Research Article
Evaluation of Sterilisation Techniques for Regenerative
Medicine Scaffolds Fabricated with Polyurethane
Nonbiodegradable and Bioabsorbable Nanocomposite Materials
Michelle Griffin ,
1,2,3
Naghmeh Naderi,
1,3,4,5
Deepak M. Kalaskar,
1
Edward Malins,
6
Remzi Becer,
6
Catherine A. Thornton,
4
Iain S. Whitaker,
4,5
Ash Mosahebi,
3
Peter E. M. Butler,
1,2,3
and Alexander M. Seifalian
7
1
UCL Centre for Nanotechnology & Regenerative Medicine, University College London, Royal Free London NHS Foundation Trust,
Pond Street, London NW3 2QG, UK
2
Te Charles Wolfson Center for Reconstructive Surgery, Royal Free London NHS Foundation Trust Hospital, London, UK
3
Department of Plastic Surgery, Royal Free London NHS Foundation Trust, Pond Street, London NW3 2QG, UK
4
Reconstructive Surgery & Regenerative Medicine Group, Institute of Life Science, Swansea University Medical School, Singleton Park,
Swansea SA2 8PP, UK
5
Welsh Centre for Burns & Plastic Surgery, ABMU Health Board, Heol Maes Egwlys, Swansea SA6 6NL, UK
6
Polymer Chemistry Laboratory, School of Engineering and Materials Science, Queen Mary University of London, Mile End Road,
London E1 4NS, UK
7
Director/Professor Nanotechnology & Regenerative Medicine, NanoRegMed Ltd., Te London BioScience Innovation Centre,
London NW1 0NH, UK
Correspondence should be addressed to Michelle Grifn; 12michellegrifn@gmail.com
Received 13 March 2018; Revised 18 June 2018; Accepted 9 August 2018; Published 3 October 2018
Academic Editor: Rosalind Labow
Copyright © 2018 Michelle Grifn et al. Tis is an open access article distributed under the Creative Commons Attribution License,
which permits unrestricted use, distribution, and reproduction in any medium, provided the original work is properly cited.
An efective sterilisation technique that maintains structure integrity, mechanical properties, and biocompatibility is essential for the
translation of new biomaterials to the clinical setting. We aimed to establish an efective sterilisation technique for a biodegradable
(POSS-PCL) and nonbiodegradable (POSS-PCU) nanocomposite scafold that maintains stem cell biocompatibility. Scafolds were
sterilised using 70% ethanol, ultraviolet radiation, bleach, antibiotic/antimycotic, ethylene oxide, gamma irradiation, argon plasma,
or autoclaving. Samples were immersed in tryptone soya broth and thioglycollate medium and inspected for signs of microbial
growth. Scafold surface and mechanical and molecular weight properties were investigated. AlamarBlue viability assay of adipose
derived stem cells (ADSC) seeded on scafolds was performed to investigate metabolic activity. Confocal imaging of rhodamine
phalloidin and DAPI stained ADSCs was performed to evaluate morphology. Ethylene oxide, gamma irradiation, argon plasma,
autoclaving, 70% ethanol, and bleach were efective in sterilising the scafolds. Autoclaving, gamma irradiation, and ethylene oxide
led to a signifcant change in the molecular weight distribution of POSS-PCL and gamma irradiation and ethylene oxide to that of
POSS-PCU (p<0.05). UV, ethanol, gamma irradiation, and ethylene oxide caused signifcant changes in the mechanical properties
of POSS-PCL (p<0.05). Argon was associated with signifcantly higher surface wettability and ADSC metabolic activity (p<0.05).
In this study, argon plasma was an efective sterilisation technique for both nonbiodegradable and biodegradable nanocomposite
scafolds. Argon plasma should be further investigated as a potential sterilisation technique for medical devices.
1. Introduction
Synthetic biomaterials are being used to replace the extracel-
lular matrix to restore damaged and failing tissues and organs
[1]. Amongst biomaterials, polymeric scafolds have gained
signifcant popularity due to their ease of fabrication and
versatility [1]. Polymeric scafolds for tissue engineering are
either manufactured aseptically or sterilised afer processing
Hindawi
International Journal of Biomaterials
Volume 2018, Article ID 6565783, 14 pages
https://doi.org/10.1155/2018/6565783