Electrospun POSS integrated poly(carbonate-urea)urethane provides appropriate surface and mechanical properties for the fabrication of small-diameter vascular grafts

This study developed a platform for fabricating small-diameter vascular grafts using electrospun poly(carbonate-urea)urethane bonded with different concentrations of POSS nanocage. The characteristics of electrospun POSS-PCUUs were investigated by ATR-FTIR, 1HNMR, EDS, SEM, AFM, WCA, and DSC analyses. Besides, mechanical attributes such as tensile strength, modulus, elastic recovery, and inelastic behaviors were monitored. The survival rate and cellular attachment capacity were studied using human endothelial cells during a 7-day culture period. The results showed that electrospun nanofibers with 6 wt.% POSS-PCUU had better surface properties in terms of richness of POSS nanocage with notable improved mechanical strength and hysteresis loss properties (p < 0.05). The surface roughness of electrospun 6 wt.% POSS-PCUU reached 646 ± 10 nm with statistically significant differences compared to the control PCUU and groups containing 2, 4 wt.% POSS-PCUU (p < 0.05). The addition of 6 wt.% POSS increased the ultimate mechanical strength of nanofibers related to control PCUU and other groups (p < 0.05). The expansion of human endothelial cells on the 6 wt.% POSS-PCUU surface increased the viability reaching maximum levels on day 7 (p < 0.05). Immunofluorescence imaging using DAPI staining displayed the formation single-layer endothelial barrier at the luminal surface, indicating an appropriate cell-to-cell interaction.