title: New poly(ester urea) derived from L-leucine: electrospun scaffolds loaded with antibacterial drugs and enzymes.
abstract: Electrospun scaffolds from an amino acid containing poly(ester urea) (PEU) were developed as promising materials in the biomedical field and specifically in tissue engineering applications. The selected poly(ester urea) was obtained with a high yield and molecular weight by reaction of phosgene with a bis(α-aminoacyl)-α,ω-diol-diester monomer. The polymer having L-leucine, 1,6-hexanediol and carbonic acid units had a semicrystalline character and relatively high glass transition and melting temperatures. Furthermore it was highly soluble in most organic solvents, an interesting feature that facilitated the electrospinning process and the effective incorporation of drugs with bactericidal activity (e.g. biguanide derivatives such as clorhexidine and polyhexamethylenebiguanide) and enzymes (e.g. α-chymotrypsin) that accelerated the degradation process. Continuous micro/nanofibers were obtained under a wide range of processing conditions, being diameters of electrospun fibers dependent on the drug and solvent used. Poly(ester urea) samples were degradable in media containing lipases and proteinases but the degradation rate was highly dependent on the surface area, being specifically greater for scaffolds with respect to films. The high hydrophobicity of new scaffolds had repercussions on enzymatic degradability since different weight loss rates were found depending on how samples were exposed to the medium (e.g. forced or non-forced immersion). New scaffolds were biocompatible, as demonstrated by adhesion and proliferation assays performed with fibroblast and epithelial cells.
authors.affiliation: Departament d'Enginyeria Química, Universitat Politècnica de Catalunya, Av. Diagonal 647, Barcelona E-08028, Spain.
authors.forename: Angélica
authors.initials: A
authors.lastname: Díaz
authors.affiliation: Departament d'Enginyeria Química, Universitat Politècnica de Catalunya, Av. Diagonal 647, Barcelona E-08028, Spain.
authors.forename: Luis J
authors.initials: LJ
authors.lastname: del Valle
authors.affiliation: Institute of Chemistry and Molecular Engineering, Agricultural University of Georgia, 13km. David Aghmashenebeli Alley, Tblisi 0131, Georgia.
authors.forename: David
authors.initials: D
authors.lastname: Tugushi
authors.affiliation: Institute of Chemistry and Molecular Engineering, Agricultural University of Georgia, 13km. David Aghmashenebeli Alley, Tblisi 0131, Georgia.
authors.forename: Ramaz
authors.initials: R
authors.lastname: Katsarava
authors.affiliation: Departament d'Enginyeria Química, Universitat Politècnica de Catalunya, Av. Diagonal 647, Barcelona E-08028, Spain. Electronic address: Jordi.Puiggali@upc.edu.
authors.forename: Jordi
authors.initials: J
authors.lastname: Puiggalí
mesh_terms: D000900:Anti-Bacterial Agents / Q000008:administration & dosage* / Q000494:pharmacology; D002448:Cell Adhesion / Q000187:drug effects; D049109:Cell Proliferation / Q000187:drug effects; D004798:Enzymes / Q000008:administration & dosage* / Q000494:pharmacology; D004926:Escherichia coli / Q000187:drug effects; D007930:Leucine / Q000737:chemistry*; D008826:Microbial Sensitivity Tests; D016982:Micrococcus luteus / Q000187:drug effects; D008855:Microscopy, Electron, Scanning; D011091:Polyesters / Q000737:chemistry*; D014508:Urea / Q000737:chemistry*
chemical_list: D000900:Anti-Bacterial Agents; D004798:Enzymes; D011091:Polyesters; D014508:Urea; D007930:Leucine
keywords: Biguanide; Biocompatibility; Drug release; Electrospinning; Enzymatic degradation; Poly(ester urea); Scaffold; l-Leucine