Change search
Refine search result
123 1 - 50 of 117
CiteExportLink to result list
Permanent link
Cite
Citation style
  • apa
  • harvard1
  • ieee
  • modern-language-association-8th-edition
  • vancouver
  • Other style
More styles
Language
  • de-DE
  • en-GB
  • en-US
  • fi-FI
  • nn-NO
  • nn-NB
  • sv-SE
  • Other locale
More languages
Output format
  • html
  • text
  • asciidoc
  • rtf
Rows per page
  • 5
  • 10
  • 20
  • 50
  • 100
  • 250
Sort
  • Standard (Relevance)
  • Author A-Ö
  • Author Ö-A
  • Title A-Ö
  • Title Ö-A
  • Publication type A-Ö
  • Publication type Ö-A
  • Issued (Oldest first)
  • Issued (Newest first)
  • Created (Oldest first)
  • Created (Newest first)
  • Last updated (Oldest first)
  • Last updated (Newest first)
  • Disputation date (earliest first)
  • Disputation date (latest first)
  • Standard (Relevance)
  • Author A-Ö
  • Author Ö-A
  • Title A-Ö
  • Title Ö-A
  • Publication type A-Ö
  • Publication type Ö-A
  • Issued (Oldest first)
  • Issued (Newest first)
  • Created (Oldest first)
  • Created (Newest first)
  • Last updated (Oldest first)
  • Last updated (Newest first)
  • Disputation date (earliest first)
  • Disputation date (latest first)
Select
The maximal number of hits you can export is 250. When you want to export more records please use the Create feeds function.
  • 1.
    Albertsson, Ann-Christine
    et al.
    KTH, School of Chemical Science and Engineering (CHE), Fibre and Polymer Technology, Polymer Technology.
    Edlund, Ulrica
    KTH, School of Chemical Science and Engineering (CHE), Fibre and Polymer Technology, Polymer Technology.
    Barrier layers for packaging laminates and packaging laminates comprising such barrier layers2009Patent (Other (popular science, discussion, etc.))
  • 2.
    Albertsson, Ann-Christine
    et al.
    KTH, School of Chemical Science and Engineering (CHE), Fibre and Polymer Technology, Polymer Technology.
    Edlund, Ulrica
    KTH, School of Chemical Science and Engineering (CHE), Fibre and Polymer Technology, Polymer Technology.
    Efficient conversion of wood hydrolysates into renewable materials2012In: Abstract of Papers of the American Chemical Society, ISSN 0065-7727, Vol. 244Article in journal (Other academic)
  • 3.
    Albertsson, Ann-Christine
    et al.
    KTH, School of Chemical Science and Engineering (CHE), Fibre and Polymer Technology, Polymer Technology.
    Edlund, Ulrica
    KTH, School of Chemical Science and Engineering (CHE), Fibre and Polymer Technology, Polymer Technology.
    New matrices for controlled drug delivery.2000In: ABSTRACTS OF PAPERS OF THE AMERICAN CHEMICAL SOCIETY, American Chemical Society (ACS), 2000Conference paper (Refereed)
  • 4.
    Albertsson, Ann-Christine
    et al.
    KTH, School of Chemical Science and Engineering (CHE), Fibre and Polymer Technology, Polymer Technology.
    Edlund, Ulrica
    KTH, School of Chemical Science and Engineering (CHE), Fibre and Polymer Technology, Polymer Technology.
    Novel release systems from biodegradable polymers1998In: ABSTRACTS OF PAPERS OF THE AMERICAN CHEMICAL SOCIETY, American Chemical Society (ACS), 1998Conference paper (Refereed)
  • 5.
    Albertsson, Ann-Christine
    et al.
    KTH, School of Chemical Science and Engineering (CHE), Fibre and Polymer Technology, Polymer Technology.
    Edlund, Ulrica
    KTH, School of Chemical Science and Engineering (CHE), Fibre and Polymer Technology, Polymer Technology.
    Vedrester blir förnybar råvara2009In: Miljöforskning, ISSN 1650-4925, no 5, p. 20-21Article in journal (Other (popular science, discussion, etc.))
    Abstract [sv]

    Cellulosa används sedan länge i många produkter. Än så länge gäller det främst inom trävaru-, pappers- och massaindustrin. Men veden innehåller även andra ämnen, som idag mest ses som onödiga restprodukter. Aktuell forskning vid KTH visar att sådana produkter i framtiden kan bli användbara i till exempel förpackningar, läkemedelsindustri och jordbruk.

  • 6.
    Albertsson, Ann-Christine
    et al.
    KTH, School of Chemical Science and Engineering (CHE), Fibre and Polymer Technology.
    Edlund, Ulrica
    KTH, School of Chemical Science and Engineering (CHE), Fibre and Polymer Technology.
    Wood hydrolysates: From fractions to products2015In: Abstracts of Papers of the American Chemical Society, ISSN 0065-7727, Vol. 249Article in journal (Other academic)
  • 7.
    Albertsson, Ann-Christine
    et al.
    KTH, School of Chemical Science and Engineering (CHE), Fibre and Polymer Technology, Polymer Technology.
    Edlund, Ulrica
    KTH, School of Chemical Science and Engineering (CHE), Fibre and Polymer Technology, Polymer Technology.
    Wood hydrolysates turned valuable2012In: Abstract of Papers of the American Chemical Society, ISSN 0065-7727, Vol. 243Article in journal (Other academic)
  • 8.
    Albertsson, Ann-Christine
    et al.
    KTH, School of Chemical Science and Engineering (CHE), Fibre and Polymer Technology, Polymer Technology.
    Edlund, Ulrica
    KTH, School of Chemical Science and Engineering (CHE), Fibre and Polymer Technology, Polymer Technology.
    Källrot, Martina
    KTH, School of Chemical Science and Engineering (CHE), Fibre and Polymer Technology, Polymer Technology.
    Surface modification of degradable polymers2005In: ABSTRACTS OF PAPERS OF THE AMERICAN CHEMICAL SOCIETY, American Chemical Society (ACS), 2005Conference paper (Refereed)
  • 9.
    Albertsson, Ann-Christine
    et al.
    KTH, Superseded Departments, Polymer Technology.
    Edlund, Ulrica
    KTH, Superseded Departments, Polymer Technology.
    Stridsberg, K.
    Controlled ring-opening polymerization of lactones and lactides2000In: Macromolecular Symposia, ISSN 1022-1360, E-ISSN 1521-3900, Vol. 157, p. 39-46Article in journal (Refereed)
    Abstract [en]

    1,5-dioxepan-2-one (DXO) is presented as a versatile component in biodegradable polymers for biomedical applications. Copolymerization of DXO and L-lactide yielded a semi-crystalline, yet flexible, material where the extent of crystallinity and erosion characteristics were controlled by an appropriate choice of copolymer composition. Crosslinked PDXO was polymerized as a novel biodegradable elastomer. The degradation behavior of these materials were explored in vitro. Microspheres from poly(DXO-co-L-LA) were prepared and shown to be promising candidates for controlled release. The polymer composition and drug solubility provided effective means of controlling the drug delivery pattern.

