| Drug-eluting stent is the most effective therapeutic method in percutaneous coronary intervention (PCI). The key components are the selection and preparation of drug -carring materials and coated materials. With good biocompatible and biodegradable proprieties, polyesters, polylactic acid (PLA) and its copolymer PLGA are used in medicine area, especially in controlled and prolonged release of drug. In this article, a fabrication technology of micro-porous polymer drug coating on 316L stainless steel was studied and so were the coating's degradation behavior and blood compatibility.From the results of the examination, it can be concluded that a PLGA coating homogeneous in size and distribution of the pores can be fabricated on 316L stainless steel matrix by water assisted self-assembly method through casting and dipping. The driving force of this self-assembly procedure is capillary force and the water droplets play the role as template. The pore-size can be controlled in a range from 1μm to 10μm by controlling the relative humidity, concentration of the polymer solution and other parameters.The compact PLGA coating has a weaker hydrophilicity than 316L stainless steel, and becomes more hydrophobic with the increasing of percentage composition of LA. The porous PLGA coating has a hydrophobicity and becomes stronger with the increasing of the pore-size.Compared to naked 316L stainless steel, the compact and porous PLGA coatings can improve blood compatibility.During the primary degradation, the degradation of compact and porous coatings don't accompany with the falling-off of in large area and can be used in animal experiment.Electrostatic spray deposition method can be used to fabricate PLGA coating with good surface quality.
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