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Finne Wistrand, AnnaORCID iD iconorcid.org/0000-0002-1922-128X
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Publications (10 of 104) Show all publications
Liu, H., Ahlinder, A., Yassin, M. A., Finne Wistrand, A. & Gasser, T. C. (2020). Computational and experimental characterization of 3D-printed PCL structures toward the design of soft biological tissue scaffolds. Materials & design, 188, Article ID 108488.
Open this publication in new window or tab >>Computational and experimental characterization of 3D-printed PCL structures toward the design of soft biological tissue scaffolds
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2020 (English)In: Materials & design, ISSN 0264-1275, E-ISSN 1873-4197, Vol. 188, article id 108488Article in journal (Refereed) Published
Abstract [en]

Degradable porous polymeric structures are attractive candidates for biological tissue scaffolds, and adequate mechanical, transport, chemical and biological properties determine their functionality. Aside from the properties of polymer-based materials, the scaffold's meso-structure controls its elasticity at the organ length-scale. This study investigated the effect of the meso-structure on scaffolds' mechanical and transport properties using finite element analysis (FEA) and computational fluid dynamics (CFD). A number of poly (ε-caprolactone) (PCL) - based scaffolds were 3D printed, analyzed by microcomputed tomography (micro-CT) and mechanically tested. We found that the gradient (G) and gradient and staggered (GS) meso-structure designs led to a higher scaffold permeability, a more homogeneous flow inside the scaffold, and a lower wall shear stress (WSS) in comparison with the basic (B) meso-structure design. The GS design resulted in scaffold stiffness as low as 1.07/0.97 MPa under compression/tension, figures that are comparative with several soft tissues. Image processing of micro-CT data demonstrated that the imposed meso-structures could have been adequately realized through 3D printing, and experimental testing validated FEA analysis. Our results suggest that the properties of 3D-printed PCL-based scaffolds can be tuned via meso-structures toward soft tissue engineering applications. The biological function of designed scaffolds should be further explored in-situ studies.

Place, publisher, year, edition, pages
Elsevier, 2020
Keywords
3D printing, Computational fluid dynamics, Finite element analysis, Meso-structure, Scaffold, Soft tissue engineering
National Category
Chemical Sciences
Identifiers
urn:nbn:se:kth:diva-267795 (URN)10.1016/j.matdes.2020.108488 (DOI)2-s2.0-85077922391 (Scopus ID)
Note

QC 20200220

Available from: 2020-02-20 Created: 2020-02-20 Last updated: 2020-02-20Bibliographically approved
Ahlinder, A., Fuoco, T., Morales-Lopez, A., Yassin, M. A., Mustafa, K. & Finne Wistrand, A. (2020). Nondegradative additive manufacturing of medical grade copolyesters of high molecular weight and with varied elastic response. Journal of Applied Polymer Science, 137(15), Article ID 48550.
Open this publication in new window or tab >>Nondegradative additive manufacturing of medical grade copolyesters of high molecular weight and with varied elastic response
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2020 (English)In: Journal of Applied Polymer Science, ISSN 0021-8995, E-ISSN 1097-4628, Vol. 137, no 15, article id 48550Article in journal (Refereed) Published
Abstract [en]

Although additive manufacturing through melt extrusion has become increasingly popular as a route to design scaffolds with complex geometries the technique if often limited by the reduction in molecular weight and the viscoelastic response when degradable aliphatic polyesters of high molecular weight are used. Here we use a melt extruder and fused filament fabrication printer to produce a reliable nondegradative route for scaffold fabrication of medical grade copolymers of L-lactide, poly(epsilon-caprolactone-co-L-lactide), and poly(L-lactide-co-trimethylene carbonate). We show that degradation is avoided using filament extrusion and fused filament fabrication if the process parameters are deliberately chosen based upon the rheological behavior, mechanical properties, and polymer composition. Structural, mechanical, and thermal properties were assessed throughout the process to obtain comprehension of the relationship between the rheological properties and the behavior of the medical grade copolymers in the extruder and printer. Scaffolds with a controlled architecture were achieved using high-molecular-weight polyesters exhibiting a large range in the elastic response causing negligible degradation of the polymers.