  • 10.
    Albertsson, Ann-Christine
    et al.
    KTH, School of Chemical Science and Engineering (CHE), Fibre and Polymer Technology, Polymer Technology.
    Edlund, Ulrica
    KTH, School of Chemical Science and Engineering (CHE), Fibre and Polymer Technology, Polymer Technology.
    Varma, Indra Kumari
    Centre for Polymer Science and Engineering, Indian Institute of Technology, Dehli, India.
    Synthesis, Chemistry and Properties of Hemicelluloses2011In: Biopolymers: New Materials for Sustainable Films and Coatings / [ed] David Plackett, Chichester: John Wiley & Sons, 2011, 1, p. 135-150Chapter in book (Other academic)
  • 11.
    Albertsson, Ann-Christine
    et al.
    KTH, School of Chemical Science and Engineering (CHE), Fibre and Polymer Technology, Polymer Technology.
    Finne-Wistrand, Anna
    KTH, School of Chemical Science and Engineering (CHE), Fibre and Polymer Technology, Polymer Technology.
    Edlund, Ulrica
    KTH, School of Chemical Science and Engineering (CHE), Fibre and Polymer Technology, Polymer Technology.
    Degradable polymers with tailored properties for biomedical materials2009In: Abstract of Papers of the American Chemical Society, ISSN 0065-7727, Vol. 238Article in journal (Other academic)
  • 12.
    Albertsson, Ann-Christine
    et al.
    KTH, School of Chemical Science and Engineering (CHE).
    Kallrot, Martina
    KTH, School of Chemical Science and Engineering (CHE).
    Edlund, Ulrica
    KTH, School of Chemical Science and Engineering (CHE).
    PMSE 295-Silane functionalization of MWNTs improves the mechanical properties of MWNT/epoxy nanocomposites2006In: Abstract of Papers of the American Chemical Society, ISSN 0065-7727, Vol. 232, p. 203-203Article in journal (Other academic)
  • 13.
    Albertsson, Ann-Christine
    et al.
    KTH, School of Chemical Science and Engineering (CHE), Fibre and Polymer Technology, Polymer Technology.
    Källrot, Martina
    KTH, School of Chemical Science and Engineering (CHE), Fibre and Polymer Technology, Polymer Technology.
    Edlund, Ulrica
    KTH, School of Chemical Science and Engineering (CHE), Fibre and Polymer Technology, Polymer Technology.
    POLY 585-Covalent surface modification of degradable polymers2007In: Abstract of Papers of the American Chemical Society, ISSN 0065-7727, Vol. 234Article in journal (Other academic)
  • 14.
    Albertsson, Ann-Christine
    et al.
    KTH, Superseded Departments, Polymer Technology.
    Olander, Björn
    KTH, Superseded Departments, Polymer Technology.
    Edlund, Ulrica
    KTH, Superseded Departments, Polymer Technology.
    Källrot, Martina
    KTH, Superseded Departments, Polymer Technology.
    Increased biocompatibility by surface modification2004In: Abstract of Papers of the American Chemical Society, ISSN 0065-7727, Vol. 228, p. U508-U508Article in journal (Other (popular science, discussion, etc.))
  • 15.
    Albertsson, Ann-Christine
    et al.
    KTH, School of Chemical Science and Engineering (CHE), Fibre and Polymer Technology.
    Voepel, Jens
    KTH, School of Chemical Science and Engineering (CHE), Fibre and Polymer Technology.
    Edlund, Ulrica
    KTH, School of Chemical Science and Engineering (CHE), Fibre and Polymer Technology.
    Dahlman, Olof
    Soderqvist-Lindblad, Margaretha
    Design of Renewable Hydrogel Release Systems from Fiberboard Mill Wastewater2010In: Biomacromolecules, ISSN 1525-7797, E-ISSN 1526-4602, Vol. 11, no 5, p. 1406-1411Article in journal (Refereed)
    Abstract [en]

    A new route for the design of renewable hydrogels is presented. The soluble waste from masonite production was isolated, fractionized, and upgraded. The resulting hemicellulose rich fraction was alkenyl-functionalized and used in the preparation of covalently cross-linked hydrogels capable of sustained release of incorporated agents. Said hydrogels showed a Fickian diffusion-based release of incorporated bovine serum albumin. Also, a method for the coating of seeds with hydrogel was developed. The sustained release of incorporated growth retardant agents from the hydrogel coating on rape seeds was shown to enable the temporary inhibition of germination.

  • 16. Brunius, C. F.
    et al.
    Edlund, Ulrica
    KTH, Superseded Departments, Polymer Technology.
    Albertsson, Ann-Christine
    KTH, Superseded Departments, Polymer Technology.
    Synthesis and in vitro degradation of poly(N-vinyl-2-pyrrolidone)-based graft copolymers for biomedical applications2002In: Journal of Polymer Science Part A: Polymer Chemistry, ISSN 0887-624X, E-ISSN 1099-0518, Vol. 40, no 21, p. 3652-3661Article in journal (Refereed)
    Abstract [en]

    This work is devoted to the design of a novel family of hydrosoluble biomaterials: poly(N-vinyl-2-pyrrolidone) (PVP)-based graft copolymers. A synthesis route has been elaborated in which omega-functionalized PVP is prepared via chain-transfer radical polymerization, end-group modified, and subsequently grafted onto a polyhydroxylated backbone, typically dextran or poly(vinyl alcohol). The resulting graft copolymer biomaterials are designed for use in various biomedical applications, particularly as materials with a stronger potential for plasma expansion than already existing products have. The graft copolymers are potentially degradable because the PVP grafts are connected to the polyol backbone via a hydrolytically labile carbonate or ester linkage. The degradation of the graft copolymers was performed in vitro over a period of 6 weeks.

  • 17.
    Choong, Ferdinand X.
    et al.
    Karolinska Inst, Dept Neurosci, Swedish Med Nanosci Ctr, SE-17177 Stockholm, Sweden..
    Back, Marcus
    Linkoping Univ, IFM, Dept Chem, SE-58183 Linkoping, Sweden..
    Schulz, Anette
    Karolinska Inst, Dept Neurosci, Swedish Med Nanosci Ctr, SE-17177 Stockholm, Sweden..
    Nilsson, K. Peter. R.
    Linkoping Univ, IFM, Dept Chem, SE-58183 Linkoping, Sweden..
    Edlund, Ulrica
    KTH, School of Chemical Science and Engineering (CHE), Fibre and Polymer Technology.
    Richter-Dahlfors, Agneta
    Karolinska Inst, Dept Neurosci, Swedish Med Nanosci Ctr, SE-17177 Stockholm, Sweden..
    Stereochemical identification of glucans by oligothiophenes enables cellulose anatomical mapping in plant tissues2018In: Scientific Reports, ISSN 2045-2322, E-ISSN 2045-2322, Vol. 8, article id 3108Article in journal (Refereed)
    Abstract [en]

    Efficient use of plant-derived materials requires enabling technologies for non-disruptive composition analysis. The ability to identify and spatially locate polysaccharides in native plant tissues is difficult but essential. Here, we develop an optical method for cellulose identification using the structure-responsive, heptameric oligothiophene h-FTAA as molecular fluorophore. Spectrophotometric analysis of h-FTAA interacting with closely related glucans revealed an exceptional specificity for beta-linked glucans. This optical, non-disruptive method for stereochemical differentiation of glycosidic linkages was next used for in situ composition analysis in plants. Multi-laser/multi-detector analysis developed herein revealed spatial localization of cellulose and structural cell wall features such as plasmodesmata and perforated sieve plates of the phloem. Simultaneous imaging of intrinsically fluorescent components revealed the spatial relationship between cell walls and other organelles, such as chloroplasts and lignified annular thickenings of the trachea, with precision at the sub-cellular scale. Our non-destructive method for cellulose identification lays the foundation for the emergence of anatomical maps of the chemical constituents in plant tissues. This rapid and versatile method will likely benefit the plant science research fields and may serve the biorefinery industry as reporter for feedstock optimization as well as in-line monitoring of cellulose reactions during standard operations.

