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Ingverud, T., Erlandsson, J., Wågberg, L. & Malkoch, M. (2020). Dendritic Polyampholyte-Assisted Formation of Functional Cellulose Nanofibril Materials. Biomacromolecules, 21(7), 2856-2863
Öppna denna publikation i ny flik eller fönster >>Dendritic Polyampholyte-Assisted Formation of Functional Cellulose Nanofibril Materials
2020 (Engelska)Ingår i: Biomacromolecules, ISSN 1525-7797, E-ISSN 1526-4602, Vol. 21, nr 7, s. 2856-2863Artikel i tidskrift (Refereegranskat) Published
Abstract [en]

A new platform of functional hybrid materials from anionically charged high-aspect-ratio cellulose nanofibrils (CNFs) and a dendritic polyampholyte, Helux, is herein proposed. The polyampholytic character of Helux enabled facile and efficient nanoscale mixing with the CNFs, and the resulting composite mixtures of CNFs and Helux displayed thixotropic behavior and formed physical and reversibly cross-linked gels when left unperturbed for short spans of time. The gel could be chemically cross-linked into self-supporting solid hydrogels containing impressive water contents of 99.6% and a storage modulus of 1.8 kPa by thermal activation. Non-cross-linked mixtures of CNF/Helux were assembled into composites, such as films by solvent casting and aerogels with densities as low as 4 kg/m(3) by lyophilizing ice-templated CNF/Helux mixtures. The resulting materials exhibited excellent wet stability due to the heat-activated cross-linking and were readily available for postfunctionalization via amidation chemistry using Helux-accessible amines in aqueous conditions. The mechanical performance of the films was not jeopardized by the addition of Helux. Additionally, by varying the amount of Helux, the compressive elastic modulus of aerogels was tunable in both the non-cross-linked and cross-linked states. The fast and efficient nanoscale mixing of anionic CNFs and a polymer containing cationic groups is unique, novel, and promising as a functional material platform. Sustainable CNFs guided by heterofunctional dendritic polyampholytes are envisaged to act as a pillar toward high-performance applications, including biomedicine and biomaterials.

Ort, förlag, år, upplaga, sidor
American Chemical Society (ACS), 2020
Nationell ämneskategori
Materialteknik
Identifikatorer
urn:nbn:se:kth:diva-288612 (URN)10.1021/acs.biomac.0c00573 (DOI)000599012600027 ()32501668 (PubMedID)2-s2.0-85088200667 (Scopus ID)
Anmärkning

QC 20210112

Tillgänglig från: 2021-01-12 Skapad: 2021-01-12 Senast uppdaterad: 2022-06-25Bibliografiskt granskad
Andrén, O. C. J., Ingverud, T., Hult, D., Håkansson, J., Bogestål, Y., Caous, J. S., . . . Malkoch, M. (2019). Antibiotic-Free Cationic Dendritic Hydrogels as Surgical-Site-Infection-Inhibiting Coatings. Advanced Healthcare Materials, 8(5)
Öppna denna publikation i ny flik eller fönster >>Antibiotic-Free Cationic Dendritic Hydrogels as Surgical-Site-Infection-Inhibiting Coatings
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2019 (Engelska)Ingår i: Advanced Healthcare Materials, ISSN 2192-2640, E-ISSN 2192-2659, Vol. 8, nr 5Artikel i tidskrift (Refereegranskat) Published
Abstract [en]

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 ?-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.

Ort, förlag, år, upplaga, sidor
John Wiley & Sons, Ltd, 2019
Nyckelord
antibacterial, dendrimer, hydrogels, surgical-site infection
Nationell ämneskategori
Polymerkemi
Identifikatorer
urn:nbn:se:kth:diva-249169 (URN)10.1002/adhm.201801619 (DOI)000461575200014 ()30735288 (PubMedID)2-s2.0-85061270456 (Scopus ID)
Anmärkning

QC 20190412

Tillgänglig från: 2019-04-11 Skapad: 2019-04-11 Senast uppdaterad: 2022-12-08Bibliografiskt granskad
Ingverud, T. & Malkoch, M. (2019). Helux: A Heterofunctional Hyperbranched Poly(amido amine) Carboxylate. ACS APPLIED POLYMER MATERIALS, 1(7), 1845-1853
Öppna denna publikation i ny flik eller fönster >>Helux: A Heterofunctional Hyperbranched Poly(amido amine) Carboxylate
2019 (Engelska)Ingår i: ACS APPLIED POLYMER MATERIALS, ISSN 2637-6105, Vol. 1, nr 7, s. 1845-1853Artikel i tidskrift (Refereegranskat) Published
Abstract [en]

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.

