Composite fabricated from the combination of biodegradable polymer and bioactive filler is beneficial for bone tissue
engineering if the biomaterial can perform similar characteristics of the natural inorganic-organic structures of bone.
In this study, we have investigated the thermoplastic starch (TPS)/sol-gel derived bioglass composite as new biomaterial
for bone tissue engineering. The composites were produced using selected TPS/bioglass mass ratio of 100/0, 95/5, 90/10,
85/15 and 80/20 by a combination of solvent casting and salt leaching techniques. Tensile test results showed the addition
of bioglass increased the tensile strength and Young’s modulus, but reduced the elongation at break of the samples. The
modulus of all samples were higher than the requirement for cancellous bone (10-20 MPa). The SEM imaging showed
the presence of porous structure on the surface of all samples. XRD results confirmed the formation of hydroxycarbonate
apatite (HCA) layer on the surface of bioglass containing samples; indicating the occurrence of surface reactions when
the samples were immersed in Simulated Body Fluid (SBF). Furthermore, the presence of P-O stretch band in FTIR
spectrum between 1000 and 1150 cm-1 and Si-O-Si stretch band at 1000 cm-1 also proved the bioactivity of TPS/bioglass
composite. The in vitro biodegradability analysis shows the biodegradability of TPS/bioglass composite decreases with
increasing mass ratio of the bioglass.
The purpose of this study was to prepare macroporous glass ceramic scaffold by sol-gel glass synthesis and powder
sintering method. Sodium nitrate was added during sol-gel process to obtain glass ceramic with mol composition of
42.11% SiO2
- 18.42% CaO - 29.82% Na2
O - 9.65% P2
O5
. The glass particles were found to be thermally stable above
900°C as indicated by TGA/DTA analysis. The dried glass particles obtained from sol-gel process were compacted and
sintered at 1000°C for 3 h soaking time. Sintering crystallized the glass by 71.5% of crystallinity with tetracalcium catenahexaphosphate
(V) (Ca4
(P6
O19) as the main crystalline phase as revealed by XRD analysis. Although glass crystallized
during sintering, it showed a good in vitro bioactivity as apatite-like layer were deposited on the glass ceramic surface
when immersed in simulated body fluid (SBF) for 14 days. SEM analysis proved the macroporous structure formation with
pore size ranges between 30 and 350 µm due to foaming effect which occurred during sintering. Besides that, the glass
ceramic surface formed into vitrified-like due to fluxing effect during sintering thus affected the porosity and densification
measurement done by Archimedes test. In conclusion, the presence of sodium oxide in sol-gel glass ceramic composition
by 29.82 mol % with sintering temperature at 1000°C is able to produce bioactive and macroporous glass ceramic that
potentially be used as medical scaffold material.
Kajian ini bertujuan untuk mengkaji kesan kandungan fosfat berbeza (X = 10, 15 dan 20% mol) terhadap pembentukan
morfologi permukaan, ikatan kimia, penghabluran, fasa dan kekuatan mampatan kaca sol-gel tersinter. Serbuk kaca
gel dengan komposisi 50SiO2
.(50-X).CaO.XP2
O5 (dalam peratusan mol) disediakan melalui kaedah sol-gel, dimampat
membentuk pelet dan disinter pada suhu 1200°C selama 3 jam. Didapati bahawa dengan peningkatan kandungan fosfat,
mikrostruktur kaca tersinter yang lebih padat terhasil disebabkan peningkatan pemadatan jasad, pengurangan keliangan
ketara dan pembentukan butiran dan sempadan butiran berhablur yang lebih besar. Peningkatan sebanyak 20% mol
kandungan fosfat meningkatkan vitrifikasi (fasa kekaca) pada permukaan kaca tersinter yang mana meningkatkan
pemadatan jasad kepada 83.56%, kekuatan mampatan pada 113 MPa dan penurunan peratusan penghabluran pada
sekitar 66%. Analisis EDS menunjukkan peningkatan kandungan fosfat menyebabkan peningkatan unsur Si-O pada fasa
amorfus dan unsur P-O pada fasa berhablur. Analisis FTIR menunjukkan berlaku pemisahan fasa kaya fosfat dan fasa
kaya silikat dan pada masa sama meningkatkan rangkaian tetrahedra silikat (Si-O-Si) dan fosfat (P-O-P) kaca tersinter.
Peningkatan kandungan fosfat meningkatkan kumpulan berfungsi berkaitan fosfat hablur dan mengurangkan kumpulan
berfungsi berkaitan silikat hablur. Ini menyebabkan peningkatan pembentukan fasa silikokarnotit, Ca5 (PO4)2 (SiO4)
dalam matriks kaca tersinter dengan peningkatan kandungan fosfat yang ditunjukkan melalui analisis XRD.