Investigating composite systems based on poly L-lactide and poly L-lactide/triclosan nanoparticles for tissue engineering and medical applications.

In this study, the encapsulated triclosan with a low molecular weight PLLA (LATC30) is dispersed into a PLLA having higher molecular weight via melt blending to increase the overall properties and particularly antibacterial activity of the system. The proposed method results in a completely homogenous composite as 5% LATC30 improved mechanical properties. For instance, the elongation at break was increased ca. 3%. The mechanical properties of the fabricated composites were also affected by the plasticizing role of LATC30. The kinetics of hydrolytic degradation in an accelerated condition was obtained using a novel method by the Beer-Lambert equation. It was found that the incorporation of LATC30 into the composite increases the rate of hydrolytic degradation. The calorimetry showed a reduction in crystallinity upon addition of LATC30. Moreover, the degradation of the composites was studied and fully described the kinetic analysis by the Flynn-Wall-Ozawa (FWO) method. From which, it was found that the activation energy of the system was decreased. As the LATC30 content of the composite was increased, the hydrophilicity of the composite was increased. The fabricated scaffolds with 5% LATC30 demonstrated a good osteoblast cell attachment and mineralization on the composite scaffolds. This composite is a suitable antibacterial candidate for the bone tissue engineering and medical applications since the real dosage of triclosan stays at ca. 1.5%.