Small diameter double layer tubular scaffolds using highly elastic PLCL copolymer for vascular tissue engineering

Abstract

Tubular double layered scaffolds were fabricated using a biodegradable and elastic polymer, poly(L-lactide-co-ε-caprolactone) (PLCL, 50:50), which was comprised of an outer fibrous gel spun layer and inner porous dip coated layer. The mechanical properties were evaluated and compared with a rabbit aorta and expanded poly-tetrafluoroethylene (ePTFE). The PLCL scaffolds had circumferentially stronger tensile stress than the rabbit aorta and ePTFE graft, and its longitudinal stress was similar to a rabbit aorta but weaker than ePTFE. The E-modulus of the PLCL scaffold was significantly lower than that of ePTFE but significantly higher than that of the native rabbit aorta, this result was reversible in the case of compliance. There was no significant difference in suture retention strength and burst pressure compared to ePTFE grafts. The scaffolds were seeded with SMCs and cultured under dynamic conditions for 13 days to evaluate the cellularity. After a 13 day dynamic culture, the scaffolds showed efficient cell proliferation. Overall, the double layer small diameter PLCL scaffolds exhibited favorable mechanical strength even at a high pressure and good cellularity under dynamic conditions.

Matching Static and Dynamic Compliance of Small‐Diameter Arteries, with Poly(lactide‐co‐caprolactone) Copolymers: In Vitro and In Vivo Studies

“…Although these studies are not directly comparable, as compliance does vary across artery type, size, species, and age,19 the high compliance mismatch between ePTFE and HFA (Figure S5b, Supporting Information) and the closer compliance matching between PLC tubes and porcine arteries (Figure S5a, Supporting Information) demonstrated here, it can be assumed the PLC tubes are considerably more elastic than ePTFE. Furthermore, it can be inferred from Figure S5a,b, Supporting Information, that the 150 µm WT tubes have a compliance similar to that recorded for an HSV 35,96,97…”

“…For the latter application, poly‐ε‐caprolactone and PLC have proven to be useful, due to their strength and rate of degradation 28–34. Moreover, the mechanical properties (e.g., elastic modulus, tensile strength, yield stress) of PLC can be fine‐tuned by adjusting the monomer ratio of l ‐lactide (LA) to ε‐caprolactone (CL), as well as the blockiness 7,29,31,35. Previous publications have shown that the tensile properties of PLC polymers are highly dependent on the monomer ratio 29,31,36…”

Elastic, double-layered poly (l-lactide-co-ϵ-caprolactone) scaffold for long-term vascular reconstruction

“…[9][10][11][12] Early thrombosis, the major cause of graft occlusion, is the principal cause of cardiovascular graft failures. 19 PLCL copolymers have been applied as a biomaterial for vascular graft applications due to their high elasticity. 2,13-16 These materials were not completely endothelialized after implantation, and pre-seeding them with endothelial cells (ECs) had limited success and did not improve the patency of the grafts.…”

“…18 In a previous study, a poly(l-lactideco-ε-caprolactone) (PLCL) scaffold had similar compliance to a native artery than PTFE did. 19 PLCL copolymers have been applied as a biomaterial for vascular graft applications due to their high elasticity. [20][21][22][23][24][25] An in situ tissue engineering approach is clinically more attractive, which involves the implantation of a cell-free scaffold.…”

Current status of three-dimensional printing inks for soft tissue regeneration

“…Despite demand for artificial tissues and organs, organ donors that can provide suitable replacements to patients are limited [7,8]. In tissue engineering, traditional scaffold fabrication methods, including electrospinning [9,10], salt-leaching [11,12], and gas foaming techniques [13,14], are very simple and sufficient to regenerate single tissues. However, these methods are limited for the fabrication of complex-shaped structures and multicellular tissues.…”