  • 18. Choong, Ferdinand X.
    et al.
    Back, Marcus
    Steiner, Svava E.
    Melican, Keira
    Nilsson, K. Peter R.
    Edlund, Ulrica
    KTH, School of Chemical Science and Engineering (CHE), Fibre and Polymer Technology.
    Richter-Dahlfors, Agneta
    Nondestructive, real-time determination and visualization of cellulose, hemicellulose and lignin by luminescent oligothiophenes2016In: Scientific Reports, ISSN 2045-2322, E-ISSN 2045-2322, Vol. 6, article id 35578Article in journal (Refereed)
    Abstract [en]

    Enabling technologies for efficient use of the bio-based feedstock are crucial to the replacement of oil-based products. We investigated the feasibility of luminescent conjugated oligothiophenes (LCOs) for non-destructive, rapid detection and quality assessment of lignocellulosic components in complex biomass matrices. A cationic pentameric oligothiophene denoted p-HTEA (pentamer hydrogen thiophene ethyl amine) showed unique binding affinities to cellulose, lignin, hemicelluloses, and cellulose nanofibrils in crystal, liquid and paper form. We exploited this finding using spectrofluorometric methods and fluorescence confocal laser scanning microscopy, for sensitive, simultaneous determination of the structural and compositional complexities of native lignocellulosic biomass. With exceptional photostability, p-HTEA is also demonstrated as a dynamic sensor for real-time monitoring of enzymatic cellulose degradation in cellulolysis. These results demonstrate the use of p-HTEA as a non-destructive tool for the determination of cellulose, hemicellulose and lignin in complex biomass matrices, thereby aiding in the optimization of biomass-converting technologies.

  • 19.
    Choong, Ferdinand X.
    et al.
    Swedish Medical Nanoscience Center, Department of Neuroscience Karolinska Institutet, Stockholm, Sweden.
    Lantz, Linda
    Department of Chemistry IFM, Linköping University, Linköping, Sweden.
    Shirani, Hamid
    Department of Chemistry IFM, Linköping University, Linköping, Sweden.
    Schulz, Anette
    Swedish Medical Nanoscience Center, Department of Neuroscience, Karolinska Institutet, Stockholm, Sweden.
    Nilsson, K. Peter R.
    Department of Chemistry IFM, Linköping University, Linköping, Sweden.
    Edlund, Ulrica
    KTH, School of Engineering Sciences in Chemistry, Biotechnology and Health (CBH), Fibre- and Polymer Technology, Polymer Technology.
    Richter-Dahlfors, Agneta
    Swedish Medical Nanoscience Center, Department of Neuroscience, Karolinska Institutet, Stockholm, Sweden.
    Stereochemical Identification of Glucans by a Donor-Acceptor-Donor Conjugated Pentamer Enables Multi-Carbohydrate Anatomical Mapping in Plant Tissues2019In: Cellulose (London), ISSN 0969-0239, E-ISSN 1572-882X, Vol. 26, no 7, p. 4253-4264Article in journal (Refereed)
    Abstract [en]

    Optotracing is a novel method for analytical imaging of carbohydrates in plant and microbial tissues. This optical method applies structure-responsive oligothiophenes as molecular fluorophores emitting unique optical signatures when bound to polysaccharides. Herein, we apply Carbotrace680, a short length anionic oligothiophene with a central heterocyclic benzodithiazole (BTD) motif, to probe for different glucans. The donor-acceptor-donor type electronic structure of Carbotrace680 provides improved spectral properties compared to oligothiophenes due to the possibility of intramolecular charge-transfer transition to the BTD motif. This enables differentiation of glucans based on the glycosidic linkage stereochemistry. Thus -configured starch is readily differentiated from -configured cellulose. The versatility of optotracing is demonstrated by dynamic monitoring of thermo-induced starch remodelling, shown in parallel by spectrophotometry and microscopy of starch granules. Imaging of Carbotrace680 bound to multiple glucans in plant tissues provided direct identification of their physical locations, revealing the spatial relationship between structural (cellulose) and storage (starch) glucans at sub-cellular scale. Our work forms the basis for the development of superior optotracers for sensitive detection of polysaccharides. Our non-destructive method for anatomical mapping of glucans in biomass will serve as an enabling technology for developments towards efficient use of plant-derived materials and biomass.

  • 20.
    Dahlman, Olof
    et al.
    Innventia AB.
    Söderqvist Lindblad, Margaretha
    Södra Cell AB.
    Parkaas, Jim
    Södra Cell AB.
    Albertsson, Ann-Christine
    KTH, School of Chemical Science and Engineering (CHE), Fibre and Polymer Technology, Polymer Technology.
    Edlund, Ulrica
    KTH, School of Chemical Science and Engineering (CHE), Fibre and Polymer Technology, Polymer Technology.
    Utilization of a wood hydrolysate2007Patent (Other (popular science, discussion, etc.))
  • 21.
    Dånmark, Staffan
    et al.
    KTH, School of Chemical Science and Engineering (CHE), Fibre and Polymer Technology, Polymer Technology.
    Finne-Wistrand, Anna
    KTH, School of Chemical Science and Engineering (CHE), Fibre and Polymer Technology, Polymer Technology.
    Edlund, Ulrica
    KTH, School of Chemical Science and Engineering (CHE), Fibre and Polymer Technology, Polymer Technology.
    Albertsson, Ann-Christine
    KTH, School of Chemical Science and Engineering (CHE), Fibre and Polymer Technology, Polymer Technology.
    Mustafa, Kamal
    Insititutt for klinisk Odontologi, Medicinska och Odontologiska Fakulteten, Universitetet i Bergen, Norge.
    Enhanced Osteoconductivity of Degradable co-Polyester Scaffolds through Covalent Immobilization of BMP-2Manuscript (preprint) (Other academic)
  • 22.
    Edlund, Ulrica
    KTH, School of Chemical Science and Engineering (CHE), Fibre and Polymer Technology.
    Biomass conversion into functional bioplastics and gels2017In: Abstract of Papers of the American Chemical Society, ISSN 0065-7727, Vol. 253Article in journal (Other academic)
  • 23.
    Edlund, Ulrica
    KTH, Superseded Departments, Polymer Technology.
    Design of new biodegradable polymer matrices for controlled drug delivery2000Doctoral thesis, comprehensive summary (Other scientific)
    Abstract [en]

    Conventional drug administration technologies display poorcontrollability, and lead to high plasma concentrations andshort duration times, which frequently lead to adverse effects.Controlled release technology aims at predictable andreproducible delivery of an active substance over an extendedperiod of time, yielding optimal response and prolongedefficiency, and thus offering considerable improvement of manytreatments. A powerful approach to controlled drug delivery isthe incorporation of the drug into a biodegradable polymericmatrix, which distributes the active substance in a controlledand sustained fashion as the polymer erodes.

