Evaluating biodegradation rates in neat PCL- and PCL/PLA-based biocompatible tubular scaffolds

Abstract

Vascular grafts are synthetic tubular structures that play an important role in replacing damaged vessels in the treatment of cardiovascular diseases. Existing grafts, especially in small-diameter vessels, face persistent issues such as thrombosis, immune rejection, and mechanical limitations. Vascular grafts designed with an innovative perspective to overcome these deficiencies are tubular scaffolds with a biodegradable structure and a layered design that mimics the native artery structure. This study focuses on the development of biodegradable and biocompatible tubular scaffolds with randomly distributed and radially oriented fibers in different layers to replicate the native structure of artery, utilizing neat polycaprolactone (PCL) and PCL/polylactic acid (PLA) blend with 4/1 polymer blend ratio. Electrospinning technique is employed to fabricate tubular fibrous structures. The biodegradation profiles of these scaffolds are assessed at 3, 6, and 9 months, with comparative analyses conducted to explore how polymer type and orientation level influence degradation rates and the structural integrity of the materials over time. The findings reveal that scaffolds with randomly distributed fibers exhibit higher biodegradation rates compared to those with oriented fibers, particularly in the PCL/PLA blends. Specifically, the study identifies PCL_R as having the highest degradation rate at 61% weight loss by the 9th month. Importantly, while PCL is known for its slow degradation, the high molecular weight of PLA leads to a slower degradation profile in the PCL/PLA samples. These insights underscore the critical role of scaffold morphology and composition in optimizing the performance and functionality of vascular grafts, highlighting the need for scaffolds that support cellular activities while effectively degrading to facilitate tissue regeneration without toxic effects.