No abstract

As the three-dimensional (3D) architecture of porcine acellular dermal matrix (pADM) mimics the biological characteristics of a native extracellular matrix (ECM), it has been extensively utilized as a tissue scaffold. In this study, a novel pADM-derived micro-and nano electrospun collagen membrane (PDEC) was successfully prepared by the electrospinning technique, using porcine acellular dermal matrix (pADM) as the raw material and 1,1,1,3,3,3-hexafluoro-2-propanol (HIFP) as the solvent, and was characterized by scanning electron microscopy (SEM) analysis. In contrast, another collagen-derived electrospun collagen (CDEC) was also fabricated using pure porcine collagen as the raw material. The structure and composition of the PDEC and CDEC were measured by Fourier transform infrared (FTIR) spectroscopy, SDS-PAGE gel electrophoresis, specific intrinsic viscosity and atomic force microscopy (AFM). The results indicate that the structural integrity of the PDEC is almost maintained and only a small amount of the PDEC was destroyed into gelatin, while almost all of the CDEC was degraded. Moreover, the results of circular dichroism (CD) analysis also demonstrate that the PDEC possesses a higher content of a-helix structure but less b-turn structure. Additionally, the results from ultrasensitive differential scanning calorimetry (US-DSC) and XRD analysis also suggest that the thermal stability and crystallization of the PDEC have little differences compared to collagen. Furthermore, the mechanical properties of the PDEC are significantly enhanced compared to those of the CDEC. Above all, the results obtained in the MTT study indicate that the PDEC has almost the same good biological activity, in terms of cytotoxicity, as natural porcine collagen, and this activity is obviously superior to that of the CDEC. In conclusion, our study provides a new pADM-derived electrospun collagen in which the triple helical structure has seldom been damaged and thus it can be applied as a novel electrospun collagen scaffold for tissue engineering.

Infection is a common complication in the process of wound management. An ideal wound dressing is supposed to reduce or even prevent the infection while promoting wound healing. A porcine acellular dermal matrix (pADM) has been already used as a wound dressing in clinic due to its capacity to accelerate wound healing. However, not only is pure pADM not antibacterial, its mechanical properties are poor. In this study, an antibacterial pADM with good performance was prepared by adding two natural products as modifiers, quercetin (QCT) and tea tree oil (TTO). The result of Fourier-transform infrared (FTIR) proved that the addition of modifiers did not break the natural triple-helical structure of collagen. Meanwhile, the results of differential scanning calorimetry (DSC), thermogravimetric analysis (TG), mechanic experiment, and enzymatic degradation demonstrated that pADM handled with QCT and TTO (termed QCT–TTO–pADM) had better thermal stability, mechanical strength, and resistance to enzymatic degradation than pADM. Meanwhile, QCT–TTO–pADM had excellent antibacterial activity and showed an antibacterial rate of over 80%. Furthermore, in the cytocompatibility analysis, QCT–TTO–pADM had no side effects on the adhesion, growth, and proliferation of fibroblasts. QCT–TTO–pADM could even accelerate wound healing more efficiently than pADM and glutaraldehyde-modified pADM (GA-pADM). In conclusion, QCT–TTO–pADM was a potential antibacterial wound dressing with good performance.