The Science & Technology
of Glass
Cambridge - Monday 4th to
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Neelam Iqbal
<pm15ni@leeds.ac.uk>

article posted 02 August 2017


Neelam Iqbal is a Ph.D. student at the University of Leeds, she completed her BEng Medical Engineering degree in 2015 at the University of Bradford and went on to complete an MSc in Materials Science and Engineering in 2016 at the University of Leeds. Her research interests are mainly in tissue engineering, materials science and rehabilitation engineering.

Antonios D Anastasiou is a Marie Curie Fellow in University of Leeds and his research is focused on the development of new ceramic biomaterials for periodontal treatment with the use of femtosecond LASERS.

Mostafa El-Raif gained a degree in Biochemistry, Cell Biology and Genetics in 1990 and completed his PhD in 1993 at the University of Bordeaux, France. He is currently Tissue Culture Facilities Manager in the Department of Oral Biology, University of Leeds School of Dentistry.

Animesh Jha is a professor of Materials Science at the University of Leeds with interest in nanotechnology, integrated photonic devices for micro-lasers, amplifiers and sensors, osteogenic materials for bone restoration, laser surgical procedures for bone and tooth minerals, rare-earth minerals and materials and their applications


Bioglass-Brushite Membranes for Biodegradable Microfluidics
Neelam Iqbal1*, Antonios D Anastasiou1, Mostafa El-Raif2, Animesh Jha1


The fabrication of suitable scaffolds with improved osteogenic and angiogenic properties is one of the greatest challenges in tissue engineering. Particularly for achieving vascularisation, many strategies have been proposed so far but without any significant success. One promising solution for enhancing the formation of new blood vessels is the use of biodegradable microfluidic networks [1]. The micro-channels would support better cell proliferation aiding in enhanced attachment between implants and biological material while the enhanced capillary forces will allow for the circulation of the nutritional components which are necessary for the growth of cells. During last decade an influx of biodegradable polymeric materials have been studied as potential scaffolding materials including polymers such as poly(lactic acid) (PLA), poly(glycolic acid) (PGA), (PGS) and also poly(lactic-co-glycolic acid) (PLGA) [2]. However, for the development of strong and flexible microfluidic networks, these materials lack the mechanical strength (PLGA) and also do not exhibit long half-lives (e.g in PGS) thus degrade too quickly. In order to address this issue, materials which are engineered for tissue and bone replacement must have tuneable properties in order to meet the biological and structural demands for the restoration of a functional tissue as it is bone.

In this work we are investigating chitosan a biocompatible, natural polymer for the fabrication of biodegradable microfluidic medical devices. To improve the mechanical properties of the membranes and to enhance cell attachment and proliferation we used brushite crystals and bioglass microspheres as fillers. Brushite, is a biocompatible mineral with well-known osteoconductive properties while, bioglass is able to interact with both bone and living tissue thus enabling strong apatite bonds to be formed between the scaffold and the bone interface. For the fabrication of the microchannels and the various patterns on the surface of the membranes (fig.1) a femtosecond pulsed laser (1 kHz repetition rate), with peak emission at 800 nm was utilised. Characterisation techniques such as X-Ray diffraction, scanning electron microscopy (SEM), Fourier transform and infrared spectroscopy (FTIR) were employed for comparing and characterising the various concentrations of bioglass-chitosan and brushite-chitosan membranes. Furthermore the rate of degradation and also the swelling index were also established for these materials, as it is an essential characteristic of the chitosan/bioglass materials in membrane form when subjected to wet environments. The degradation results for the brushite-chitosan membranes were promising as indicated by stable weight loss over a 4 week period, hence demonstrating slow degradation in vitro [3].



Fig. 1 Chitosan-brushite membrane with micro-channels (a) untreated chitosan-brushite (b) close up of micro-channel

Reference:

1 Boccaccini, A.R., et al., Polymer/bioactive glass nanocomposites for biomedical applications: A review. Composites Science and Technology, 2010. 70(13): p. 1764-76.
2 Chen, Q.Z., I.D. Thompson, and A.R. Boccaccini, 45S5 Bioglass®-derived glass-ceramic scaffolds for bone tissue engineering. Biomaterials, 2006. 27(11): p. 2414-2425.
3 Iqbal, N., Chitosan Membranes as Constructing Material for Biodegradable Microfluidic Devices, in School of Chemical and Processing Engineering2016, Leeds University Leeds University p. 98.

Institutions:

1 School of Chemical and Process Engineering, University of Leeds, UK
2 Department of Oral Biology, Leeds Dental School, University of Leeds, UK