Fabrication and characterization of PLLA/Mg composite tube as the potential bioresorbable/biodegradable stent(BRS)

A deeper understanding is required to develop a bioresorbable stents (BRS) for cardiovascular diseases. In this work, the biodegradable composite tubes were produced by adding 2% and 4% w/w of Magnesium (Mg) microparticles with Poly-L-lactic acid (PLLA) to achieve synergism effect. Tubes of diameter 3 mm and thickness of 150 µm were fabricated through a biaxial extrusion (BAE) process. After that, BAE tubes were cut on the Femtosecond laser for making BRS. Mg microparticles were uniformly distributed and completely encapsulated within the PLLA matrix. The thermal analysis and XRD results indicate that Mg microparticles act as a nucleating agent and promotes the crystallinity to the matrix. FTIR analysis reveals the interfacial bonding between Mg and PLLA. Thus, Mg microparticles can act as a reinforcement to the matrix, which improves the toughness, compressive strength as well as ductility as compared to pure PLLA tubes. The degradation study was carried out to explore the effect of Mg as it effectively neutralizes the acidic by-product of PLLA. As a result, the alkaline nature of Mg stabilizes the pH of the body fluid and reduces tissue necrosis. In-vitro cytocompatibility test was performed by L929 fibroblasts cells to identify the potential application of PLLA/Mg composite BAE tubes as a BRS for the future.