    This thesis describes the design of novel biodegradablepolymer matrices for controlled and sustained drug delivery.New functional and biodegradable materials with variableproperties were obtained by homopolymer blending andcopolymerization of building blocks with specific, desirableproperties; poly(adipic anhydride) (PAA), poly(trimethylenecarbonate) (PTMC), poly(1,5-dioxepan-2-one) (PDXO),poly(L-lactide) (PLLA), poly(D,L-lactide) (PDLLA), andpoly(L-lactide-co-1,5-dioxepan-2-one) (P(L-LA-co-DXO).Techniques were developed for the preparation of drug-releasingmatrices in the form of films and microspheres. Variousanalysis techniques, including Differential ScanningCalorimetry,1H-Nuclear Magnetic Resonance, InfraredSpectrometry, Scanning Electron Microscopy, Size ExclusionChromatography and UV-VIS Spectroscopy, were used forcharacterization.

    Microspheres encapsulating therapeutic substances wereprepared from P(L-LA-co-DXO) and blends of PDXO with PLLA orPDLLA. The properties, storage stability,degradation and drugrelease characteristics of these matrices were explored,compared and evaluated with special regard to the morphologyand its impact on thein vitrobehavior. Sustained release of drugs wasobtained. The mode of release was strongly influenced by thehydrophilicity of the drug, and by the copolymer/blendcomposition and morphology. The lactide:DXO composition wasproven to be a versatile tool to control the morphology and inturn the rates and pattern of erosion and diffusion ofencapsulated agents from the matrices.

    Films were prepared from PTMC-PAA blends, in which PAA actedas a plasticizer. Loss of the fast-degrading PAA componentenhanced the porosity and hydration of the slow-degrading PTMC.A statistical full factorial model was designed to elucidatethe influence of matrix parameters and their interactions. ThePTMC-PAA ratio, the molecular weight of the PTMC, andinteractions amongst these factors significantly influenced therelease performance, mass loss and degree of plasticization andthe relationships obtained enabled the erosion and drug releasepattern to be predicted and controlled. Moisture uptake,storage stability at different relative humidities, and thesterilizability were determined to further explore theversatility of PTMC-PAA matrices. Thein vivolocal tissue response and biocompatibility ofPTMC-PAA implants was assessed in the anterior chamber ofrabbits eyes for 1 month. PTMC-rich matrices displayed goodbiocompatibility.

    Key factors that regulate the biological activity of thesepolymeric vehicles were identified as drug solubility,composition, molecular weight, stereochemical configuration,and morphology. By careful design, the degradation and drugrelease characteristics, e.g. kinetics and duration, can bealtered over a broad spectrum. This study shows that structuralchanges of the polymer backbone, and the modeling ofcomposition and morphology provide powerful means of tailoringsystems for specific applications.

    Keywords: controlled release, drug delivery, microspheres,polylactide, poly(1,5-dioxepan-2-one), poly(adipic anhydride),poly(trimethylene carbonate), degradation, blends

  • 24.
    Edlund, Ulrica
    et al.
    KTH, Superseded Departments, Polymer Technology.
    Albertsson, A. C.
    Degradable polymer microspheres for controlled drug delivery2002In: Advances in Polymer Science, ISSN 0065-3195, E-ISSN 1436-5030, Vol. 157, p. 67-112Article, review/survey (Refereed)
    Abstract [en]

    Controlled drug delivery technology is concerned with the systematic release of a pharmaceutical agent to maintain a therapeutic level of the drug in the body for a sustained period of time. This may be achieved by incorporating the therapeutic agent into a degradable polymer vehicle, releasing the agent continuously as the matrix erodes. This review is concerned with degradable polymers for use in controlled drug delivery with emphasis on the preparation, applications, biocompatibility, and stability of microspheres from hydrolytically degradable polymers.

  • 25.
    Edlund, Ulrica
    et al.
    KTH, School of Chemical Science and Engineering (CHE), Fibre and Polymer Technology, Polymer Technology.
    Albertsson, Ann-Christine
    KTH, School of Chemical Science and Engineering (CHE), Fibre and Polymer Technology, Polymer Technology.
    A controlled radical polymerization route to polyepoxidated grafted hemicellulose materials2014In: Polimery, ISSN 0032-2725, Vol. 59, no 1, p. 60-65Article in journal (Refereed)
    Abstract [en]

    Polyfunctional copolymers were prepared from the major softwood hemicellulose polysaccharide, i.e. O-acetylated galactoglucomannan (AcGGM) through a grafting-from controlled radical polymerization. AcGGM was functionalized with brominated pendant groups that served as initiating species in the subsequent Cu(0) mediated radical polymerization of glycidyl methacrylate (GMA). A linear relationship of ln[GMA](0)/[GMA] (the index 0 refers to the initial value) versus reaction time up to conversions of 80 % suggests a first order rate of propagation and a "living" polymerization.

  • 26.
    Edlund, Ulrica
    et al.
    KTH, School of Chemical Science and Engineering (CHE), Fibre and Polymer Technology.
    Albertsson, Ann-Christine
    KTH, School of Chemical Science and Engineering (CHE), Fibre and Polymer Technology.
    A microspheric system: Hemicellulose-based hydrogels2008In: Journal of bioactive and compatible polymers (Print), ISSN 0883-9115, E-ISSN 1530-8030, Vol. 23, no 2, p. 171-186Article in journal (Refereed)
    Abstract [en]

    Hydrogel microspheres were prepared from the major softwood hemicellulose polysaccharide acetylated galactoglucomannan. The dry and swollen morphology was assessed by scanning electron microscopy. The microspheres were loaded with either a small hydrophilic substance ( caffeine) or a macromolecular model protein ( bovine serum albumin) and afforded diffusion controlled release in vitro. Statistical multivariate analysis was used to systematically determine the influence and significance of the hydrogel composition, the crosslinking density, and the dimensions of the incorporated substance on the microsphere size and release rate.

  • 27.
    Edlund, Ulrica
    et al.
    KTH, Superseded Departments, Polymer Technology.
    Albertsson, Ann-Christine
    KTH, Superseded Departments, Polymer Technology.
    Copolymerization and polymer blending of trimethylene carbonate and adipic anhydride for tailored drug delivery1999In: Journal of Applied Polymer Science, ISSN 0021-8995, E-ISSN 1097-4628, Vol. 72, no 2, p. 227-239Article in journal (Refereed)
    Abstract [en]

    The copolymerization in bulk and solution of trimethylene carbonate (TMC) with adipic anhydride (AA) as well as the blending of homopolymers are described. We show experimentally that the components are not copolymerizable but partially miscible, forming a microscopic dispersion without any visible signs of phase separation. Poly(adipic anhydride) (PAA) functions as a plasticizer, permitting an increase in the erosion rate by increasing the porosity and hydration. Drug delivery from the blends was evaluated. A statistical factorial model was designed to explore the influence of three important blend parameters and their interactions, making it possible to predict the erosion and drug-release behavior of the blend matrices. The PAA:poly(trimethylene carbonate) (PTMC) ratio and molecular weight of the polycarbonate component significantly influence the drug-release performance, mass loss, and degree of plasticization. The interaction among these factors also influences the blend properties. Plasticization of PTMC enhances the drug release to an extent that is dependent on the amount of PAA used. We demonstrate that blending offers a convenient alternative to copolymerization for the preparation of polymer matrices with predictable drug delivery.