Place, publisher, year, edition, pages
WILEY, 2020
National Category
Chemical Sciences
Identifiers
urn:nbn:se:kth:diva-267140 (URN)10.1002/app.48550 (DOI)000508022900024 ()2-s2.0-85073154893 (Scopus ID)
Note

QC 20200217

Available from: 2020-02-17 Created: 2020-02-17 Last updated: 2020-02-17Bibliographically approved
Jain, S., Fuoco, T., Yassin, M. A., Mustafa, K. & Finne Wistrand, A. (2020). Printability and Critical Insight into Polymer Properties during Direct-Extrusion Based 3D Printing of Medical Grade Polylactide and Copolyesters. Biomacromolecules, 21(2), 388-396
Open this publication in new window or tab >>Printability and Critical Insight into Polymer Properties during Direct-Extrusion Based 3D Printing of Medical Grade Polylactide and Copolyesters
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2020 (English)In: Biomacromolecules, ISSN 1525-7797, E-ISSN 1526-4602, Vol. 21, no 2, p. 388-396Article, review/survey (Refereed) Published
Abstract [en]

Various 3D printing techniques currently use degradable polymers such as aliphatic polyesters to create well-defined scaffolds. Even though degradable polymers are influenced by the printing process, and this subsequently affects the mechanical properties and degradation profile, degradation of the polymer during the process is not often considered. Degradable scaffolds are today printed and cell-material interactions evaluated without considering the fact that the polymer change while printing the scaffold. Our methodology herein was to vary the printing parameters such as temperature, pressure, and speed to define the relationship between printability, polymer microstructure, composition, degradation profile during the process, and rheological behavior. We used high molecular weight medical-grade (co)polymers, poly(L-lactide-co-epsilon-caprolactone) (PCLA), poly(L-lactide-co-glycolide) (PLGA), and poly(D,L-lactide-co-glycolide) (PDLGA), with L-lactide content ranging from 25 to 100 mol %, for printing in an extrusion-based printer (3D Bioplotter). Optical microscopy confirmed that the polymers were printable at high resolution and good speed, until a certain degree of degradation. The results show also that printability can not be claimed just by optimizing printing parameters and highlight the importance of a careful analysis of how the polymer's structure and properties vary during printing. The polymers thermally decomposed from the first processing minute and caused a decrease in the average block length of the lactide blocks in the copolymers and generated lower crystallinity. Poly(L-lactide) (PLLA) and PCLA are printable at a higher molecular weight, less degradation before printing was possible, compared to PLGA and PDLGA, a result explained by the higher complex viscosity and more elastic polymeric melt of the copolymer containing glycolide (GA) and lactide (LA). In more detail, copolymers comprised of LA and epsilon-caprolactone (CL) formed lower molecular weight compounds over the course of printing, while the PLGA copolymer was more susceptible to intermolecular transesterification reactions, which do not affect the overall molecular weight, but cause changes in the copolymer microstructure. This results in a longer printing time for PLGA than PLLA and PCLA.

Place, publisher, year, edition, pages
AMER CHEMICAL SOC, 2020
National Category
Chemical Sciences
Identifiers
urn:nbn:se:kth:diva-269468 (URN)10.1021/acs.biomac.9b01112 (DOI)000513091100012 ()31566357 (PubMedID)2-s2.0-85073450017 (Scopus ID)
Note

QC 20200310

Available from: 2020-03-10 Created: 2020-03-10 Last updated: 2020-03-10Bibliographically approved
Yassin, M. A., Fuoco, T., Mohamed-Ahmed, S., Mustafa, K. & Finne Wistrand, A. (2019). 3D and Porous RGDC-Functionalized Polyester-Based Scaffolds as a Niche to Induce Osteogenic Differentiation of Human Bone Marrow Stem Cells. Macromolecular Bioscience, 19(6), Article ID 1900049.
Open this publication in new window or tab >>3D and Porous RGDC-Functionalized Polyester-Based Scaffolds as a Niche to Induce Osteogenic Differentiation of Human Bone Marrow Stem Cells
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2019 (English)In: Macromolecular Bioscience, ISSN 1616-5187, E-ISSN 1616-5195, Vol. 19, no 6, article id 1900049Article in journal (Refereed) Published
Abstract [en]

