The in vitro and in vivo degradation behaviour of poly (ε-caprolactone) (PCL) has been examined in terms of degree of degradation and morphological change during an inclibation period of up to 300 d. Gel permeation c...The in vitro and in vivo degradation behaviour of poly (ε-caprolactone) (PCL) has been examined in terms of degree of degradation and morphological change during an inclibation period of up to 300 d. Gel permeation chromatography (GPC) and differential scanning calorimetry (DSC) were employed to character ize their degradation profiles. The observation of the changes in intrinsic viscosity and average molecular weight as well as the crystallinity of PCL leads to the findings that 2 degradation mechanisms of PCL exist. The subcutaneous implant test shows that the rate of degradation in the rabbit body is much higher than in vitro. This illustrated that in vivo, the mechanism of bioerosion is more important than hydrolytic cleavage of ester linkage, especially in the second stage of degradation. Regardless of the initial Mn of specimens, a lin ear relationship between Mn and degradation time has been observed until the Mn decreased to be about 5 ooo D. Above this figure, the main degradation mechanism was hydrolytic cleavage of ester group accompa nied by enzymatic surface erosion, below this point, the bioerosion with weight loss plays a more significant role than hydrolytic reaction in their degradation. Comparison between the morphology of PCL materials af ter and before erosion was made by means of scanning electron microscopy (SEM).展开更多
In our study, the mechanical properties and degradability of vascular grafts made from poly(ε-caprolactone)(PCL) and poly(lactic-co-glycolic acid)(PLGA) at different ratios were investigated. The results showed that ...In our study, the mechanical properties and degradability of vascular grafts made from poly(ε-caprolactone)(PCL) and poly(lactic-co-glycolic acid)(PLGA) at different ratios were investigated. The results showed that the electrospun PCL/PLGA grafts possess good mechanical properties and biodegradability. The tensile and burst strength of the scaffolds met the demands of vascular grafts. In vitro degradation tests indicated that the degradation rate of the materials increased with the percentage of PLGA, and in vivo tests showed that increasing the amount of PLGA is an effective way to promote cell infiltration. Particularly, the electrospun PCL/PLGA blended scaffold with 10% PLGA exhibited a balance of mechanical and degradation properties, making it a promising tissue engineering material for vascular grafts.展开更多
文摘The in vitro and in vivo degradation behaviour of poly (ε-caprolactone) (PCL) has been examined in terms of degree of degradation and morphological change during an inclibation period of up to 300 d. Gel permeation chromatography (GPC) and differential scanning calorimetry (DSC) were employed to character ize their degradation profiles. The observation of the changes in intrinsic viscosity and average molecular weight as well as the crystallinity of PCL leads to the findings that 2 degradation mechanisms of PCL exist. The subcutaneous implant test shows that the rate of degradation in the rabbit body is much higher than in vitro. This illustrated that in vivo, the mechanism of bioerosion is more important than hydrolytic cleavage of ester linkage, especially in the second stage of degradation. Regardless of the initial Mn of specimens, a lin ear relationship between Mn and degradation time has been observed until the Mn decreased to be about 5 ooo D. Above this figure, the main degradation mechanism was hydrolytic cleavage of ester group accompa nied by enzymatic surface erosion, below this point, the bioerosion with weight loss plays a more significant role than hydrolytic reaction in their degradation. Comparison between the morphology of PCL materials af ter and before erosion was made by means of scanning electron microscopy (SEM).
基金supported by National Key Research and Development Program of China(No.2017YFC1103500)National Natural Science Foundation of China(No.81671842)Natural Science Foundation of Tianjin,China(No.16JCZDJC37600)
文摘In our study, the mechanical properties and degradability of vascular grafts made from poly(ε-caprolactone)(PCL) and poly(lactic-co-glycolic acid)(PLGA) at different ratios were investigated. The results showed that the electrospun PCL/PLGA grafts possess good mechanical properties and biodegradability. The tensile and burst strength of the scaffolds met the demands of vascular grafts. In vitro degradation tests indicated that the degradation rate of the materials increased with the percentage of PLGA, and in vivo tests showed that increasing the amount of PLGA is an effective way to promote cell infiltration. Particularly, the electrospun PCL/PLGA blended scaffold with 10% PLGA exhibited a balance of mechanical and degradation properties, making it a promising tissue engineering material for vascular grafts.