Chitosan /gum arabic nanoparticles (C/G)have been prepared by ionic gelation method. This was with a view to enhance the mechanical properties and its application as bone graft scaffold. The cowry shells were washed, dried, pulverized and subsequently sieved with mesh No. 60, size 250 µm. It was deproteinized, Chitin was isolated from the synthesis by demineralising in 0.5 M Hydrochloric acid, and subsequently deacetylated by the addition of 40% (W/V) of Sodium hydroxide to synthesize chitosan. The raw chitosan was purified using 2% (v/v) acetic acid solution. The synthesized chitosan and gum arabic, a product of Acacia tree, were used to prepare chitosan/gum arabic nanoparticles by ionic gelation method. Mechanical characterization was carried out on the synthesized material using universal testing machine. Analysis of the chemical composition was carried out using Fourier transform infrared spectrometer (FTIR) and X-Ray fluorescence, (XRF). Furthermore, the morphology of the materials were studied using scanning electron microscopy, SEM and the dimension of the nanoparticles were characterized using transmission electron microscopy (TEM). Finally, an attempt was made to ascertain its suitability for bone regeneration. The FTIR spectra result confirmed that the nanoparticle was actually a derivative of chitosan by the observed shift in the peak 3462 to 3404cm- -1 and 712 cm -1 on C/G nanoparticles spectrum were similar to the native chitosan spectrum which shows that there was no change in the main backbone of chitosan structure. The scanning electron microscopy (SEM) study revealed chitosan as polymeric rods, while the chitosan /gum arabic nanoparticles in aggregate. The TEM was to confirm nanoparticles of average size of 200nm. The ultimate compressive strength was found to have increased by 78.21%, the Young Modulus by 54.4 % and percentage elongation by 7%. In overall assessment, mechanical properties of the chitosan/gum arabic nanoparticles were better than native chitosan. The study concluded that crosslinking of chitosan with gum arabic to form its nanoparticles derivative improved the mechanical properties of chitosan and consequently its application as a bone graft substitute for bone regeneration.

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The granite formation for production of dimension stone blocks at Utan was investigated in three different locations A, B and C in a view to examine the physical properties of Utan granite using saturation and Buoyancy technique; evaluate some of its mechanical properties; determine its rate of emission of radioactive elements with Geiger Muller Counter; examine its polish-ability; and carry out chemical analysis of the granite samples with the aid of energy dispersive x-ray florescence (ED-XRF). The average porosity obtained is 0.53, 1.08; and 0.86 while the respective average density of 2.58, 2.62 and 2. Mrem respectively. Sample B is observed to be more radioactive. Both samples are polish able. Conclusively, the three tested granite rocks have suitable physical and mechanical properties that meant the requirement for building purposes; from the polish-ability test, it shows that the three (3) granite outcrops are suitable for the production of granite tiles; countertops; slabs. The chemical analysis revealed that the granite is dominated by quartz (SiO 2 ) which contributes greatly to the hardness of the rock. Also from the radioactive test, the granite samples proved conclusively that the rate of radiation found occasionally in a slab of granite is not harmful to humans when exposed to it. Hence, granite the formation of Utan will be a good building stone material.

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