G‐CSF loaded nanofiber/nanoparticle composite coated with collagen promotes wound healing in vivo

Abstract Sustained release of functional growth factors can be considered as a beneficial methodology for wound healing. In this study, recombinant human granulocyte colony‐stimulating factor (G‐CSF)‐loaded chitosan nanoparticles were incorporated in Poly(ε‐caprolactone) (PCL) nanofibers, followed by surface coating with collagen type I. Physical and mechanical properties of the PCL nanofibers containing G‐CSF loaded chitosan nanoparticles PCL/NP(G‐CSF) and in vivo performance for wound healing were investigated. G‐CSF structural stability was evaluated through SDS_PAGE, reversed phase (RP) HPLC and size‐exclusion chromatography, as well as circular dichroism. Nanofiber/nanoparticle composite scaffold was demonstrated to have appropriate mechanical properties as a wound dresser and a sustained release of functional G‐CSF. The PCL/NP(G‐CSF) scaffold showed a suitable proliferation and well‐adherent morphology of stem cells. In vivo study and histopathological evaluation outcome revealed that skin regeneration was dramatically accelerated under PCL/NP(G‐CSF) as compared with control groups. Superior fibroblast maturation, enhanced collagen deposition and minimum inflammatory cells were also the beneficial properties of PCL/NP(G‐CSF) over the commercial dressing. The synergistic effect of extracellular matrix‐mimicking nanofibrous membrane and G‐CSF could develop a suitable supportive substrate in order to extensive utilization for the healing of skin wounds. © 2017 Wiley Periodicals Inc. J Biomed Mater Res Part A: 105A: 2830–2842, 2017.