Polyester-based scaffolds covalently functionalized with arginine-glycine-aspartic acid-cysteine (RGDC) peptide sequences support the proliferation and osteogenic differentiation of stem cells. The aim is to create an optimized 3D niche to sustain human bone marrow stem cell (hBMSC) viability and osteogenic commitment, without reliance on differentiation media. Scaffolds consisting of poly(lactide-co-trimethylene carbonate), poly(LA-co-TMC), and functionalized poly(lactide) copolymers with pendant thiol groups are prepared by salt-leaching technique. The availability of functional groups on scaffold surfaces allows for an easy and straightforward method to covalently attach RGDC peptide motifs without affecting the polymerization degree. The strategy enables the chemical binding of bioactive motifs on the surfaces of 3D scaffolds and avoids conventional methods that require harsh conditions. Gene and protein levels and mineral deposition indicate the osteogenic commitment of hBMSC cultured on the RGDC functionalized surfaces. The osteogenic commitment of hBMSC is enhanced on functionalized surfaces compared with nonfunctionalized surfaces and without supplementing media with osteogenic factors. Poly(LA-co-TMC) scaffolds have potential as scaffolds for osteoblast culture and bone grafts. Furthermore, these results contribute to the development of biomimetic materials and allow a deeper comprehension of the importance of RGD peptides on stem cell transition toward osteoblastic lineage.

Place, publisher, year, edition, pages
WILEY-V C H VERLAG GMBH, 2019
Keywords
degradable polymer, human bone marrow stem cells, poly(l-lactide-co-trimethylene carbonate), RGDC
National Category
Polymer Chemistry
Identifiers
urn:nbn:se:kth:diva-255207 (URN)10.1002/mabi.201900049 (DOI)000471782900010 ()31050389 (PubMedID)2-s2.0-85065316726 (Scopus ID)
Note

QC 20190904

Available from: 2019-09-04 Created: 2019-09-04 Last updated: 2019-09-04Bibliographically approved
Pappalardo, D., Mathisen, T. & Finne Wistrand, A. (2019). Biocompatibility of Resorbable Polymers: A Historical Perspective and Framework for the Future. Biomacromolecules, 20(4), 1465-1477
Open this publication in new window or tab >>Biocompatibility of Resorbable Polymers: A Historical Perspective and Framework for the Future
2019 (English)In: Biomacromolecules, ISSN 1525-7797, E-ISSN 1526-4602, Vol. 20, no 4, p. 1465-1477Article in journal (Refereed) Published
Abstract [en]

The history of resorbable polymers containing glycolide, lactide, e-caprolactone and trimethylene carbonate, with a special emphasis being placed on the time frame of the 1960s-1990s is described. Reviewing the history is valuable when looking into the future perspectives regarding how and where these monomers should be used. This story includes scientific evaluations indicating that these polymers are safe to use in medical devices, while the design of the medical device is not considered in this report. In particular, we present the data regarding the tissue response to implanted polymers, as well as the toxicity and pharmacokinetics of their degradation products. In the translation of these polymers from "the bench to the bedside," various challenges have been faced by surgeons, medical doctors, biologists, material engineers and polymer chemists. This Perspective highlights the visionary role played by the pioneers, addressing the problems that occurred on a case by case basis in translational medicine.

Place, publisher, year, edition, pages
AMER CHEMICAL SOC, 2019
Keywords
NDUNNEN WFA, 1993, JOURNAL OF MATERIALS SCIENCE-MATERIALS IN MEDICINE, V4, P521 nmark S., 2011, ACTA BIOMATERIALIA, V7, P2035 go AP, 2003, JOURNAL OF BIOMEDICAL MATERIALS RESEARCH PART A, V67A, P1044, NDUNNEN WFA, 1993, MICROSURGERY, V14, P508 go AP, 2002, MACROMOLECULAR BIOSCIENCE, V2, P411, NDUNNEN WFA, 1995, JOURNAL OF BIOMEDICAL MATERIALS RESEARCH, V29, P757, LGUERRA RS, 1994, JOURNAL OF MATERIALS SCIENCE-MATERIALS IN MEDICINE, V5, P891 e of International Standard., 2016, ISO 109931, ndgren D., 1994, J. Swed. Dent. Assoc, V65, P967
National Category
Polymer Chemistry
Identifiers
urn:nbn:se:kth:diva-251216 (URN)10.1021/acs.biomac.9b00159 (DOI)000464248300001 ()30855137 (PubMedID)2-s2.0-85064110982 (Scopus ID)
Note

