title: Electrospun blends of gelatin and gelatin-dendrimer conjugates as a wound-dressing and drug-delivery platform.
abstract: In this work, we report a new nanofiber construct based on electrospun blends of gelatin and gelatin-dendrimer conjugates. Highly branched star-shaped polyamidoamine (PAMAM) dendrimer G3.5 was covalently conjugated to gelatin via EDC/NHS chemistry. Blends of gelatin and gelatin-dendrimer conjugates mixed with various loading levels of silver acetate (0, 0.83, 1.65, and 3.30% w/w) were successfully electrospun into nanofiber constructs (NCs). The NCs were further converted into semi-interpenetrating networks (sIPNs) with photoreactive polyethylene glycol diacrylate (Mn = 575 g mol(-1)) (PEG DA575). They were characterized in terms of fiber morphology, diameter, pore size, permeability, degradation, and mechanical properties. The resulting sIPN NCs retained nanofiber morphology, possessed similar fiber diameters to counterpart NCs, and gained improved structural stability. The sIPN NCs also showed good swelling capacity owing to porous structures and were permeable to aqueous solutions. Silver-containing sIPN NCs allowed sustained silver release and showed antimicrobial activity against two common types of pathogens, Staphylococcus aureus and Pseudomonas aeruginosa. Incorporation of dendrimers into the gelatin nanofibers through covalent conjugation not only expands drug loading capacity of nanofiber constructs but also provides tremendous flexibility for developing multifunctional electrospun dressing materials.
authors.affiliation: Department of Biomedical Engineering, Virginia Commonwealth University , 401 West Main Street, Richmond, Virginia 23284, United States.
authors.forename: Alpana A
authors.initials: AA
authors.lastname: Dongargaonkar
authors.forename: Gary L
authors.initials: GL
authors.lastname: Bowlin
authors.forename: Hu
authors.initials: H
authors.lastname: Yang
mesh_terms: D000900:Anti-Bacterial Agents / Q000032:analysis / Q000737:chemistry / Q000494:pharmacology*; D001458:Bandages; D001672:Biocompatible Materials / Q000737:chemistry; D050091:Dendrimers / Q000737:chemistry*; D016503:Drug Delivery Systems; D005780:Gelatin / Q000737:chemistry*; D007700:Kinetics; D008826:Microbial Sensitivity Tests; D015394:Molecular Structure; D016062:Porosity; D011550:Pseudomonas aeruginosa / Q000187:drug effects; D012834:Silver / Q000032:analysis / Q000737:chemistry / Q000494:pharmacology; D013211:Staphylococcus aureus / Q000187:drug effects; D014945:Wound Healing / Q000187:drug effects
chemical_list: D000900:Anti-Bacterial Agents; D001672:Biocompatible Materials; D050091:Dendrimers; C104700:PAMAM Starburst; D012834:Silver; D005780:Gelatin