Process-Induced Degradation of Bioresorbable PDLGA in Bone Tissue Scaffold Production

Research output: Contribution to journalArticle

2 Citations (Scopus)
21 Downloads (Pure)

Abstract

Process-induced degradation of clinically relevant resorbable polymers was investigated for two thermal techniques, filament extrusion followed by fused deposition modelling (FDM). The aim was to develop a clear understanding of the relationship between temperature, processing time and resultant process-induced degradation. This acts to address the current knowledge gap in studies involving thermal processing of resorbable polymers. Poly(DL-lactide-co-glycolide) (PDLGA) was chosen for its clinically relevant resorption properties. Furthermore, a comparative study of controlled thermal exposure was conducted through compression moulding PDLGA at a selected range of temperatures (150–225 °C) and times (0.5–20 min). Differential scanning calorimetry (DSC) and gel permeation chromatography (GPC) were used to characterise thermally induced degradation behaviour. DSC proved insensitive to degradation effects, whereas GPC demonstrated distinct reductions in molecular weight allowing for the quantification of degradation. A near-exponential pattern of degradation was identified. Through the application of statistical chain scission equations, a predictive plot of theoretical degradation was created. Thermal degradation was found to have a significant effect on the molecular weight with a reduction of up to 96% experienced in the controlled processing study. The proposed empirical model may assist prediction of changes in molecular weight, however, accuracy limitations are highlighted for twin-screw extrusion, accredited to high-shear mixing. The results from this study highlight the process sensitivity of PDLGA and proposes a methodology for quantification and prediction, which contributes to efforts in understanding the influence of manufacture on performance of degradable medical implants.
Original languageEnglish
Article number14
Number of pages10
JournalJournal of Materials Science: Materials in Medicine
Volume29
Early online date28 Dec 2017
DOIs
Publication statusPublished - Jan 2018

Fingerprint

Tissue Scaffolds
Bone
Hot Temperature
Bone and Bones
Degradation
Molecular Weight
Differential Scanning Calorimetry
Gel Chromatography
Polymers
Polyglactin 910
Molecular weight
Gel permeation chromatography
Temperature
Extrusion
Differential scanning calorimetry
Compression molding
Processing
Pyrolysis

Cite this

@article{6626522ef4b040d8b30e2346fe6e48be,
title = "Process-Induced Degradation of Bioresorbable PDLGA in Bone Tissue Scaffold Production",
abstract = "Process-induced degradation of clinically relevant resorbable polymers was investigated for two thermal techniques, filament extrusion followed by fused deposition modelling (FDM). The aim was to develop a clear understanding of the relationship between temperature, processing time and resultant process-induced degradation. This acts to address the current knowledge gap in studies involving thermal processing of resorbable polymers. Poly(DL-lactide-co-glycolide) (PDLGA) was chosen for its clinically relevant resorption properties. Furthermore, a comparative study of controlled thermal exposure was conducted through compression moulding PDLGA at a selected range of temperatures (150–225 °C) and times (0.5–20 min). Differential scanning calorimetry (DSC) and gel permeation chromatography (GPC) were used to characterise thermally induced degradation behaviour. DSC proved insensitive to degradation effects, whereas GPC demonstrated distinct reductions in molecular weight allowing for the quantification of degradation. A near-exponential pattern of degradation was identified. Through the application of statistical chain scission equations, a predictive plot of theoretical degradation was created. Thermal degradation was found to have a significant effect on the molecular weight with a reduction of up to 96{\%} experienced in the controlled processing study. The proposed empirical model may assist prediction of changes in molecular weight, however, accuracy limitations are highlighted for twin-screw extrusion, accredited to high-shear mixing. The results from this study highlight the process sensitivity of PDLGA and proposes a methodology for quantification and prediction, which contributes to efforts in understanding the influence of manufacture on performance of degradable medical implants.",
author = "H. Little and Efrosyni Themistou and Clarke, {S. A.} and E. Cunningham and F. Buchanan",
year = "2018",
month = "1",
doi = "10.1007/s10856-018-6035-7",
language = "English",
volume = "29",
journal = "Journal of Materials Science: Materials in Medicine",
issn = "0957-4530",
publisher = "Springer Netherlands",

}

TY - JOUR

T1 - Process-Induced Degradation of Bioresorbable PDLGA in Bone Tissue Scaffold Production

AU - Little, H.

AU - Themistou, Efrosyni

AU - Clarke, S. A.

AU - Cunningham, E.

AU - Buchanan, F.

PY - 2018/1

Y1 - 2018/1

N2 - Process-induced degradation of clinically relevant resorbable polymers was investigated for two thermal techniques, filament extrusion followed by fused deposition modelling (FDM). The aim was to develop a clear understanding of the relationship between temperature, processing time and resultant process-induced degradation. This acts to address the current knowledge gap in studies involving thermal processing of resorbable polymers. Poly(DL-lactide-co-glycolide) (PDLGA) was chosen for its clinically relevant resorption properties. Furthermore, a comparative study of controlled thermal exposure was conducted through compression moulding PDLGA at a selected range of temperatures (150–225 °C) and times (0.5–20 min). Differential scanning calorimetry (DSC) and gel permeation chromatography (GPC) were used to characterise thermally induced degradation behaviour. DSC proved insensitive to degradation effects, whereas GPC demonstrated distinct reductions in molecular weight allowing for the quantification of degradation. A near-exponential pattern of degradation was identified. Through the application of statistical chain scission equations, a predictive plot of theoretical degradation was created. Thermal degradation was found to have a significant effect on the molecular weight with a reduction of up to 96% experienced in the controlled processing study. The proposed empirical model may assist prediction of changes in molecular weight, however, accuracy limitations are highlighted for twin-screw extrusion, accredited to high-shear mixing. The results from this study highlight the process sensitivity of PDLGA and proposes a methodology for quantification and prediction, which contributes to efforts in understanding the influence of manufacture on performance of degradable medical implants.

AB - Process-induced degradation of clinically relevant resorbable polymers was investigated for two thermal techniques, filament extrusion followed by fused deposition modelling (FDM). The aim was to develop a clear understanding of the relationship between temperature, processing time and resultant process-induced degradation. This acts to address the current knowledge gap in studies involving thermal processing of resorbable polymers. Poly(DL-lactide-co-glycolide) (PDLGA) was chosen for its clinically relevant resorption properties. Furthermore, a comparative study of controlled thermal exposure was conducted through compression moulding PDLGA at a selected range of temperatures (150–225 °C) and times (0.5–20 min). Differential scanning calorimetry (DSC) and gel permeation chromatography (GPC) were used to characterise thermally induced degradation behaviour. DSC proved insensitive to degradation effects, whereas GPC demonstrated distinct reductions in molecular weight allowing for the quantification of degradation. A near-exponential pattern of degradation was identified. Through the application of statistical chain scission equations, a predictive plot of theoretical degradation was created. Thermal degradation was found to have a significant effect on the molecular weight with a reduction of up to 96% experienced in the controlled processing study. The proposed empirical model may assist prediction of changes in molecular weight, however, accuracy limitations are highlighted for twin-screw extrusion, accredited to high-shear mixing. The results from this study highlight the process sensitivity of PDLGA and proposes a methodology for quantification and prediction, which contributes to efforts in understanding the influence of manufacture on performance of degradable medical implants.

U2 - 10.1007/s10856-018-6035-7

DO - 10.1007/s10856-018-6035-7

M3 - Article

VL - 29

JO - Journal of Materials Science: Materials in Medicine

JF - Journal of Materials Science: Materials in Medicine

SN - 0957-4530

M1 - 14

ER -