Performance evaluation of poly (l-lactide-co-D, l-lactide)/poly (acrylic acid) blends and their nanofibers for tissue engineering applications.

Poly (l-lactide-co-D, l-lactide) (PLDLLA) is a biodegradable polymer predominantly used in biomedical applications. Despite unprecedented characteristics of PLDLLA, its wettability, mechanical properties, degradation, and cell attachment are main issues to improve. In this work, different blend films based on PLDLLA/poly (acrylic acid) (PAAc) are prepared to evaluate their miscibility, hydrophilicity, hydrolytic degradation and mechanical properties. For this purpose, a series of experiments such as DSC alongside SEM, water contact angle (WCA)/water up-take, weight measurements in phosphate buffer saline (PBS) and NaOH as well as tensile test are carried out. The DSC and SEM results show a miscibility for the blends, and hence by increasing PAAc, the WCA values and degradation rates are decreased and increased, respectively. Moreover, the degradation mechanisms of the blend samples follow surface/bulk erosion and bulk process in the alkaline and PBS environments, respectively. Subsequently, PLDLLA and its blends are electrospun to prepare nanofibrous samples, thereby assessing their cytotoxicity and cell viability by the use of thiazolyl blue assay and acridine orange/ethidium bromide staining, respectively. The in vitro SNL 76/7 fibroblast cells cultivation onto the surface of the blend with 10% wt. of PAAc revealed that this sample is a promising candidate for tissue engineering applications.