The biggest advantage of using the spin coating process is the absence of coupled process variables (variables that depend on one another). The film-forming process is mainly driven by two independent parameters: the viscosity and the speed of rotation. The biggest impacts on the final thickness of the coating are the flow control stage (removal of excess solution) and evaporation. Spin coating is a physical process used to create uniform thin films (at the micrometric or nanometric level) on a flat surface (ceramic, metallic, or polymer surfaces) using centrifugal force. One of the methods used for this purpose is the method called “spin coating”. This film should be uniform and should ensure a smooth non-thrombogenic surface with antibacterial properties.
Ī technique used to modify the surface of the material in order to obtain materials with improved properties so they can be used in biomedical applications is to cover the material with a polymeric thin film. One of the most-used materials is PVC, due to its unique properties (mechanical strength and chemical resistance, is inert to biological fluids, has anti-aging properties, presents a wide range of possibilities for processing (mixing, pouring, extrusion, etc.), and is reasonably priced, even for the material devoted to medical applications. Among the most important polymers used as biomaterials in the medical field are polyurethane, silicone rubber, ethylene vinyl acetate, polyvinyl chloride (PVC), polycarbonate, polyester, polyacrylonitrile, hydrogels, etc. To overcome these drawbacks, many studies have been conducted on several materials. Intra-cardiac catheter introduction for experimental or diagnostic purposes and its maintenance for a period of 7–14 days can cause valvular or parietal endocarditis. Thrombogenicity due to incompatibility of the material surface and the change in the flow dynamics at the site of implant are the most common causes that lead to failure of the device. Also, such devices have some important drawbacks, such as structure failure, calcifications, infections, thrombosis, etc. Catheters are used in treating vascular diseases and can also provide fluid administration, parenteral nutrition, hemodynamic monitoring, blood sampling, and administration of drugs. One of the most important classes of medical devices are catheters, which can be used as diagnostic tools and also as clinical tools. Because of this, it is necessary to obtain some new or improved materials for preparing cardiovascular devices, including vascular grafts for bypass, stents, and heart valves that provide the desired interactions between the material and body fluids, especially blood. PVC modified using the proposed method showed a good ability to prevent salt deposition and decreased the protein adhesion, and the resistance to bacterial adherence was improved compared with standard PVC.Ĭardiovascular diseases are responsible for a large number of deaths and it is estimated that this number will grow in the coming years. The concentration of dicoumarol at the surface of the material and also the release rate is important for the applications for which the surface modification was designed. Results: The material obtained had a smooth surface with a uniform distribution of dicoumarol, which is released depending on the deposition parameters. aeruginosa ATCC 27853) standard strains from American Type Culture Collection (ATCC). aureus ATCC 25923) and Gram-negative ( P. The samples were tested for Gram-positive ( S.
The modified surfaces were analyzed by Fourier-transform infrared (FT-IR) microscopy, Fourier-transform infrared (FT-IR) spectroscopy, Ultraviolet-visible spectroscopy (UV-VIS), and Scanning electron microscopy (SEM) in order to determine the surface morphology and behavior. Materials and Methods: The surface of PVC was modified by depositing a thin layer also of PVC that incorporates an active substance, dicoumarol (a well-known anticoagulant), by spin coating process. The aim of this work is to modify the surface of polyvinyl chloride (PVC), an affordable biocompatible material, in order to reduce these aforementioned side effects. Unfortunately, they present some important drawbacks (structure failure, calcifications, infections, thrombosis, etc.), with the main side effects occurring due to adhesion and proliferation of bacteria and living cells on the surface of the implanted devices. Background and objectives: Medical devices such as catheters are used on a large scale to treat heart and cardiovascular diseases.