Sains Malaysiana 45(12)(2016): 1779–1785

http://dx.doi.org/10.17576/jsm-2016-4512-01

Mekanisme Pembentukan Apatit pada Permukaan Sampel β-Wolastonit yang Dihasilkan daripada Abu Sekam Padi

(Mechanism of Apatite Formation on β-wollastonite Sample Surface Synthesized from

Rice Husk Ash)

HAMISAH ISMAIL, ROSLINDA SHAMSUDIN*, MUHAMMAD AZMI ABDUL HAMID

& ROZIDAWATI AWANG

Pusat Pengajian Fizik Gunaan, Fakulti Sains & Teknologi, Universiti Kebangsaan Malaysia

43600 Bangi, Selangor Darul Ehsan, Malaysia

Diserahkan: 8 Oktober 2015/Diterima: 25 Mac 2016

ABSTRAK

Mekanisme pembentukan apatit pada permukaan β-wolastonit dikaji. β-wolastonit dihasilkan daripada teknik sol-gel menggunakan abu sekam dan batu kapur terkalsin sebagai bahan pemula dengan nisbah CaO:SiO₂ adalah 55:45. Kebioaktifan sampel β-wolastonit dikaji dengan merendam sampel berbentuk silinder dalam larutan simulasi badan (SBF) untuk tempoh yang ditetapkan iaitu 1, 3, 7 dan 14 hari. Komposisi permukaan, morfologi dan perubahan struktur sampel sebelum dan selepas direndam dianalisis melalui pembelauan sinar-X (XRD) dan mikroskop elektron imbasan (FESEM) yang digabungkan dengan EDX. Keputusan XRD menunjukkan fasa β-wolastonit berjaya dihasilkan selepas dimasukkan ke dalam autoklaf untuk 8 jam pada suhu 135°C pada tekanan 0.24 MPa dan disinter 2 jam pada suhu 950°C. Apatit didapati tumbuh pada permukaan sampel β-wolastonit selepas 7 hari rendaman dalam larutan SBF. Semasa proses rendaman dalam larutan SBF, 2 jenis kumpulan kalsium fosfat dihasilkan iaitu amorfus kalsium fosfat (ACP) selepas 3 hari rendaman dengan julat nisbah Ca/P 1.2-2.02 dan pada hari ke-14 membentuk hidroskiapatit kurang kalsium (CDHA) dengan nisbah Ca/P 1.63. Perubahan fasa sampel β-wolastonit daripada keadaan hablur kepada amorfus jelas terbukti daripada keputusan XRD selepas direndam dalam SBF dengan penurunan puncak keamatan bagi sampel β-wolastonit pada sudut belauan 30°. Ini mengukuhkan mekanisme pembentukan lapisan apatit pada permukaan sampel β-wolastonit dan ianya bersifat bioaktif.

Kata kunci: Abu sekam; apatit; batu kapur terkalsin; β-wolastonit; kebioaktifan

ABSTRACT

The mechanism of apatite formation on the β-wollastonite surface was studied. β-wollastonite was produced using the sol-gel technique from rice husk ash and calcined limestone as the starting material with CaO:SiO₂ ratio of 55:45. Bioactivity of the β-wollastonite sample was studied by immersing a cylindrical form sample in a simulation body fluid solution (SBF) for a period of 1, 3, 7 and 14 days. Surface composition, morphology and structural of the sample before and after immersion were analyzed using X-ray diffraction (XRD) and scanning electron microscope (FESEM) coupled with EDX. The XRD results showed that β-wollastonite was successful obtained after autoclaving for 8 h at 135°C, with pressure at 0.24 MPa and sintered for 2 h at 950°C. Apatite was found to growth on the surface of β-wollastonite after 7 days of immersion in the SBF solution. During immersion in the SBF solution, two types of calcium phosphate groups were obtained, which is amorphous calcium phosphate (ACP) after 3 days of immersion with Ca/P ratio in the range of 1.2-2.02 and on the 14th day, calcium deficient hydroxyapatite (CDHA) is formed with the molar ratio Ca/P 1.63. Phase transformation from crystalline to an amorphous was clearly been detected from the XRD results through the decreasing of the peak intensity at 2 theta of 30.00 after immersing in the SBF. This supports the occurring of apatite formation mechanism on the β-wollastonite surface and possesses bioactive property.

Keywords: Apatite; bioactivity; β-wollastonite; calcined limestone; rice husk ash

RUJUKAN

Adam, F., Jimmy, N.A. & Anwar, I. 2012. The utilization of rice husk silica as a catalyst: Review and recent progress. Catalysis Today 190: 2-14.

Blanton, T.N. & Craig, L.B. 2005. Quantitative analysis of calcium oxide desiccant conversion to calcium hydroxide using X-ray diffraction. International Centre for Diffraction Data 48: 45-51.

