Usage of different vessel models in a flow-through cell: in vitro study of a novel coated balloon catheter

Drug-coated balloon catheters are a novel clinical treatment alternative for coronary and peripheral artery diseases. Calcium alginate, poly(vinylethylimidazolium bromide) and polyacrylamide hydrogels were used as vessel models in this in vitro study. In comparison to a simple silicone tube their properties can be easily modified simulating different types of tissue. Local drug delivery after balloon dilation in the first crucial minute was determined in a vessel-simulating flow-through cell by a simulated blood stream. Balloon catheters were coated with paclitaxel using the ionic liquid cetylpyridinium salicylate as a novel carrier. Drug transfer from coated balloon catheters to different simulated vessel walls was evaluated and compared to a silicone tube. The highest paclitaxel delivery upon dilation was achieved with calcium alginate as the vessel model (60%) compared to polyacrylamide with 20% drug transfer. The silicone tube showed the least amount of wash-off (<1%) by a simulated blood stream after one minute from the vessel wall. The vessel-simulating flow-through cell was combined with a model coronary artery pathway to estimate drug loss during simulated use in an in vitro model. Calcium alginate and polyacrylamide hydrogels were used as tissue models for the simulated anatomic implantation process. In both cases, similar transfer rates for paclitaxel upon dilation were detected.