetration and accumulation. Therefore, this work aims to determine the role of compact dendrons with different peripheral composition in their penetration into Pseudomonas aeruginosa biofilms. Red fluorescently labeled dendrons with pH-responsive NH3+ peripheral groups initially penetrated faster from a buffer suspension at pH 7.0 into the acidic environment of P. aeruginosa biofilms than dendrons with OH or COO- groups at their periphery. In addition, dendrons with NH3+ peripheral groups accumulated near the top of the biofilm due to electrostatic double-layer attraction with negatively charged biofilm components. However, accumulation of dendrons with OH and COO- peripheral groups was more evenly distributed across the depth of the biofilms than NH3+ composed dendrons and exceeded accumulation of NH3+ composed dendrons after 10 min of exposure. Unlike dendrons with NH3+ groups at their periphery, dendrons with OH or COO- peripheral groups, lacking strong electrostatic double-layer attraction with biofilm components, were largely washed-out during exposure to PBS without dendrons. Thus, penetration and accumulation of dendrons into biofilms is controlled by their peripheral composition through electrostatic double-layer interactions, which is an important finding for the further development of new antimicrobial or antimicrobial-carrying dendritic polymers.
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| 19. |
- Stenström, Patrik, et al.
(författare)
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Evaluation of amino-functional polyester dendrimers based on Bis-MPA as nonviral vectors for siRNA delivery
- 2018
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Ingår i: Molecules. - : MDPI AG. - 1431-5157 .- 1420-3049. ; 23:8
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Tidskriftsartikel (refereegranskat)abstract
- Herein, we present the first evaluation of cationic dendrimers based on 2,2-bis(methylol)propionic acid (bis-MPA) as nonviral vectors for transfection of short interfering RNA (siRNA) in cell cultures. The study encompassed dendrimers of generation one to four (G1-G4), modified to bear 6-48 amino end-groups, where the G2-G4 proved to be capable of siRNA complexation and protection against RNase-mediated degradation. The dendrimers were nontoxic to astrocytes, glioma (C6), and glioblastoma (U87), while G3 and G4 exhibited concentration dependent toxicity towards primary neurons. The G2 showed no toxicity to primary neurons at any of the tested concentrations. Fluorescence microscopy experiments suggested that the dendrimers are highly efficient at endo-lysosomal escape since fluorescently labeled dendrimers were localized specifically in mitochondria, and diffuse cytosolic distribution of fluorescent siRNA complexed by dendrimers was observed. This is a desired feature for intracellular drug delivery, since the endocytic pathway otherwise transfers the drugs into lysosomes where they can be degraded without reaching their intended target. siRNA-transfection was successful in C6 and U87 cell lines using the G3 and G4 dendrimers followed by a decrease of approximately 20% of target protein p42-MAPK expression.
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| 20. |
- Stenström, Patrik, et al.
(författare)
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Synthesis and in Vitro Evaluation of Monodisperse Amino-Functional Polyester Dendrimers with Rapid Degradability and Antibacterial Properties
- 2017
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Ingår i: Biomacromolecules. - : American Chemical Society (ACS). - 1525-7797 .- 1526-4602. ; 18:12, s. 4323-4330
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Tidskriftsartikel (refereegranskat)abstract
- Amine functional polymers, especially cationically charged, are interesting biomacromolecules for several reasons, including easy cell membrane entrance, their ability to escape endosomes through the proton sponge effect, spontaneous complexation and delivery of drugs and siRNA, and simple functionalization in aqueous solutions. Dendrimers, a subclass of precision polymers, are monodisperse and exhibit a large and exact number of peripheral end groups in relation to their size and have shown promise in drug delivery, biomedical imaging and as antiviral agents. In this work, hydroxyl functional dendrimers of generation 1 to 5 based on 2,2-bis(methylol)propionic acid (bis-MPA) were modified to bear 6 to 96 peripheral amino groups through esterification reactions with beta-alanine. All dendrimers were isolated in high yields and with remarkable monodispersity. This was successfully accomplished utilizing the present advantages of fluoride-promoted esterification (FPE) with imidazole-activated monomers. Straightforward postfunctionalization was conducted on a second generation amino functional dendrimer with tetraethylene glycol through NHS-amidation and carbonyl diimidazole (CDI) activation to full conversion with short reaction times. Fast biodegradation of the dendrimers through loss of peripheral beta-alanine groups was observed and generational- and dose-dependent cytotoxicity was evaluated with a set of cell lines. An increase. in neurotoxicity compared to hydroxyl-functional dendrimers was shown in neuronal cells, however, the dendrimers were slightly less neurotoxic than commercially available poly(amidoamine) dendrimers (PAMAMs). Additionally, their effect on bacteria was evaluated and the second generation dendrimer was found unique inhibiting the growth of Escherichia coli at physiological conditions while being nontoxic toward human cells. Finally, these results cement a robust and sustainable synthetic route to amino-functional polyester dendrimers with interesting chemical and biological properties.
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| 21. |
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| 22. |
- Zhang, Yuning, et al.
(författare)
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Off-Stoichiometric Thiol-Ene Chemistry to Dendritic Nanogel Therapeutics
- 2019
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Ingår i: Advanced Functional Materials. - : Wiley-VCH Verlag. - 1616-301X .- 1616-3028. ; 29:18
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Tidskriftsartikel (refereegranskat)abstract
- A novel platform of dendritic nanogels is herein presented, capitalizing on the self-assembly of allyl-functional polyesters based on dendritic-linear-dendritic amphiphiles followed by simple cross-linking with complementary monomeric thiols via UV initiated off-stoichiometric thiol-ene chemistry. The facile approach enabled multigram creation of allyl reactive nanogel precursors, in the size range of 190–295 nm, being readily available for further modifications to display a number of core functionalities while maintaining the size distribution and characteristics of the master batch. The nanogels are evaluated as carriers of a spread of chemotherapeutics by customizing the core to accommodate each individual cargo. The resulting nanogels are biocompatible, displaying diffusion controlled release of cargo, maintained therapeutic efficacy, and decreased cargo toxic side effects. Finally, the nanogels are found to successfully deliver pharmaceuticals into a 3D pancreatic spheroids tumor model.
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