Absorption and release of protein from hydroxyapatite-polylactic acid (HA-PLA) membranes

Talal, A.; Waheed, N.; Al-Masri, M.; McKay, I.J.; Tanner, K.E.; Hughes, F.J.

doi:10.1016/j.jdent.2009.06.014

« Previous Next »Journal of Dentistry
Volume 37, Issue 11 , Pages 820-826, November 2009

Absorption and release of protein from hydroxyapatite-polylactic acid (HA-PLA) membranes

A. Talal
- Department of Materials, Queen Mary University of London, Mile End Road, London E1 4NS, UK
- Corresponding author. Present address: Department of Mechanical Engineering, James Watt South Building, University of Glasgow, Glasgow G12 8QQ, UK. Tel.: +44 141 330 1807; fax: +44 141 330 4343.
N. Waheed
- Department of Materials, Queen Mary University of London, Mile End Road, London E1 4NS, UK
M. Al-Masri
- Centre for Adult Oral Health, Barts and The London School of Medicine and Dentistry, Queen Mary University of London, Turner Street, London E1 2AD, UK
I.J. McKay
- Centre for Adult Oral Health, Barts and The London School of Medicine and Dentistry, Queen Mary University of London, Turner Street, London E1 2AD, UK
K.E. Tanner
- Department of Materials, Queen Mary University of London, Mile End Road, London E1 4NS, UK
- Present address: Departments of Mechanical and Civil Engineering, University of Glasgow, Glasgow, Glasgow G12 8QQ, UK.
F.J. Hughes
- Centre for Adult Oral Health, Barts and The London School of Medicine and Dentistry, Queen Mary University of London, Turner Street, London E1 2AD, UK

Received 8 November 2008; received in revised form 14 June 2009; accepted 19 June 2009. published online 29 June 2009.

Abstract

Objectives

The aim of this study was to investigate the kinetics of protein interactions with a novel hydroxyapatite-polylactide (HA-PLA) composite membrane material.

Methods

Trilayer PLA and HA-PLA composite membranes reinforced with PLA fibres were used to absorb and release protein which was measured by a BioRad assay. The proteins used were fetal calf serum and bovine serum albumin. PLA and HA-PLA composite films were manufactured to test permeability.

Results

Maximal protein absorption was seen within 5min of treating materials; a nearly 8-fold increase in total absorption was seen with HA-containing composites compared to those without HA. These also exhibited a more gradual and sustained release of protein for periods of up to 96h, for example at 24h protein concentrations released were 2.20±2.80 and 0.49±5.38μg/ml for membranes with and without HA respectively. In addition low pressure and temperature used during production of membranes also allowed greater and more sustained protein release. HA-PLA composite films also showed marked increased permeability compared to plain PLA films, for example after 24h PLA only films 3.64±1.01μg/ml, PLA film with 25% HA: 44.99±35.61μg/ml, PLA film with 75% HA: 153.12±65.57μg/ml.

Conclusions

The results demonstrate that these composite membranes rapidly absorb protein and that the absorbed protein is released slowly for periods of up to 96h, dependent on constituents of the material and the manufacturing conditions. Incorporation of HA into these membranes was the key factor for improved protein kinetics and membrane permeability.

Keywords: Polylactic acid, Hydroxyapatite, Protein release, Permeability