  • 28.
    Edlund, Ulrica
    et al.
    KTH, School of Chemical Science and Engineering (CHE), Fibre and Polymer Technology, Polymer Technology.
    Albertsson, Ann-Christine
    KTH, School of Chemical Science and Engineering (CHE), Fibre and Polymer Technology, Polymer Technology.
    Green living radical polymerization from hemicellulose-based macroinitiators2012In: Abstract of Papers of the American Chemical Society, ISSN 0065-7727, Vol. 244Article in journal (Other academic)
  • 29.
    Edlund, Ulrica
    et al.
    KTH, School of Chemical Science and Engineering (CHE), Fibre and Polymer Technology.
    Albertsson, Ann-Christine
    KTH, School of Chemical Science and Engineering (CHE), Fibre and Polymer Technology.
    Hemicellulose-rich materials derived from wood pre-hydrolysis2014In: Abstract of Papers of the American Chemical Society, ISSN 0065-7727, Vol. 247, p. 199-CELL-Article in journal (Other academic)
  • 30.
    Edlund, Ulrica
    et al.
    KTH, School of Chemical Science and Engineering (CHE), Fibre and Polymer Technology, Polymer Technology.
    Albertsson, Ann-Christine
    KTH, School of Chemical Science and Engineering (CHE), Fibre and Polymer Technology, Polymer Technology.
    Macroinitiator Halide Effects in Galactoglucomannan-Mediated Single Electron Transfer-Living Radical Polymerization2011In: Journal of Polymer Science Part A: Polymer Chemistry, ISSN 0887-624X, E-ISSN 1099-0518, Vol. 49, no 19, p. 4139-4145Article in journal (Refereed)
    Abstract [en]

    Chloro (Cl)- and bromo (Br)-functionalized macroinitiators were successfully prepared from the softwood hemicellulose O-acetylated galactoglucomannan (AcGGM) and then explored and evaluated with respect to their ability and efficiency of initiating single electron transfer-living radical polymerization (SET-LRP). Both halogenated species effectively initiate SET-LRP of an acrylate and a methacrylate monomer, respectively, yielding brushlike AcGGM graft copolymers, where the molecular weights are accurately controlled via the monomer:macroinitiator ratio and polymerization time over a broad range: from oligomeric to ultrahigh. The nature of the halogen does not influence the kinetics of polymerization strongly, however, for acrylate graft polymerization, AcGGM-Cl gives a somewhat higher rate constant of propagation, while methacrylate grafting proceeds slightly faster when the initiating species is AcGGM-Br. For both monomers, the macroinitiator efficiency is superior in the case of AcGGM-Br.

  • 31.
    Edlund, Ulrica
    et al.
    KTH, Superseded Departments, Polymer Technology.
    Albertsson, Ann-Christine
    KTH, Superseded Departments, Polymer Technology.
    Microspheres from poly(D,L-lactide)/poly(1,5-dioxepan-2-one) miscible blends for controlled drug delivery2000In: Journal of bioactive and compatible polymers (Print), ISSN 0883-9115, E-ISSN 1530-8030, Vol. 15, no 3, p. 214-229Article in journal (Refereed)
    Abstract [en]

    Novel biodegradable microspheres were designed from blends of poly(D,L-lactide) (PDLLA) and poly(1,5-dioxepan-2-one) (PDXO). The addition of PDXO to PDLLA yielded a more pliable and versatile matrix, where the properties can be controlled by means of composition. The components were fully miscible and formed homogeneous, amorphous, smooth and dense microspheres. Blend composition was a vital factor in determining the blend properties, morphology and in vitro degradation. Diclofenac sodium, a non-steroidal anti-inflammatory drug, was incorporated into PDLLA-PDXO microspheres of various composition ratios. Sustained release of drug was obtained. The degradation and release rates of PDLLA-PDXO microspheres were dependent on the blend composition, providing a powerful means of controlling drug delivery.

  • 32.
    Edlund, Ulrica
    et al.
    KTH, Superseded Departments, Polymer Technology.
    Albertsson, Ann-Christine
    KTH, Superseded Departments, Polymer Technology.
    Morphology engineering of a novel poly(L-lactide)/poly(1,5-dioxepan-2-one) microsphere system for controlled drug delivery2000In: Journal of Polymer Science Part A: Polymer Chemistry, ISSN 0887-624X, E-ISSN 1099-0518, Vol. 38, no 5, p. 786-796Article in journal (Refereed)
    Abstract [en]

    Morphology is presented as a powerful tool to control the in vitro degradation and drug release characteristics of novel drug delivery microspheres prepared from homopolymer blends of 1,5-dioxepan-2-one, DXO, and L-lactide, L-LA. Their performance in this respect was compared to analogous P(L-LA-co-DXO) microspheres. Blends formed denser and less porous microspheres with a higher degree of matrix crystallinity than copolymers of corresponding L-LA:DXO composition. The morphology differences of blends and copolymers, further adjustable by means of component ratio, are shown to have a vital impact on the in vitro performance. Sustained drug delivery was obtained from both copolymers and blends. Molecular weight; loss was retarded and diffusion-mediated release was inhibited in the latter case, further delaying the release process. The effects of storage on the physicochemical properties of these systems were evaluated under desiccated and moist conditions for 5 months. Storage-induced physicochemical changes, such as matrix crystallization and molecular weight decrease, were accelerated at higher relative humidities. P(L-LA-co-DXO) demonstrated higher moisture sensitivity than a PLLA-PDXO blend of corresponding composition. The more crystalline and dense morphology of blend microspheres may thus be considered an improvement of the storage stability.

  • 33.
    Edlund, Ulrica
    et al.
    KTH, School of Chemical Science and Engineering (CHE), Fibre and Polymer Technology, Polymer Technology.
    Albertsson, Ann-Christine
    KTH, School of Chemical Science and Engineering (CHE), Fibre and Polymer Technology.
    New approaches to the design of hybrid materials from hemicelluloses-rich resources2011In: Abstract of Papers of the American Chemical Society, ISSN 0065-7727, Vol. 241Article in journal (Other academic)
  • 34.
    Edlund, Ulrica
    et al.
    KTH, Superseded Departments, Polymer Technology.
    Albertsson, Ann-Christine
    KTH, Superseded Departments, Polymer Technology.
    Novel drug delivery microspheres from poly(1,5-dioxepan-2-one-co-L-lactide)1999In: Journal of Polymer Science Part A: Polymer Chemistry, ISSN 0887-624X, E-ISSN 1099-0518, Vol. 37, no 12, p. 1877-1884Article in journal (Refereed)
    Abstract [en]

    Novel microspheres from copolymers of 1,5-dioxepan-2-one (DXO) and L-lactide (L-LA) were prepared by oil-in-water solvent evaporation and oil-in-oil solvent removal. The two preparation techniques were evaluated for sphere formulation and incorporation of two different drugs. Sustained release of these therapeutic substances was obtained. The consequences of altering the DXO : LA ratio, preparation method, and drug hydrophilicity were explored and identified as factors governing sphere quality, in vitro degradation, and drug release characteristics. We show that these relationships provide a powerful means of controlling the microsphere performance.

