Fabrication and evaluation of bioresorbable scaffolds for interventional cardiology application with sufficient drug release

Objective(s): Bioresorbable scaffolds have been advocated as the new generation in interventional cardiology because they could provide temporary scaffolds and then disappear with resorption. Although, the available stents in clinical trials exhibited biosafety, efficacy, no death, and no apparent thrombosis, Mg-substrate degradation on drug release has not been investigated.Materials and Methods: Therefore, more research has been needed to legitimize the replacement of current stents with Mg-based stents. UV-Vis spectrophotometer, scanning electron microscope (SEM), X-ray diffraction (XRD), pH measurement, H₂ evolution, and corrosion tests determined the change in hybrid properties and drug release rate. Results: The effect of Mg degradation on drug release from poly-L-lactide (PLLA) specimen was much higher than that of the L۶۰۵/PLLA sample. Hydrogen evolution caused by magnesium degradation compelled everolimus out without significant PLLA decomposition during the first ۱۰۰ days, while formation of Mg(OH)۲ caused the PLLA to deform and crack. Conclusion: A combined mechanism of lattice/hole diffusion-dissolution governed the release of everolimus with the activation energies of ۵.۴۰۹ kJ/mol and ۴.۹۳۶ kJ/mol for the first ۲۴ hr and diffusion coefficients ۶.۰۶×۱۰-۱۰ and ۳.۶۴×۱۰-۱۱cm۲/s for the ۵۰th to ۱۰۰th days. Prolonged suppression of hyperplasia within the smooth muscle cells by hybrid stent insertion could bring about the cessation of restenosis.

کلیدواژه ها:

Coronary Stent ، Degradation ، Diffusion ، Drug Delivery ، Nano-hybrid