Ort, förlag, år, upplaga, sidor
AMER CHEMICAL SOC, 2019
Nyckelord
commercial, heterofunctional, hyperbranched, polyampholyte, postfunctionalization, self-cross-linking, hydrogel
Nationell ämneskategori
Polymerkemi
Identifikatorer
urn:nbn:se:kth:diva-256273 (URN)10.1021/acsapm.9b00364 (DOI)000476967100025 ()2-s2.0-85087565618 (Scopus ID)
Anmärkning

QC 20191029

Tillgänglig från: 2019-10-29 Skapad: 2019-10-29 Senast uppdaterad: 2022-06-26Bibliografiskt granskad
Hult, D., Garcia-Gallego, S., Ingverud, T., Andrén, O. & Malkoch, M. (2018). Degradable High Tg Sugar Derived Polycarbonates from Isosorbide and Dihydroxyacetone. Polymer Chemistry, 9(17), 2238-2246
Öppna denna publikation i ny flik eller fönster >>Degradable High Tg Sugar Derived Polycarbonates from Isosorbide and Dihydroxyacetone
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2018 (Engelska)Ingår i: Polymer Chemistry, ISSN 1759-9954, E-ISSN 1759-9962, Vol. 9, nr 17, s. 2238-2246Artikel i tidskrift (Refereegranskat) Published
Abstract [en]

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.

Ort, förlag, år, upplaga, sidor
Royal Society of Chemistry, 2018
Nationell ämneskategori
Polymerkemi
Identifikatorer
urn:nbn:se:kth:diva-224753 (URN)10.1039/C8PY00256H (DOI)000431183700004 ()2-s2.0-85046299922 (Scopus ID)
Forskningsfinansiär
Vetenskapsrådet, 2011-5358 2010-435 2015-04779Knut och Alice Wallenbergs Stiftelse, 2012-0196
Anmärkning

QC 20180322

Tillgänglig från: 2018-03-22 Skapad: 2018-03-22 Senast uppdaterad: 2024-03-18Bibliografiskt granskad
Erlandsson, J., Pettersson, T., Ingverud, T., Granberg, H., Larsson, P. A., Malkoch, M. & Wågberg, L. (2018). On the mechanism behind freezing-induced chemical crosslinking in ice-templated cellulose nanofibril aerogels. Journal of Materials Chemistry A, 6(40), 19371-19380
Öppna denna publikation i ny flik eller fönster >>On the mechanism behind freezing-induced chemical crosslinking in ice-templated cellulose nanofibril aerogels
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2018 (Engelska)Ingår i: Journal of Materials Chemistry A, ISSN 2050-7488, Vol. 6, nr 40, s. 19371-19380Artikel i tidskrift (Refereegranskat) Published
Abstract [en]

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.

Ort, förlag, år, upplaga, sidor
Royal Society of Chemistry, 2018
Nyckelord
Aerogels, Aldehydes, Cellulose, Chemical stability, Crosslinking, Freezing, Nanofibers, Acidic conditions, Ambient conditions, Cellulose nanofibrils (CNFs), Chemical cross-linking, Freezing process, Lower critical, Periodate oxidation, Solvent exchanges, Ice
Nationell ämneskategori
Polymerteknologi
Identifikatorer
urn:nbn:se:kth:diva-247488 (URN)10.1039/c8ta06319b (DOI)000448413100008 ()2-s2.0-85055128762 (Scopus ID)
Anmärkning