  • 35.
    Edlund, Ulrica
    et al.
    KTH, Superseded Departments, Polymer Technology.
    Albertsson, Ann-Christine
    KTH, Superseded Departments, Polymer Technology.
    Polyesters based on diacid monomers2003In: Advanced Drug Delivery Reviews, ISSN 0169-409X, E-ISSN 1872-8294, Vol. 55, no 4, p. 585-609Article, review/survey (Refereed)
    Abstract [en]

    Polymers with ester linkages in their main chain comprise a family of polymers with immense diversity and versatility. This review deals with the preparation of such polymers from dicarboxylic acid monomers, and the result in terms of properties and applicability. Polyesters alone, and their copolymers with amides, anhydrides, urethanes, imides, ethers or other functional groups, offer countless opportunities to tune the properties of the resulting material within a broad range. Of particular interest is the inherent biodegradability of the ester linkage. Biodegradability is sought after in a wide range of applications, above all in the preparation of environmentally friendly polymers and biomedical materials for temporary surgical use and in drug delivery.

  • 36.
    Edlund, Ulrica
    et al.
    KTH, School of Chemical Science and Engineering (CHE), Fibre and Polymer Technology.
    Albertsson, Ann-Christine
    KTH, School of Chemical Science and Engineering (CHE), Fibre and Polymer Technology.
    SET-LRP Goes "Green": Various Hemicellulose Initiating Systems Under Non-Inert Conditions2012In: Journal of Polymer Science Part A: Polymer Chemistry, ISSN 0887-624X, E-ISSN 1099-0518, Vol. 50, no 13, p. 2650-2658Article in journal (Refereed)
    Abstract [en]

    Robust and versatile controlled radical polymerization, also in air, was achieved via single electron transfer living radical polymerization (SET-LRP) initiated by purposely designed hemicellulose-derived macroinitiators. The efficiency of the substitution reaction, converting the polysaccharides into bromo-multifunctionalized initiators, as well as the rate of subsequent induced polymerizations of methyl acrylate were controlled by the hemicellulose repeating unit structure, branching pattern, and molecular weight. Macroinitiators with mannan-based backbones induce SET-LRP with somewhat higher apparent rate constants than xylan-derived analogues, increasing by a factor two to three when raising the reaction temperature from 25 to 40 degrees C. The presence of lignin in a non-purified xylan fraction did not impair its viability as a macroinitiator. Hemicellulose-initiated SET-LRP was feasible in air, proceeding with comparable or somewhat higher apparent rate constants than when conducted under deoxygenated conditions.

  • 37.
    Edlund, Ulrica
    et al.
    KTH, Superseded Departments, Polymer Technology.
    Albertsson, Ann-Christine
    KTH, Superseded Departments, Polymer Technology.
    Singh, K
    Fogelberg, I
    Lundgren, O
    Sterilization, storage stability and in vivo biocompatibility of poly(trimethylene carbonate)/poly(adipic anhydride) blends2000In: Biomaterials, ISSN 0142-9612, E-ISSN 1878-5905, Vol. 21, no 9, p. 945-955Article in journal (Refereed)
    Abstract [en]

    Biodegradable blends of poly(trimethylene carbonate) (PTMC) and poly(adipic anhydride) (PAA) have been proven to be strong candidates for controlled drug delivery polymers in vitro. We now report on the stability, sterilizability and in vivo local tissue response of these matrices. Blend matrices were sterilized by beta-radiation or ethylene oxide gas treatment, stored at different times and temperatures, and analyzed for changes in physicochemical properties. Moisture uptake at different relative humidities and storage times was determined. Sterilization procedures induced hydrolysis of the matrices. Ethylene oxide gas sterilization had a significantly more marked effect upon the matrix properties than radiation treatment. The onset of degradation was reflected in a decrease of crystallinity and molecular weight along with a change of blend composition. A similar onset of matrix degradation was observed upon storage in air. The physicochemical properties of the blends were well preserved upon storage under argon atmosphere. Biocompatibility of PTMC/PAA implants was assessed in the anterior chamber of rabbits eyes for 1 month. At selected post-operative time points, aqueous humor was analyzed for white blood cells and the corneal thickness was measured. The results suggest good biocompatability of PTMC-rich matrices, whereas fast eroding PAA-rich matrices caused inflammatory responses, due to a burst release of degradation products.

  • 38.
    Edlund, Ulrica
    et al.
    KTH, School of Chemical Science and Engineering (CHE), Fibre and Polymer Technology.
    Danmark, Staffan
    Albertsson, Ann-Christine
    KTH, School of Chemical Science and Engineering (CHE), Fibre and Polymer Technology.
    A strategy for the covalent functionalization of resorbable polymers with heparin and osteoinductive growth factor2008In: Biomacromolecules, ISSN 1525-7797, E-ISSN 1526-4602, Vol. 9, no 3, p. 901-905Article in journal (Refereed)
    Abstract [en]

    The chemical strategy presented herein is the nondestructive preparation of resorbable polymer scaffolds with heparin covalently bonded to the surface and an osteoinductive growth factor, recombinant human bone morphogenetic protein-2, immobilized in the heparin layer. The coupling scheme involves functionalization of surfaces by grafting in the vapor phase with poly(L-lactide) and poly (e-caprolactone) films chosen as representative substrates. The biocompatibility of functionalized surfaces was verified by a much improved attachment and proliferation of mesenchymal stem cells (MSC).

  • 39.
    Edlund, Ulrica
    et al.
    KTH, School of Chemical Science and Engineering (CHE), Fibre and Polymer Technology.
    Källrot, Martina
    KTH, School of Chemical Science and Engineering (CHE), Fibre and Polymer Technology.
    Albertsson, Ann-Christine
    KTH, School of Chemical Science and Engineering (CHE), Fibre and Polymer Technology.
    Nano Patterened Covalent Surface Modification of Poly(ε-caprolactone)2005In: Israel Journal of Chemistry, ISSN 0021-2148, Vol. 45, no 4, p. 429-435Article in journal (Refereed)
    Abstract [en]

    Using our new vapor-phase grafting technique, we have simultaneously chemically and physically modified the surface of poly(e-caprolactone) (PCL) films. The substrates were covered with nano patterned silicone rubber stamps and subjected to UV irradiation in the presence of the solvent-free vapor phase of either N-vinyl pyrrolidone or maleic anhydride, and a photoinitiator, under reduced pressure. The treated films display a surface pattern of grafted channels of 450-nm width, as confirmed by AFM and SEM. The grafting was further verified with ATR-FTIR, and contact angle measurements show an increased wettability of the surfaces.

  • 40.
    Edlund, Ulrica
    et al.
    KTH, School of Chemical Science and Engineering (CHE), Fibre and Polymer Technology.
    Källrot, Martina
    KTH, School of Chemical Science and Engineering (CHE), Fibre and Polymer Technology.
    Albertsson, Ann-Christine
    KTH, School of Chemical Science and Engineering (CHE), Fibre and Polymer Technology.
    Single-Step Covalent Functionalization of Polylactide Surfaces2005In: Journal of the American Chemical Society, ISSN 0002-7863, E-ISSN 1520-5126, Vol. 127, no 24, p. 8865-8871Article in journal (Refereed)
    Abstract [en]

    A single-step, nondestructive, and versatile technique for the grafting and chemical surface modification of biodegradable polymers such as polylacticle is described. The substrates are subjected to the vapor phase of any of three investigated vinyl monomers: acrylamide, maleic anhydride, and N-vinylpyrrolidone, and grafting is induced by photoinitiation of benzophenone under solvent free conditions. The modified surfaces exhibit higher wettability, and the grafting is verified by X-ray photoelectron spectroscopy, attenuated total reflection Fourier-transform IR, contact-angle measurements, and scanning electron microscopy. The graft-chain pendant groups remain functional and can subsequently be modified so that a tailor-made surface with desired properties may be achieved.