QC 20190524

Available from: 2019-05-24 Created: 2019-05-24 Last updated: 2019-05-24Bibliographically approved
Munir, A., Doskeland, A., Avery, S. J., Fuoco, T., Mohamed-Ahmed, S., Lygre, H., . . . Suliman, S. (2019). Efficacy of copolymer scaffolds delivering human demineralised dentine matrix for bone regeneration. Journal of Tissue Engineering, 10, Article ID 2041731419852703.
Open this publication in new window or tab >>Efficacy of copolymer scaffolds delivering human demineralised dentine matrix for bone regeneration
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2019 (English)In: Journal of Tissue Engineering, ISSN 2041-7314, E-ISSN 2041-7314, Vol. 10, article id 2041731419852703Article in journal (Refereed) Published
Abstract [en]

Poly(L-lactide-co-epsilon-caprolactone) scaffolds were functionalised by 10 or 20 mu g/mL of human demineralised dentine matrix. Release kinetics up to 21 days and their osteogenic potential on human bone marrow stromal cells after 7 and 21 days were studied. A total of 390 proteins were identified by mass spectrometry. Bone regeneration proteins showed initial burst of release. Human bone marrow stromal cells were cultured on scaffolds physisorbed with 20 mu g/mL and cultured in basal medium (DDM group) or physisorbed and cultured in osteogenic medium or cultured on non-functionalised scaffolds in osteogenic medium. The human bone marrow stromal cells proliferated less in demineralised dentine matrix group and activated ERK/1/2 after both time points. Cells on DDM group showed highest expression of IL-6 and IL-8 at 7 days and expressed higher collagen type 1 alpha 2, SPP1 and bone morphogenetic protein-2 until 21 days. Extracellular protein revealed higher collagen type 1 and bone morphogenetic protein-2 at 21 days in demineralised dentine matrix group. Cells on DDM group showed signs of mineralisation. The functionalised scaffolds were able to stimulate osteogenic differentiation of human bone marrow stromal cells.

Place, publisher, year, edition, pages
SAGE PUBLICATIONS INC, 2019
Keywords
Growth factor, mesenchymal stem cell, bone tissue engineering, drug delivery, functionalisation
National Category
Cell and Molecular Biology
Identifiers
urn:nbn:se:kth:diva-254028 (URN)10.1177/2041731419852703 (DOI)000469789400001 ()2-s2.0-85066462356 (Scopus ID)
Note

QC 20190814

Available from: 2019-08-14 Created: 2019-08-14 Last updated: 2019-08-14Bibliographically approved
Fuoco, T. & Finne Wistrand, A. (2019). Enhancing the Properties of Poly(epsilon-caprolactone) by Simple and Effective Random Copolymerization of epsilon-Caprolactone with p-Dioxanone. Biomacromolecules, 20(8), 3171-3180
Open this publication in new window or tab >>Enhancing the Properties of Poly(epsilon-caprolactone) by Simple and Effective Random Copolymerization of epsilon-Caprolactone with p-Dioxanone
2019 (English)In: Biomacromolecules, ISSN 1525-7797, E-ISSN 1526-4602, Vol. 20, no 8, p. 3171-3180Article in journal (Refereed) Published
Abstract [en]

We have developed a straightforward strategy to obtain semicrystalline and random copolymers of epsilon-caprolactone (CL) and p-dioxanone (DX) with thermal stabilities similar to poly(epsilon-caprolactone), PCL, but with a faster- hydrolytic degradation rate-CL/DX-copolymers-are promising inks when printing scaffolds aimed for tissue engineering. Such copolymers behave similar to PCL and resorb faster. The copolymers were synthesized by bulk ring-opening copolymerization, achieving a high yield; a molecular weight, M-n, of 57-176 kg mol(-1); and an inherent viscosity of 1.7-1.9 dL g(-1). The copolymer microstructure consisted of long CL blocks that are separated by isolated DX units. The block length and the melting point were a linear function of the DX content. The copolymers crystallize as an orthorhombic lattice that is typical for PCL, and they formed more elastic, softer, and less hydrophobic films with faster degradation rates than PCL. Relatively high thermal degradation temperatures (above 250 C), similar to PCL, were estimated by thermogravimetric analysis, and copolymer filaments for three-dimensional printing and scaffolds were produced without thermal degradation.

