Antithrombotic Suture Modification: Long-Term Storage Stability

The aim of the study was to study thromboresistant properties of modified suture material after three-year storage.Materials and Methods. We used polypropylene Serapren 3.0.-based suture. To modify suture material we applied 3% biodegradable poly(3-hydroxybutyrate-co-3-hydroxyvalerate), molecular weight 280 kDa in chloroform on suture surface. Unfractioned heparin was used as a pharmaceutical substance to produce an antithrombotic and antiproliferative effect. Suture material was modified in several stages using a multistep chemical reaction that enabled to rigidly attach the coating on suture surface.Results. The assessment of uniformity and integrity of a modifying layer has revealed a modified suture surface after 3-year storage to remain evenly covered by a biodegradable layer. Spectroscopic study enabled to determine reliably the presence of a heparin layer in the coating, as evidenced by the presence of sulfo groups in spectrum. Histology of biomaterial samples stitched by modified and unmodified suture showed the difference in tissue response to suture. The samples sutured by an unmodified suture material had marked inflammatory signs, significant lymphocyte accumulation being found around. However, the samples with modified sutures showed insignificant lympholeucocytic infiltration.Conclusion. The suggested chemical technique of surgical suture modification is promising, since pronounced antithrombotic properties of the suture and high biocompatibility persist over a three-year period.