A Study of Bone-Like Apatite Formation on β-TCP/PLLA Scaffold in Static and Dynamic Simulated Body Fluid

Abstract

The ability of apatite to form on the surface of biomaterials in simulated body fluid (SBF) has been widely used to predict the bone-bonding ability of bioceramic and bioceramic/polymer composites in vivo. Porous β-tricalcium phosphate/poly(L-lactic acid) (β-TCP/PLLA) composite scaffold was synthesized by new method. The ability of inducing calcium phosphate (Ca-P) formation was compared in static simulated body fluid(sSBF) and dynamic simulated body fluid (dSBF). The Ca-P morphology and crystal structures were identified using SEM, X-ray diffraction and Fourier transform infrared (FT-IR) spectroscopy. The results showed that the typical features of bone-like apatite formation on the surface and the inner pore wall of β-TCP/PLLA. Ca-P formation on scaffold surfaces in dSBF occurred slower than in sSBF and was more difficult with increasing flow rate of dSBF. The ability of apatite to form on β-TCP/PLLA was enhanced by effect of each other that has different degradable mechanism. Porous β-TCP/PLLA composite scaffold indicates good ability of Ca-P formation in vitro.

The Structural, Thermal and Morphological Characterization of Polylactic Acid/Β-Tricalcium Phosphate (PLA/Β-TCP) Composites upon Immersion in SBF: A Comprehensive Analysis

“…The band at 1450 cm −1 is attributed to the C-H stretching vibration in methyl groups, while the bands at 1381 and 1362 cm −1 are attributed to symmetric and asymmetric vibrations of -CH- bending. Additionally, the peak at 752 cm −1 is attributed to the C-C stretching vibration [ 21 , 32 ]. On the other hand, β-TCP shows typical absorption bands at 1088, 550, and 608 cm −1 (bending out of the plane of the PO 4 3− group); 1037 cm −1 (the asymmetric vibration of the PO 4 3− group); and 962 cm −1 (the asymmetric vibration of the PO 4 3− group) [ 12 ].…”

“…This result agrees with the findings of Backes et al [ 7 ], who studied the immersion of the same type of composites in an SBF solution and detected HCA formation after incubation for 21 days. Studies from Kang et al [ 21 ] have revealed the formation of octacalcium phosphate (OCP) and hydroxyapatite (HAp) on the surface of PLLA/TCP scaffolds after incubation in static SBF and dynamic SBF for 28 days.…”

“…It is well established that bioactive materials immersed in an SBF solution engage in ion exchange processes, ultimately forming hydroxyapatite layers on the material’s surface, a common feature of their bioactivity. The bioactivity of PLA/β-TCP biocomposites has been demonstrated by various authors using different techniques such as X-ray diffraction, Fourier transform infrared spectroscopy (FTIR-ATR) analysis, scanning electron microscopy (SEM) and EDX [ 12 , 21 , 22 , 23 ]. Thermogravimetric analysis (TGA) has also been utilized to demonstrate that tricalcium phosphate (TCP) is transformed into hydroxyapatite (HA) [ 12 ].…”