Cölfen, H. 2010. Biomineralization: A crystal-clear view. Nature Materials 9: 960-961.

Daud, N.K. & Hameed, B.H. 2010. Decolorization of acid red 1 by fenton-like process using rice husk ash-based catalyst. Journal of Hazardous Materials 176: 938-944.

Dorozhkin, S.V. 2010. Bioceramics of calcium orthophosphates. Biomaterials 31: 1465-1485.

Huang, X.H. & Chang, J. 2009. Synthesis of nanocrystalline wollastonite powders by citrate-nitrate gel combustion method. Materials Chemistry and Physics 115: 1-4.

Ismail, H., Nizam, J.M. & Abdul Khalil, H.P.S. 2001. The effect of a compatibilizer on the mechanical properties and mass swell of white rice husk ash filled natural rubber/linear low density polyethylene blends. Polymer Testing 20: 125-133.

Jenkins, B.M., Baxter, L.L., Miles Jr, T.R. & Miles, T.R. 1998. Combustion properties of biomass. Fuel Processing Technology: 54(1): 17-46.

Kokubo, T. & Takadama, H. 2006. How useful is SBF in predicting in vivo bone bioactivity? Biomaterials 27: 2907- 2915.

Kumar, A., Mohanta, K., Kumar, D. & Parkash, O. 2012. Properties and industrial applications of rice husk: A review. International Journal of Emerging Technology and Advanced Engineering 2: 86-90.

Kusbiantoro, A., Muhd Fadhil, N., Nasir, S. & Sobia, A.Q. 2012. The effect of microwave incinerated rice husk ash on the compressive and bond strength of fly ash based geopolymer concrete. Construction and Building Materials 36: 695-703.

Lee, T., Radzali, O. & Yeoh, F-Y. 2013. Development of photoluminescent glass derived from rice husk. Biomass and Bioenergy 59: 380-392.

Li, P. & Zhang, F. 1990. The electrochemistry of a glass surface and its application to bioactive glass in solution. Journal of Non-Crystalline Solids 119: 112-118.

Lin, K., Jiang, C., Ziwei, L., Yi, Z. & Ruxiang, S. 2009. Fabrication and characterization of 45S5 bioglass reinforced macroporous calcium silicate bioceramics. Journal of the European Ceramic Society 29: 2937-2943.

Liu, X., Ding, C. & Chu, P.K. 2004. Mechanism of apatite formation on wollastonite coatings in simulated bodyfluid. Biomaterials 25: 1755-1761.

Mallick, K. 2014. Bone Substitutes Materials.1st ed. Cambridge: Woodhead publishing in series biomaterials. Number 78.

Noor Sheeraz, C.Z., Ismail, A.R., Dasmawati, M. & Adam, H. 2013. A green sol-gel route for the synthesis of structurally controlled silica particles from rice husk for dental composite filler. Ceramics International 39: 4559-4567.

Ramesh, S., Tan, C.Y., Bhaduri, S.B., Teng, W.D. & Sopyan, I. 2008. Densification behaviour of nanocrystalline hydroxyapatite bioceramics. Journal of Materials Processing Technology 206: 221-230.

Rashita, A.R., Roslinda, S., Muhammad Azmi, A.H. & Azman, J. 2014. In-vitro bioactivity of wollastonite materials derived from limestone and silica sand. Ceramics International 40: 6847-6853.

Shumkova, V.V., Pogrebenkov, V.M., Karlov, A.V., Kozik, V.V. & Vereshchagin, V.I. 2001. Hydroxyapatite-wollastonite bioceramics. Glass and Ceramics 57: 350-353.

Sopyan, I. & Jasminder, K. 2009. Preparation and characterization of porous hydroxyapatite through polymeric sponge method. Ceramics International 35: 3161-3168.

Sunarso, Ahmad Fauzi, M.N., Shah Rizal, K., Radzali, O., Ika, D.A. & Ishikawa, K. 2013. Synthesis of biphasic calcium phosphate by hydrothermal route and conversion to porous sintered scaffold. Journal of Biomaterials and Nanobiotechnology 04: 273-278.

Umamaheswaran, K. & Batra, V.S. 2008. Physico-chemical characterisation of Indian biomass ashes. Fuel 87: 628-638.

Wan, X., Chengkang, C., Dali, M., Ling, J. & Ming, Li. 2005. Preparation and in vitro bioactivities of calcium silicate nanophase materials. Materials Science and Engineering: C 25: 455-461.

Zhao, J.C. 2007. Methods for Phase Diagram Determination. New York: Elsevier.

Zhao, W. & Chang, J. 2004. Sol-gel synthesis and in vitro bioactivity of tricalcium silicate powders. Materials Letters 58(19): 2350-2353.

*Pengarang untuk surat-menyurat; email: linda@ukm.edu.my