Place, publisher, year, edition, pages
AMER CHEMICAL SOC, 2019
National Category
Polymer Chemistry
Identifiers
urn:nbn:se:kth:diva-257817 (URN)10.1021/acs.biomac.9b00745 (DOI)000480826700027 ()31268691 (PubMedID)2-s2.0-85071333322 (Scopus ID)
Note

QC 20190906

Available from: 2019-09-06 Created: 2019-09-06 Last updated: 2019-09-06Bibliographically approved
Fuoco, T., Mathisen, T. & Finne Wistrand, A. (2019). Minimizing the time gap between service lifetime and complete resorption of degradable melt-spun multifilament fibers. Polymer degradation and stability, 163, 43-51
Open this publication in new window or tab >>Minimizing the time gap between service lifetime and complete resorption of degradable melt-spun multifilament fibers
2019 (English)In: Polymer degradation and stability, ISSN 0141-3910, E-ISSN 1873-2321, Vol. 163, p. 43-51Article in journal (Refereed) Published
Abstract [en]

We have succeeded to modulated the degradation rate of poly(L-lactide) (PLLA) melt-spun multifilament fibers to extend the service lifetime and increase the resorption rate by using random copolymers of L-lactide and trimethylene carbonate (TMC). The presence of TMC units enabled an overall longer service lifetime but faster degradation kinetics than PLLA. By increasing the amount of TMC up to 18 mol%, multifilament fibers characterized by a homogenous degradation profile could be achieved. Such composition allowed, once the mechanical integrity was lost, a much longer retention of mechanical integrity and a faster rate of mass loss than samples containing less TMC. The degradation profile of multifilament fibers consisting of (co)polymers containing 0, 5, 10 and 18 mol% of TMC has been identified during 45 weeks in vitro hydrolysis following the molecular weight decrease, mass loss and changes in microstructure, crystallinity and mechanical properties. The fibers degraded by a two-step, autocatalyzed bulk hydrolysis mechanism. A high rate of molecular weight decrease and negligible mass loss, with a consequent drop of the mechanical properties, was observed in the early stage of degradation for fibers having TMC content up to 10 mol%. The later stage of degradation was, for these samples, characterized by a slight increase in the mass loss and a negligible molecular weight decrease. Fibers prepared with the 18 mol% TMC copolymer showed instead a more homogenous molecular weight decrease ensuring mechanical integrity for longer time and faster mass loss during the later stage of degradation.

Place, publisher, year, edition, pages
Elsevier, 2019
Keywords
Bulk degradation, Degradable copolymers, Melt-spun multifilament fibers, Poly(L-lactide-co-trimethylene carbonate), Service lifetime
National Category
Polymer Technologies
Identifiers
urn:nbn:se:kth:diva-246427 (URN)10.1016/j.polymdegradstab.2019.02.026 (DOI)000468250100006 ()2-s2.0-85062444715 (Scopus ID)
Note

QC 20190329

Available from: 2019-03-29 Created: 2019-03-29 Last updated: 2019-10-24Bibliographically approved
Fuoco, T., Mathisen, T. & Finne Wistrand, A. (2019). Poly(L-lactide) and Poly(L-lactide-co-trimethylene carbonate) Melt-Spun Fibers: Structure-Processing-Properties Relationship. Biomacromolecules, 20(3), 1346-1361
Open this publication in new window or tab >>Poly(L-lactide) and Poly(L-lactide-co-trimethylene carbonate) Melt-Spun Fibers: Structure-Processing-Properties Relationship
2019 (English)In: Biomacromolecules, ISSN 1525-7797, E-ISSN 1526-4602, Vol. 20, no 3, p. 1346-1361Article in journal (Refereed) Published
Abstract [en]

