[Electrospun polycaprolactone/collagen type nanofibers oriented patch for rotator cuff repairing].

OBJECTIVE

Electrospinning technique was used to manufacture polycaprolactone (PCL)/collagen typeⅠ nanofibers orientated patches and to study their physical and chemical characterization, discussing their feasibility as synthetic patches for rotator cuff repairing.

METHODS

PCL patches were prepared by electrospinning with 10% PCL electrospinning solution (control group) and PCL/collagen typeⅠorientated nanofibers patches were prepared by electrospinning with PCL electrospinning solution with 25% collagen type Ⅰ(experimental group). The morphology and microstructure of the two patches were observed by gross and scanning electron microscopy, and the diameter and porosity of the fibers were measured; the mechanical properties of the patches were tested by uniaxial tensile test; the composition of the patches was analyzed by Fourier transform infrared spectroscopy; and the contact angle of the patch surface was measured. Two kinds of patch extracts were co-cultured with the third generation of rabbit tendon stem cells. Cell counting kit 8 (CCK-8) was used to detect the toxicity and cell proliferation of the materials. Normal cultured cells were used as blank control group. Rabbit tendon stem cells were co-cultured with the two patches and stained with dead/living cells after 3 days of culture, and laser confocal scanning microscopy was used to observe the cell adhesion and activity on the patch.

RESULTS

Gross and scanning electron microscopy showed that the two patch fibers were arranged in orientation. The diameter of patch fibers in the experimental group was significantly smaller than that in the control group ( =26.907, =0.000), while the porosity in the experimental group was significantly larger than that in the control group ( =2.506, =0.032). The tensile strength and Young's modulus of the patch in the experimental group were significantly higher than those in the control group ( =3.705, =0.029; =4.064, =0.034). Infrared spectrum analysis showed that PCL and collagen type Ⅰ were successfully mixed in the experimental group. The surface contact angle of the patch in the experimental group was (73.88±4.97)°, which was hydrophilic, while that in the control group was (128.46±5.10) °, which was hydrophobic. There was a significant difference in the surface contact angle between the two groups ( =21.705, =0.002). CCK-8 test showed that with the prolongation of culture time, the cell absorbance ( ) value increased gradually in each group, and there was no significant difference between the experimental group and the control group at each time point ( >0.05). Laser confocal scanning microscopy showed that rabbit tendon stem cells could adhere and grow on the surface of both patches after 3 days of culture. The number of cells adhered to the surface of the patches in the experimental group was more than that in the control group, and the activity was better.

CONCLUSION

PCL/ collagen type Ⅰ nanofibers orientated patch prepared by electrospinning technology has excellent physical and chemical properties, cell adhesion, and no cytotoxicity. It can be used as an ideal scaffold material in tendon tissue engineering for rotator cuff repair in the future.