The objective of this study was to alleviate the acidity of PLGA nanofiber degradation in vitro by introducing the basic amino acid Lysine (Lys) into the PLGA nanofibers.PLGA and PLGA/Lys composite nanofibers were prepared via electrospinning

and the morphology

thermodynamic and mechanical properties of these nanofibers were characterized by SEM

DSC and mechanical testing

respectively.Release profiles of the Lys from the PLGA-based composite nanofibers were thereafter determined.Morphology of the degraded nanofibers and pH of the PBS solution

in which PLGA and PLGA/Lys nanofibrous mats were soaked at 37 ℃ for up to eight weeks

were assessed to detect the degradation behavior.Finally

cytotoxicity was performed by culturing vascular smooth muscle cells (SMCs) with fluid containing degraded product after eight weeks of degradation.It was found that the release kinetics of Lys from the electrospun PLGA/Lys nanofibers was Lys content dependent.Incorporation of Lys enhanced the degradation process of PLGA and mitigated the decrease of PBS solution pH (acidity).PLGA nanofibers containing 2% Lys are capable of maintaining the pH value between 7.4 and 6.7.Proliferation of SMCs was hindered in the presence of acidic products.But the SMCs grew well in the solution containing degraded products and Lys.