Fabrication And Characterization Of Drug Coating On The Stent

To reduce restenosis rate after the current metal coronary artery stent implanting, we prepared PU and acrylic resin film on biomedical 316L stainless steel surface and finally prepared acrylic resin film loading siromilus drug on the surface of metal stent. The structure and character of the two films were analyzed by using contact angles device, angle X-ray diffraction (XRD), scanning electron microscope (SEM), Fourier Transform Infrared Spectrometer (FTIR), platelet adhesion experiment. Finally, we analyzed and studied the acrylic resin/siromilus matrix.Through the study, the following major conclusions can be drawn:1 The fiber PU coatings is obtained by the spaying technology and phase inversion theory .The results indicates that fibers have augment trend with the higher polymer solution concentration and fiber diameters minish with the higher gas pressure and PU film will be tense at the higher gas condition; the fiber PU coating is superhydrophobic; the fiber film can't effectively reduce the adhesion of the blood platelet and meliorate the antithrombotic ability of the 316L stainless steel surface.2 Electrostatic spray deposition method can be used to fabricate acrylic resin coating on the bare stent. In this paper , we discuss the film-making technology and the acrylic resin film is analyzed by using contact angles device ,canning electron microscope (SEM), and the biocompatibility is investigated by platelet adhesion experiment. The results indicate that acrylic resin has perfect performance and good blood-compatibility and this film are suitable to fabricate the stent coating.3 Finally, the acrylic resin/sirolimus coating was prepared on the surface of stainless steel coronary stents. Characterization of the acrylic resin was performed by using FTIR and DSC , then acrylic resin/sirolimus mixture coating was analyzed by XRD. Further, the in vitro drug release kinetics of the prepared drug-eluting stent was tested by HPLC and the mechanism of drug release was discussed. The results revealed that in the dispersion, the sirolimus was present in amorphous state and the glass temperature of drug film was higher at more drug loading and the solubility of sirolimus in acrylic acid resin was about 10% and sirolimus would be crystallization in 5% drug loading , 3 months Stored conditions and the drug release property from mixture coating was in accord with Higuchi diffusion model.