l-Lactide/trimethylene carbonate copolymers have been produced as multifilament fibers by high-speed melt-spinning. The relationship existing between the composition, processing parameters and physical properties of the fibers has been disclosed by analyzing how the industrial process induced changes at the macromolecular level, i.e., the chain microstructure and crystallinity development. A poly(l-lactide) and three copolymers having trimethylene carbonate contents of 5, 10 and 18 mol % were synthesized with high molecular weight (M n ) up to 377 kDa and narrow dispersity. Their microstructure, crystallinity and thermal properties were dictated by the composition. The spinnability was then assessed for all the as-polymerized materials: four melt-spun multifilament fibers with increasing linear density were collected for each (co)polymer at a fixed take-up speed of 1800 m min -1 varying the mass throughput during the extrusion. A linear correlation resulted between the as-spun fiber properties and the linear density. The as-spun fibers could be further oriented, developing more crystallinity and improving their tensile properties by a second stage of hot-drawing. This ability was dependent on the composition and crystallinity achieved during the melt-spinning and the parameters selected for the hot-drawing, such as temperature, draw ratio and input speed. The crystalline structure evolved to a more stable form, and the degree of crystallinity increased from 0-52% to 25-66%. Values of tensile strength and Young's modulus up to 0.32-0.61 GPa and 4.9-8.4 GPa were respectively achieved.

Place, publisher, year, edition, pages
AMER CHEMICAL SOC, 2019
National Category
Polymer Chemistry
Identifiers
urn:nbn:se:kth:diva-248094 (URN)10.1021/acs.biomac.8b01739 (DOI)000461270500022 ()30665299 (PubMedID)2-s2.0-85061266532 (Scopus ID)
Note

QC 20190429

Available from: 2019-04-29 Created: 2019-04-29 Last updated: 2019-05-20Bibliographically approved
Jain, S., Fuoco, T., Yassin, M. A., Mustafa, K. & Finne Wistrand, A. (2019). Printability and critical insight into polymer properties during direct- extrusion based 3D printing of medical grade polylactide and copolyesters. Biomacromolecules
Open this publication in new window or tab >>Printability and critical insight into polymer properties during direct- extrusion based 3D printing of medical grade polylactide and copolyesters
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2019 (English)In: BiomacromoleculesArticle in journal (Refereed) Published
Abstract [en]

Various 3D printing techniques currently usedegradable polymers such as aliphatic polyesters to create welldefinedscaffolds. Even though degradable polymers are influencedby the printing process, and this subsequently affects themechanical properties and degradation profile, degradation of thepolymer during the process is not often considered. Degradablescaffolds are today printed and cell−material interactions evaluatedwithout considering the fact that the polymer change while printingthe scaffold. Our methodology herein was to vary the printingparameters such as temperature, pressure, and speed to define therelationship between printability, polymer microstructure, composition,degradation profile during the process, and rheologicalbehavior. We used high molecular weight medical-grade (co)polymers, poly(L-lactide-co-ε-caprolactone) (PCLA), poly(Llactide-co-glycolide) (PLGA), and poly(D,L-lactide-co-glycolide) (PDLGA), with L-lactide content ranging from 25 to 100 mol%, for printing in an extrusion-based printer (3D Bioplotter). Optical microscopy confirmed that the polymers were printable athigh resolution and good speed, until a certain degree of degradation. The results show also that printability can not be claimedjust by optimizing printing parameters and highlight the importance of a careful analysis of how the polymer’s structure andproperties vary during printing. The polymers thermally decomposed from the first processing minute and caused a decrease inthe average block length of the lactide blocks in the copolymers and generated lower crystallinity. Poly(L-lactide) (PLLA) andPCLA are printable at a higher molecular weight, less degradation before printing was possible, compared to PLGA andPDLGA, a result explained by the higher complex viscosity and more elastic polymeric melt of the copolymer containingglycolide (GA) and lactide (LA). In more detail, copolymers comprised of LA and ε-caprolactone (CL) formed lower molecularweight compounds over the course of printing, while the PLGA copolymer was more susceptible to intermoleculartransesterification reactions, which do not affect the overall molecular weight, but cause changes in the copolymermicrostructure. This results in a longer printing time for PLGA than PLLA and PCLA

National Category
Polymer Chemistry
Identifiers
urn:nbn:se:kth:diva-268326 (URN)10.1021/acs.biomac.9b01112 (DOI)2-s2.0-85073450017 (Scopus ID)
Note

QC 20200310

Available from: 2020-03-10 Created: 2020-03-10 Last updated: 2020-03-10Bibliographically approved
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Identifiers
ORCID iD: ORCID iD iconorcid.org/0000-0002-1922-128X

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