  • 41.
    Edlund, Ulrica
    et al.
    KTH, School of Engineering Sciences in Chemistry, Biotechnology and Health (CBH), Fibre- and Polymer Technology. RISE Bioecon, Drottning Kristinas Vag 61, SE-11428 Stockholm, Sweden..
    Lagerberg, Tove
    Alander, Eva
    Admicellar Polymerization Coating of CNF Enhances Integration in Degradable Nanocomposites2019In: Biomacromolecules, ISSN 1525-7797, E-ISSN 1526-4602, Vol. 20, no 2, p. 684-692Article in journal (Refereed)
    Abstract [en]

    A water-based one-pot synthesis strategy for converting cellulose nanofibrils (CNF) into a hydrophobic and processable biopolymer grade is devised. CNF was chemically modified through admicellar polymerization, producing fibrils coated with fatty acrylate polymers. The proposed modification targets a change in the interfibrillar interactions and improved CNF compatibility with a degradable plastic composite matrix, poly(butylene adipate-co-terephthalate), PBAT in composites prepared by melt extrusion. CNF had a clear reinforcing effect on PBAT, increasing Young's modulus by at least 35% and 169% at 5 and 20% (w/w) CNF content, respectively. However, unmodified CNF showed aggregation, poor adhesion in the matrix, and severely impaired the ductility of PBAT. CNF modified by admicellar polymerization was homogeneously dispersed in the PBT matrix and showed significantly better preservation of the elongation properties compared to unmodified CNF, especially at 5% (w/w) addition level.

  • 42.
    Edlund, Ulrica
    et al.
    KTH, School of Engineering Sciences in Chemistry, Biotechnology and Health (CBH), Fibre- and Polymer Technology.
    Navarro, Julien R. G.
    KTH, School of Engineering Sciences in Chemistry, Biotechnology and Health (CBH), Fibre- and Polymer Technology.
    Alander, Eva
    RISE Bioecon, Stockholm, Sweden..
    Engineering the surface chemistry of nanocelluloses for material applications2019In: Abstracts of Papers of the American Chemical Society, ISSN 0065-7727, Vol. 257Article in journal (Other academic)
  • 43.
    Edlund, Ulrica
    et al.
    KTH, School of Chemical Science and Engineering (CHE), Fibre and Polymer Technology.
    Rodriguez-Emmenegger, Cesar
    Brynda, Eduard
    Albersson, Ann-Christine
    KTH, School of Chemical Science and Engineering (CHE), Fibre and Polymer Technology.
    Self-assembling zwitterionic carboxybetaine copolymers via aqueous SET-LRP from hemicellulose multi-site initiators2012In: Polymer Chemistry, ISSN 1759-9954, Vol. 3, no 10, p. 2920-2927Article in journal (Refereed)
    Abstract [en]

    The zwitterionic carboxybetaines, (3-methacryloylamino-propyl)-(2-carboxy-ethyl)-dimethyl-ammonium (CBMAA-3) and (3-acryloylamino-propyl)-(2-carboxy-ethyl)-dimethyl-ammonium (CBAA-3), were successfully grafted from a galactoglucomannan macroinitiator. The macroinitiator was prepared from the hemicellulose acetylated galactoglucomannan functionalised with alpha-bromoisobutyric acid. The polymerisation of the betaines was efficiently carried out by a Cu(0) wire catalysed single electron-transfer living radical polymerisation (SET-LRP) in aqueous solution yielding water-soluble graft copolymers and nearly pseudo-first order kinetics suggesting a good degree of control over the polymerisation process. The graft copolymers spontaneously self-assembled in aqueous solution into well-defined nanoparticles highly stable in aqueous media.

  • 44.
    Edlund, Ulrica
    et al.
    KTH, School of Chemical Science and Engineering (CHE), Fibre and Polymer Technology, Polymer Technology.
    Sauter, Tilman
    KTH, School of Chemical Science and Engineering (CHE), Fibre and Polymer Technology, Polymer Technology.
    Albertsson, Ann-Christine
    KTH, School of Chemical Science and Engineering (CHE), Fibre and Polymer Technology, Polymer Technology.
    Covalent VEGF protein immobilization on resorbable polymeric surfaces2011In: POLYMERS FOR ADVANCED TECHNOLOGIES , 2011, Vol. 22, no 1, p. 166-171Conference paper (Refereed)
    Abstract [en]

    Vascular endothelial growth factor (VEGF) type protein, a potent angiogenic effector molecule, was successfully covalently immobilized onto the surfaces of the resorbable polymers poly(L-lactic acid) (PLLA) and poly(epsilon-caprolactone) through a three-step strategy. The surfaces were first covalently grafted with poly(acrylic acid) using non-destructive and solvent-free vapor-phase grafting. A diamine spacer was coupled to the carboxylic acid pendant groups on the graft chains using 1-ethyl-3-(3-dimethylaminopropyl)-carbodiimide hydrochloride/N-hydroxysuccinimide chemistry and VEGF was finally covalently attached to the amine linkers. The chemistry and topography of the modified substrates were quantitatively and qualitatively verified with X-ray photoelectron spectroscopy, attenuated total reflectance-Fourier transform infrared spectrometry, UV-VIS, scanning electron microscopy, and enzyme-linked immunosorbent assay.

  • 45.
    Edlund, Ulrica
    et al.
    KTH, School of Chemical Science and Engineering (CHE), Fibre and Polymer Technology, Polymer Technology.
    Sauter, Tilman
    KTH, School of Chemical Science and Engineering (CHE), Fibre and Polymer Technology, Polymer Technology.
    Albertsson, Ann-Christine
    KTH, School of Chemical Science and Engineering (CHE), Fibre and Polymer Technology, Polymer Technology.
    Covalent VEGF protein immobilization on resorbable polymeric surfaces2011In: Polymers for Advanced Technologies, ISSN 1042-7147, E-ISSN 1099-1581, Vol. 22, no 12, p. 2368-2373Article in journal (Refereed)
    Abstract [en]

    Vascular endothelial growth factor type protein (VEGF), a potent angiogenic effector molecule, was successfully covalently immobilized onto the surfaces of the resorbable polymers poly(L-lactic acid) (PLLA) and poly(epsilon-caprolactone) (PCL) through a three-step strategy. The surfaces were first covalently grafted with poly(acrylic acid) using non-destructive and solvent free vapor-phase grafting. A diamine spacer was coupled to the carboxylic acid pendant groups on the graft chains using EDC/NHS chemistry and VEGF was finally covalently attached to the amine linkers. The chemistry and topography of the modified substrates were quantitatively and qualitatively verified with XPS, ATR-FTIR, UV-VIS, SEM, and ELISA.

