Abstract:
In this research work (70/30) nanocomposites of Chitosan (CS) biopolymer and
Hydroxyapatite (HA) ceramic powder were synthesized by insitu co-precipitation technique
at different reflux temperatures, combined with double step stirring.
Initially medical grade chitosan was extracted in the laboratory using locally available shrimp
species known as Penaeus Monodon. Extraction of chitosan involved four main stages as
preconditioning, demineralization, deprotenisation and deacetylation. Further purifications
and modifications were done on extracted chitosan to obtain medical grade chitosan.
To synthesize the nanocomposite, analytical grade acetic acid, H3PO4 and Ca(OH)2
used as starting materials. At first, chitosan was dissolved in acetic acid and mixed with
required amount of H3PO4 acid. Then the chitosan / H3PO4 solution was added drop wise into
the highly alkaline Ca(OH)2 suspension. During the addition chitosan precipitated with
hydroxyapatite by forming the chitosan/ hydroxyapatite composite. The precipitate was
filtered and washed with distilled water. Then the precipitate was subsequently compressed
into a cylindrical form under a uniaxial pressure.
Synthesized composite was characterized using Fourier Transform Infrared Spectroscopy
(FTIR), X-ray diffraction (XRD), thermogravimetric analysis (TGA), scanning electron
microscopy (SEM) and differential thermal analysis (DTA). The XRD spectrum
demonstrated relevance peaks of chitosan and HA in composite. FTIR spectrum of composite
showed the characteristics bond energies of chitosan sample and hydroxyapatite sample.
SEM images demonstrated a uniform hydroxyapatite particle distribution in the Chitosan
matrix. Each characterization techniques confirm the existence of chitosan and HA in the
composite. The size of the HA crystals embedded in composite was calculated using Scherrer
formula and it was found to be ~80nm to 100 nm. The basic materials properties of the
composite are compatible with the properties of biomaterials that are intended to be used in
tissue engineering applications.
Therefore, it can be concluded that (70/30) nanocomposites of Chitosan biopolymer and
Hydroxyapatite ceramic powder of nano size particles have been successfully synthesized
with required material properties
