Aim:

To study the effect of NaOH concentration and duration of treatment on the % mass loss of 19 wt% uncalcined carbonated hydroxyapatite (CHA)/Poly- ε -caprolactone (PCL)

To analyze the degradation behaviour of composites and to evaluate the possibility of bone replacement by the study of buffer saline solution (PBS) following NaOH application.

Material and Method:

CHA was produced using a wet precipitation method. The CHA/PCL composites were prepared by twin screw extrusion followed by injection moulding. In order to accelerate the degradation rate of 19 wt% uncalcinated CHA/PCL, the samples were surface treated with various concentrations of NaOH (Sigma Aldrich, UK) for various durations. Biological degradation rates were analyzed in PBS

Results:

The increase of the concentration of NaOH from 3 M to 5 M increased the % weight loss of the samples after NaOH treatment and subsequent PBS studies. However, increasing the durahon of surface treatment from one day to three days in 5 M NaOH did not affect the % weight change.

Conclusions:

Biological degradation rate was accelerated with the increase of NaOH concentration. 19 wt% uncalcined CHA/PCL samples that were surface treated with 3 M NaOH for one day had a more controlled degradation during subsequent PBS studies

Keywords: Poly- ε -caprolactone, carbonated hydroxyapatite, NaOH treatment, biological degradation study, twin screw extrusion, injection moulding