QC 20190405

Tillgänglig från: 2019-04-05 Skapad: 2019-04-05 Senast uppdaterad: 2022-06-26Bibliografiskt granskad
Kamada, A., Mittal, N., Söderberg, L. D., Ingverud, T., Ohm, W., Roth, S. V., . . . Lendel, C. (2017). Flow-assisted assembly of nanostructured protein microfibers. Proceedings of the National Academy of Sciences of the United States of America, 114(6), 1232-1237
Öppna denna publikation i ny flik eller fönster >>Flow-assisted assembly of nanostructured protein microfibers
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2017 (Engelska)Ingår i: Proceedings of the National Academy of Sciences of the United States of America, ISSN 0027-8424, E-ISSN 1091-6490, Vol. 114, nr 6, s. 1232-1237Artikel i tidskrift (Refereegranskat) Published
Abstract [en]

Some of the most remarkable materials in nature are made from proteins. The properties of these materials are closely connected to the hierarchical assembly of the protein building blocks. In this perspective, amyloid-like protein nanofibrils (PNFs) have emerged as a promising foundation for the synthesis of novel bio-based materials for a variety of applications. Whereas recent advances have revealed the molecular structure of PNFs, the mechanisms associated with fibril-fibril interactions and their assembly into macroscale structures remain largely unexplored. Here, we show that whey PNFs can be assembled into microfibers using a flow-focusing approach and without the addition of plasticizers or cross-linkers. Microfocus small-angle X-ray scattering allows us to monitor the fibril orientation in the microchannel and compare the assembly processes of PNFs of distinct morphologies. We find that the strongest fiber is obtained with a sufficient balance between ordered nanostructure and fibril entanglement. The results provide insights in the behavior of protein nanostructures under laminar flow conditions and their assembly mechanism into hierarchical macroscopic structures.

Ort, förlag, år, upplaga, sidor
PNAS, 2017
Nyckelord
protein nanofibrils, amyloid, hierarchical assembly, flow focusing, small-angle X-ray scattering
Nationell ämneskategori
Kemi
Identifikatorer
urn:nbn:se:kth:diva-203155 (URN)10.1073/pnas.1617260114 (DOI)000393422200026 ()28123065 (PubMedID)2-s2.0-85011654002 (Scopus ID)
Anmärkning

Qc 20170315

Tillgänglig från: 2017-03-15 Skapad: 2017-03-15 Senast uppdaterad: 2024-03-15Bibliografiskt granskad
Ingverud, T., Larsson, E., Hemmer, G., Rojas, R., Malkoch, M. & Carlmark, A. (2016). High water-content thermoresponsive hydrogels via electrostatic macrocrosslinking of cellulose nanofibrils. Journal of Polymer Science Part A: Polymer Chemistry, 54(21), 3415-3424
Öppna denna publikation i ny flik eller fönster >>High water-content thermoresponsive hydrogels via electrostatic macrocrosslinking of cellulose nanofibrils
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2016 (Engelska)Ingår i: Journal of Polymer Science Part A: Polymer Chemistry, ISSN 0887-624X, E-ISSN 1099-0518, Vol. 54, nr 21, s. 3415-3424Artikel i tidskrift (Refereegranskat) Published
Abstract [en]

Atom transfer radical polymerization (ATRP) has been utilized to synthesize tri- and star-block copolymers of poly(di(ethylene glycol)methyl ether methacrylate) (PDEGMA) and quaternized poly(2-(dimethylamino)ethyl methacrylate) (qPDMAEMA). The block copolymers, all with a minimum of two cationically charged blocks, were sequentially used for electrostatic macrocrosslinking of a dilute dispersion of anionic TEMPO-oxidized cellulose nanofibrils (CNF, 0.3 wt%), forming free-standing hydrogels. The cationic block copolymers adsorbed irreversibly to the CNF, enabling the formation of ionically crosslinked hydrogels, with a storage modulus of up to 2.9 kPa. The ability of the block copolymers to adsorb to CNF was confirmed by quartz crystal microbalance with dissipation monitoring (QCM-D) and infrared spectroscopy (FT-IR), and the thermoresponsive properties of the hydrogels were investigated by rheological stress and frequency sweep, and gravimetric measurements. This method was shown to be promising for the facile production of thermoresponsive hydrogels based on CNF.

