Carbonate apatite (CO Ap) blocks have attracted considerable attention as an artificial bone substitute material because CO Ap is a component of and shares properties with bone, including high osteoconductivity and replacement by bone similar to autografts. In this study, we fabricated an interconnected porous CO Ap block using α-tricalcium phosphate (TCP) spheres and evaluated the tissue response to this material in a rabbit tibial bone defect model. Interconnected porous α-TCP, the precursor of interconnected porous CO Ap, could not be fabricated directly by sintering α-TCP spheres. It was therefore made via a setting reaction with α-TCP spheres, yielding interconnected porous calcium-deficient hydroxyapatite that was subjected to heat treatment. Immersing the interconnected porous α-TCP in Na-CO -PO solution produced CO Ap, which retained the interconnected porous structure after the dissolution-precipitation reaction. The diametral tensile strength and porosity of the porous CO Ap were 1.8 ± 0.4 MPa and 55% ± 3.2%, respectively. Both porous and dense (control) CO Ap showed excellent tissue response and good osteoconductivity. At 4 weeks after surgery, approximately 15% ± 4.9% of the tibial bone defect was filled with new bone when reconstruction was performed using porous CO Ap; this amount was five times greater than that obtained with dense CO Ap. At 12 weeks after surgery, for porous CO Ap, approximately 47% of the defect was filled with new bone as compared to 16% for dense CO Ap. Thus, the interconnected porous CO Ap block is a promising artificial bone substitute material for the treatment of bone defects caused by large fractures or bone tumor resection. © 2018 Wiley Periodicals, Inc. J Biomed Mater Res Part B: Appl Biomater, 2018.

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Pine trees in Indonesia are largely of the pine mercusii species which typically give turpentine that contains about 82% α-pinene, 12% carene and is balanced with numerous other components such as camphene, β-pinene and limonene. When treated with water in the presence of an acetic acid catalyst, α-pinene is hydrated to become a complex mixture of monoterpenes, alcohol and hydrocarbons, although α-terpineol predominates. This α-terpineol is a valuable compound which is widely used as a fragrant substance in the cosmetic industry as an anti fungal agent in the pharmaceutical industry, a disinfectant, an odorant in the cleaning industry and as a mineral flotation agent in the mining industry. A conventional configuration for this hydration process involves two steps, chemical reaction of α-pinene in a reactor followed by a separation step in a distillation column. In this experiment, we combined both chemical reactions and separation by distillation in a reactive distillation column to reduce the production and operating cost. Steady state condition, feed plate position, pressure and volumetric ratio of α-pinene and CAA solution were investigated to study the effect of using this method. A certain ratio of 87% weight of α-pinene and 5.3 M Choloroacetic Acid (CAA) solution as a catalyst were inputted to the reactive distillation column. The result shows that the highest purity of α-terpineol is 38.89 % weight.

The aim of present study was to fabricate porous a-tricalcium phosphate (a-TCP) with adequate mechanical strength and pore interconnectivity. First step, a-TCP spheres were exposed to acidic calcium phosphate solution to allow growth and interlocking of dicalcium phosphate dihydrate (DCPD) crystals precipitated on the surface of the a-TCP spheres. Then, the DCPD-coated a-TCP spheres were sintered at 1,500°C for 6h, which resulted in the fusion of spheres to form the interconnected porous block. XRD analysis showed single phase a-TCP was obtained. Mechanical strength of porous a-TCP was 6.9 ± 1.6 MPa and porosity was 53 ± 5%. The obtained porous a-TCP could be employed as potential bone substitute or precursor for other bioceramics like carbonate apatite and hydroxyapatite.