title: Factorial design optimization and in vivo feasibility of poly(epsilon-caprolactone)-micro- and nanofiber-based small diameter vascular grafts.
abstract: Because of the severe increase of mortality by cardiovascular diseases, there has been rising interest among the tissue-engineering community for small-sized blood vessel substitutes. Here we present small diameter vascular grafts made of slow degradable poly(epsilon-caprolactone) nanofibers obtained by electrospinning. The process was optimized by a factorial design approach that led to reproducible grafts with inner diameters of 2 and 4 mm, respectively. Fiber sizes, graft morphology, and the resulting tensile stress and tensile strain values were studied as a function of various parameters in order to obtain optimal vascular grafts for implantation after gamma-sterilization. The influence of polymer concentration, solvent, needle-collector distance, applied voltage, flow rate, and spinning time has been studied. Consequently, an optimized vascular graft was implanted as an abdominal aortic substitute in nine rats for a feasibility study. Results are given following up a 12-week implantation period showing good patency, endothelization, and cell ingrowth.
authors.affiliation: Department of Pharmaceutics and Biopharmaceutics, School of Pharmaceutical Sciences, University of Geneva, University of Lausanne, Geneva 1211, Switzerland.
authors.forename: B
authors.initials: B
authors.lastname: Nottelet
authors.forename: E
authors.initials: E
authors.lastname: Pektok
authors.forename: D
authors.initials: D
authors.lastname: Mandracchia
authors.forename: J-C
authors.initials: JC
authors.lastname: Tille
authors.forename: B
authors.initials: B
authors.lastname: Walpoth
authors.forename: R
authors.initials: R
authors.lastname: Gurny
authors.forename: M
authors.initials: M
authors.lastname: Möller
mesh_terms: D000792:Angiography; D000818:Animals; D001807:Blood Vessel Prosthesis; D001808:Blood Vessels / Q000166:cytology / Q000637:transplantation* / Q000648:ultrastructure; D005240:Feasibility Studies; D020007:Implants, Experimental; D049329:Nanostructures / Q000737:chemistry*; D010865:Pilot Projects; D011091:Polyesters / Q000494:pharmacology*; D051381:Rats; D012997:Solvents; D013499:Surface Properties / Q000187:drug effects; D013718:Tensile Strength / Q000187:drug effects; D023822:Tissue Engineering / Q000379:methods*
chemical_list: D011091:Polyesters; D012997:Solvents; C016240:polycaprolactone