Ort, förlag, år, upplaga, sidor
John Wiley & Sons, 2016
Nyckelord
ATRP, cationic block copolymer, cellulose nanofibrils, hydrogels, thermoresponsive, Atom transfer radical polymerization, Block copolymers, Cellulose, Electrostatics, Ethylene, Ethylene glycol, Free radical reactions, Infrared spectroscopy, Nanofibers, Quartz crystal microbalances, 2-(dimethylamino)ethyl methacrylate, Cross-linked hydrogels, Gravimetric measurements, Quartz crystal microbalance with dissipation monitoring, Star block copolymer, Thermo-responsive, Thermo-responsive hydrogels
Nationell ämneskategori
Polymerkemi
Identifikatorer
urn:nbn:se:kth:diva-195220 (URN)10.1002/pola.28225 (DOI)000386657600003 ()2-s2.0-84988040360 (Scopus ID)
Anmärkning

QC 20161117

Tillgänglig från: 2016-11-17 Skapad: 2016-11-02 Senast uppdaterad: 2024-03-18Bibliografiskt granskad
Carlsson, L., Ingverud, T., Blomberg, H., Carlmark, A., Larsson, P. T. & Malmström, E. (2015). Surface characteristics of cellulose nanoparticles grafted by surface-initiated ring-opening polymerization of epsilon-caprolactone. Cellulose, 22(2), 1063-1074
Öppna denna publikation i ny flik eller fönster >>Surface characteristics of cellulose nanoparticles grafted by surface-initiated ring-opening polymerization of epsilon-caprolactone
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2015 (Engelska)Ingår i: Cellulose, ISSN 0969-0239, E-ISSN 1572-882X, Vol. 22, nr 2, s. 1063-1074Artikel i tidskrift (Refereegranskat) Published
Abstract [en]

In this study, surface-initiated ring-opening polymerization has been employed for the grafting of epsilon-caprolactone from cellulose nanoparticles, made by partial hydrolysis of cellulose cotton linters. A sacrificial initiator was employed during the grafting reactions, to form free polymer in parallel to the grafting reaction. The degree of polymerization of the polymer grafts, and of the free polymer, was varied by varying the reaction time. The aim of this study was to estimate the cellulose nanoparticle degree of surface substitution at different reaction times. This was accomplished by combining measurement results from spectroscopy and chromatography. The prepared cellulose nanoparticles were shown to have 3.1 (+/- 0.3) % of the total anhydroglucose unit content present at the cellulose nanoparticle surfaces. This effectively limits the amount of cellulose that can be targeted by the SI-ROP reactions. For a certain SI-ROP reaction time, it was assumed that the resulting degree of polymerization (DP) of the grafts and the DP of the free polymer were equal. Based on this assumption it was shown that the cellulose nanoparticle surface degree of substitution remained approximately constant (3-7 %) and seemingly independent of SI-ROP reaction time. We believe this work to be an important step towards a deeper understanding of the processes and properties controlling SI-ROP reactions occurring at cellulose surfaces.

Nyckelord
Solid-state cross-polarization magic angle spinning carbon-13 nuclear magnetic resonance (CP/MAS C-13-NMR), Surface grafting, Ring-opening polymerization, Degree of substitution, Cotton linters, Cellulose
Nationell ämneskategori
Polymerkemi
Identifikatorer
urn:nbn:se:kth:diva-163946 (URN)10.1007/s10570-014-0510-1 (DOI)000350876300010 ()2-s2.0-84925536313 (Scopus ID)
Forskningsfinansiär
VetenskapsrådetForskningsrådet Formas
Anmärkning

QC 20150507

Tillgänglig från: 2015-05-07 Skapad: 2015-04-13 Senast uppdaterad: 2024-03-18Bibliografiskt granskad
Organisationer
Identifikatorer
ORCID-id: ORCID iD iconorcid.org/0000-0002-9486-5288

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