Avoiding artefacts in MicroCT imaging of collagen scaffolds: Effect of phosphotungstic acid (PTA)-staining and crosslink density

X-ray micro-computed tomography (μ-CT) can be used to provide both qualitative and quantitative information on the structure of three-dimensional (3D) bioactive scaffolds. When performed in a dry state, μ-CT accurately reflects the structure of collagen-based scaffolds, but imaging in a wet state of...

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Main Authors: Kyung-Ah Kwon, Daniel V. Bax, Jennifer H. Shepherd, Ruth E. Cameron, Serena M. Best
Format: Article
Language:English
Published: KeAi Communications Co., Ltd. 2022-02-01
Series:Bioactive Materials
Online Access:http://www.sciencedirect.com/science/article/pii/S2452199X2100298X
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author Kyung-Ah Kwon
Daniel V. Bax
Jennifer H. Shepherd
Ruth E. Cameron
Serena M. Best
author_facet Kyung-Ah Kwon
Daniel V. Bax
Jennifer H. Shepherd
Ruth E. Cameron
Serena M. Best
author_sort Kyung-Ah Kwon
collection DOAJ
description X-ray micro-computed tomography (μ-CT) can be used to provide both qualitative and quantitative information on the structure of three-dimensional (3D) bioactive scaffolds. When performed in a dry state, μ-CT accurately reflects the structure of collagen-based scaffolds, but imaging in a wet state offers challenges with radiolucency. Here we have used phosphotungstic acid (PTA) as a contrast agent to visualise fully hydrated collagen scaffolds in a physiologically relevant environment. A systematic investigation was performed to understand the effects of PTA on the results of μ-CT imaging by varying sample processing variables such as crosslinking density, hydration medium and staining duration.Immersing samples in 0.3% PTA solution overnight completely stained the samples and the treatment provided a successful route for μ-CT analysis of crosslinked samples. However, significant structural artefacts were observed for samples which were either non-crosslinked or had low levels of crosslinking, which had a heterogeneous interior architecture with collapsed pores at the scaffold periphery. This work highlights the importance of optimising the choice of processing and staining conditions to ensure accurate visualisation for hydrated 3D collagen scaffolds in an aqueous medium.
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spelling doaj.art-56a137cec150474b81baacf6e7145fea2024-04-16T18:48:13ZengKeAi Communications Co., Ltd.Bioactive Materials2452-199X2022-02-018210219Avoiding artefacts in MicroCT imaging of collagen scaffolds: Effect of phosphotungstic acid (PTA)-staining and crosslink densityKyung-Ah Kwon0Daniel V. Bax1Jennifer H. Shepherd2Ruth E. Cameron3Serena M. Best4Cambridge Centre for Medical Materials, Department of Materials Science and Metallurgy, University of Cambridge, Cambridge, United Kingdom; Corresponding author.Cambridge Centre for Medical Materials, Department of Materials Science and Metallurgy, University of Cambridge, Cambridge, United KingdomSchool of Engineering, University of Leicester, Leicester, United KingdomCambridge Centre for Medical Materials, Department of Materials Science and Metallurgy, University of Cambridge, Cambridge, United KingdomCambridge Centre for Medical Materials, Department of Materials Science and Metallurgy, University of Cambridge, Cambridge, United KingdomX-ray micro-computed tomography (μ-CT) can be used to provide both qualitative and quantitative information on the structure of three-dimensional (3D) bioactive scaffolds. When performed in a dry state, μ-CT accurately reflects the structure of collagen-based scaffolds, but imaging in a wet state offers challenges with radiolucency. Here we have used phosphotungstic acid (PTA) as a contrast agent to visualise fully hydrated collagen scaffolds in a physiologically relevant environment. A systematic investigation was performed to understand the effects of PTA on the results of μ-CT imaging by varying sample processing variables such as crosslinking density, hydration medium and staining duration.Immersing samples in 0.3% PTA solution overnight completely stained the samples and the treatment provided a successful route for μ-CT analysis of crosslinked samples. However, significant structural artefacts were observed for samples which were either non-crosslinked or had low levels of crosslinking, which had a heterogeneous interior architecture with collapsed pores at the scaffold periphery. This work highlights the importance of optimising the choice of processing and staining conditions to ensure accurate visualisation for hydrated 3D collagen scaffolds in an aqueous medium.http://www.sciencedirect.com/science/article/pii/S2452199X2100298X
spellingShingle Kyung-Ah Kwon
Daniel V. Bax
Jennifer H. Shepherd
Ruth E. Cameron
Serena M. Best
Avoiding artefacts in MicroCT imaging of collagen scaffolds: Effect of phosphotungstic acid (PTA)-staining and crosslink density
Bioactive Materials
title Avoiding artefacts in MicroCT imaging of collagen scaffolds: Effect of phosphotungstic acid (PTA)-staining and crosslink density
title_full Avoiding artefacts in MicroCT imaging of collagen scaffolds: Effect of phosphotungstic acid (PTA)-staining and crosslink density
title_fullStr Avoiding artefacts in MicroCT imaging of collagen scaffolds: Effect of phosphotungstic acid (PTA)-staining and crosslink density
title_full_unstemmed Avoiding artefacts in MicroCT imaging of collagen scaffolds: Effect of phosphotungstic acid (PTA)-staining and crosslink density
title_short Avoiding artefacts in MicroCT imaging of collagen scaffolds: Effect of phosphotungstic acid (PTA)-staining and crosslink density
title_sort avoiding artefacts in microct imaging of collagen scaffolds effect of phosphotungstic acid pta staining and crosslink density
url http://www.sciencedirect.com/science/article/pii/S2452199X2100298X
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