  • 46.
    Edlund, Ulrica
    et al.
    KTH, School of Chemical Science and Engineering (CHE), Fibre and Polymer Technology, Polymer Technology.
    Svensson, Marie
    KTH, School of Chemical Science and Engineering (CHE), Fibre and Polymer Technology, Polymer Technology.
    Albertsson, Ann-Christine
    KTH, School of Chemical Science and Engineering (CHE), Fibre and Polymer Technology, Polymer Technology.
    Microsphere valorization of forestry derived hydrolysates2012In: European Polymer Journal, ISSN 0014-3057, E-ISSN 1873-1945, Vol. 48, no 2, p. 372-383Article in journal (Refereed)
    Abstract [en]

    A value-adding approach to the material utilization of non-cellulosic polysaccharides (NCPs) released from the lignocellulosic feedstock was realized via the formulation of renewable microspheres from wood hydrolysates using a purposely elaborated all edible water-in-oil emulsion technique. Four compositionally different hemicellulose rich wood hydrolysates were recovered from process waters in pulping and other hydrothermal treatments of hardwood and softwood. Multivariate screening designs were employed allowing for the identification and quantitation of significant process parameters and interaction effects governing the conversion of hydrolysates into small, smooth and well-defined microspheres with narrow size dispersity.

  • 47.
    Edlund, Ulrica
    et al.
    KTH, School of Chemical Science and Engineering (CHE), Fibre and Polymer Technology, Polymer Technology.
    Yu, Yang
    Ryberg, Yingzhi Zhu
    KTH, School of Chemical Science and Engineering (CHE), Fibre and Polymer Technology, Polymer Technology.
    Krause-Rehberg, Reinhard
    Albertsson, Ann-Christine
    KTH, School of Chemical Science and Engineering (CHE), Fibre and Polymer Technology, Polymer Technology.
    Positron Lifetime Reveals the Nano Level Packing in Complex Polysaccharide-Rich Hydrolysate Matrixes2012In: Analytical Chemistry, ISSN 0003-2700, E-ISSN 1520-6882, Vol. 84, no 8, p. 3676-3681Article in journal (Refereed)
    Abstract [en]

    Positron annihilation lifetime spectroscopy (PALS) was used to quantify the free volume and molecular packing in hydrolysate and hemicellulose-based barriers films, derived from process streams during wood processing operations. These hydrolysate films, comprising a fair share of lignin coexisting with poly- and oligo-saccharides, have very low but variable oxygen permeability but differ among themselves with respect to barrier performance as well as molecular weight, degree of branching, and monosaccharide residue main chain composition. From PALS measurements on hydrolysates, the free volume hole radius (r(h)), radius distributions (n(r(h))), volume-weighted hole sizes (<v(h)>(v)), and hole volume distributions (g(v(h))) were calculated showing that the hydrolysate matrixes are very densely packed with small holes. The results show a clear relationship between hydrolysate molecular architecture and composition, the nanolevel molecular packing, and the ability of suppressing the diffusion of oxygen through the film.

  • 48.
    Edlund, Ulrica
    et al.
    KTH, School of Chemical Science and Engineering (CHE), Fibre and Polymer Technology, Polymer Technology.
    Zhu Ryberg, Yingzhi
    KTH, School of Chemical Science and Engineering (CHE), Fibre and Polymer Technology, Polymer Technology.
    Albertsson, Ann-Christine
    KTH, School of Chemical Science and Engineering (CHE), Fibre and Polymer Technology, Polymer Technology.
    Barrier Films from Renewable Forestry Waste2010In: Biomacromolecules, ISSN 1525-7797, E-ISSN 1526-4602, Vol. 11, no 9, p. 2532-2538Article in journal (Refereed)
    Abstract [en]

    Biobased free-standing films and coatings with low oxygen permeability were designed from a wood hydrolysate according to a recovery and formulation procedure that provides added value to wood converting industrial processes. Wood components released to the wastewater in the hydrothermal treatment of spruce wood were recovered and converted to an oligo- and polysaccharide-rich, noncellulosic fraction that was utilized in film formulations in a range of concentrations and compositions. Free-standing smooth and transparent films as well as coatings on thin PET were prepared and characterized with respect to oxygen permeability, tensile properties, structure, and water vapor transmission. With oxygen permeabilities as low as below I cm(3) mu m m(-2) day(-1) kPa(-1) and with adequate mechanical properties, the films and coatings show promising property profiles for renewable packaging applications.

  • 49. Ferrari, Elena
    et al.
    Ranucci, Elisabetta
    Edlund, Ulrica
    KTH, School of Chemical Science and Engineering (CHE), Fibre and Polymer Technology.
    Albertsson, Ann-Christine
    KTH, School of Chemical Science and Engineering (CHE), Fibre and Polymer Technology.
    Design of renewable poly(amidoamine)/hemicellulose hydrogels for heavy metal adsorption2015In: Journal of Applied Polymer Science, ISSN 0021-8995, E-ISSN 1097-4628, Vol. 132, no 12, p. 41695-Article in journal (Refereed)
    Abstract [en]

    Renewable poly(amidoamine)/hemicellulose hydrogels were prepared from O-acetylated galactoglucomannan (AcGGM)-rich biomass and shown to display a significantly high adsorption capacity for Cu2+, Cd2+, Pb-2+,Pb- Zn2+, Ni2+, Co2+, and . Two different acrylamido end-capped poly(amidoamine) oligomers (PAA) were prepared and covalently immobilized onto an in situ formed polysaccharide network via water-based free radical graft copolymerization and cross-linking. The synthetic approach was shown to be viable when using a highly purified AcGGM or a crude spruce hydrolysate, an AcGGM and lignin containing biomass fraction as a reactant. Homogeneous reaction mixtures were obtained in both cases with polysaccharide contents up to 20% by weight. Oscillatory shear measurements indicated a predominantly solid-like behavior of the hydrogels with an increase in shear storage modulus with increasing cross-link density. The mechanical integrity of the PAA/hemicellulose hydrogels showed higher water swelling capacity and less fragility than the parent PAA hydrogels and they retained the heavy metal ion absorption ability of the PAA component, even in the presence of the least purified hemicellulose fraction.

  • 50. Galkin, Maxim V.
    et al.
    Di Francesco, Davide
    Edlund, Ulrica
    KTH, School of Chemical Science and Engineering (CHE), Fibre and Polymer Technology.
    Samec, Joseph S. M.
    Sustainable sources need reliable standards2017In: Faraday discussions (Online), ISSN 1359-6640, E-ISSN 1364-5498, Vol. 202, p. 281-301Article in journal (Refereed)
    Abstract [en]

    This review discusses the challenges within the research area of modern biomass fractionation and valorization. The current pulping industry focuses on pulp production and the resulting cellulose fiber. Hemicellulose and lignin are handled as low value streams for process heat and the regeneration of process chemicals. The paper and pulp industry have therefore developed analytical techniques to evaluate the cellulose fiber, while the other fractions are given a low priority. In a strive to also use the hemicellulose and lignin fractions of lignocellulosic biomass, moving towards a biorefining concept, there are severe shortcomings with the current pulping techniques and also in the analysis of the biomass. Lately, new fractionation techniques have emerged which valorize a larger extent of the lignocellulosic biomass. This progress has disclosed the shortcomings in the analysis of mainly the hemicellulose and lignin structure and properties. To move the research field forward, analytical tools for both the raw material, targeting all the wood components, and the generated fractions, as well as standardized methods for evaluating and reporting yields are desired. At the end of this review, a discourse on how such standardizations can be implemented is given.

123 1 - 50 of 117
CiteExportLink to result list
Permanent link
Cite
Citation style
  • apa
  • harvard1
  • ieee
  • modern-language-association-8th-edition
  • vancouver
  • Other style
More styles
Language
  • de-DE
  • en-GB
  • en-US
  • fi-FI
  • nn-NO
  • nn-NB
  • sv-SE
  • Other locale
More languages
Output format
  • html
  • text
  • asciidoc
  • rtf