Aligned poly(L‐lactic‐co‐e‐caprolactone) electrospun microfibers and knitted structure: A novel composite scaffold for ligament tissue engineering

Abstract

We developed a novel technique involving knitting and electrospinning to fabricate a composite scaffold for ligament tissue engineering. Knitted structures were coated with poly(L-lactic-co-e-caprolactone) (PLCL) and then placed onto a rotating cylinder and a PLCL solution was electrospun onto the structure. Highly aligned 2-microm-diameter microfibers covered the space between the stitches and adhered to the knitted scaffolds. The stress-strain tensile curves exhibited an initial toe region similar to the tensile behavior of ligaments. Composite scaffolds had an elastic modulus (150 +/- 14 MPa) similar to the modulus of human ligaments. Biological evaluation showed that cells proliferated on the composite scaffolds and they spontaneously orientated along the direction of microfiber alignment. The microfiber architecture also induced a high level of extracellular matrix secretion, which was characterized by immunostaining. We found that cells produced collagen type I and type III, two main components found in ligaments. After 14 days of culture, collagen type III started to form a fibrous network. We fabricated a composite scaffold having the mechanical properties of the knitted structure and the morphological properties of the aligned microfibers. It is difficult to seed a highly macroporous structure with cells, however the technique we developed enabled an easy cell seeding due to presence of the microfiber layer. Therefore, these scaffolds presented attractive properties for a future use in bioreactors for ligament tissue engineering.

Fabrication of Electrospun Poly(L-Lactide-co-ɛ-Caprolactone)/Collagen Nanoyarn Network as a Novel, Three-Dimensional, Macroporous, Aligned Scaffold for Tendon Tissue Engineering

“…The scaffolds fabricated by electrospinning exhibit high porosity and micro-to nano scale topography, similar to the structure of natural ECM, 14 and are widely used in the engineering of various tissues, including vascular tissues, myocardial tissues, bone, skin, cartilage, and tendons/ligaments. [15][16][17][18][19][20] With its high elasticity and capacity for recovery from elastic deformation, poly(l-lactide-co-e-caprolactone) [P(LLA-CL)] copolymer is often applied as a mechanostimulating tissue engineering scaffold for tendon/ligament, 20,21 blood vessel, 22 and cartilage 23 engineering applications. The biodegradable copolymer P(LLA-CL) (50:50) could be useful as a provisional functional scaffold in muscular and cardiovascular tissue engineering.…”

Biodegradable polymers for dental tissue engineering and regeneration

“…Moreover, it has low tensile strength (~23 MPa), but very high elongation at breakage (4700 %) making it a good elastic biomaterial [81] [182]. PCL is used in the production of implants composed of adhered nano/microspheres [183], electrospun fibers [184,185], or porous networks [186] used for regeneration of bone [187,188], ligament [189,190], cartilage [191], nerve [192], and vascular tissues [193]. In addition, PCL is often blended or copolymerized with other polymers like polyesters and polyethers to expedite overall polymer erosion [194].…”

Polymer Chemistry and Synthetic Polymers

“…41 PCL's processability allows for the formation of scaffolds composed of adhered microspheres [55,56], electrospun networks created by porogen leaching [57][58][59]. PCL and PCL composites have been used as tissue engineering scaffolds for regeneration of bone [60,61] ligament [62,63] cartilage [64], skin [65], nerve [66,67], and vascular tissues [68,69].…”