Preparation And Cytocompatibility Study Of Poly (ε-caprolactone)/silk Sericin Nanofibrous Scaffolds

Electrospinning is one of the most effective methods to produce tissue engineering scaffold materials. Scaffold which is produced by the electrospinning is similar to the natural extracellular matrix at the structural and functional and has good biocompatibility, strength and stability. It is a good way used for reconstruction of human organs.Currently, tissue engineering scaffold approach focuses on the polymer mixed. More over, electrospinning scaffold enhances the physical and biological functions by mixing artificial and natural materials. PCL was widely used for tissue engineering and drug delivery because of its good mechanical properties, biodegradability and biocompatibility. However, its use is limited by lacking of cell recognition sites and their hydrophobic property. SS is hydrophilic natural polymer protein derived from the silkworm, the main role is bonding by wrapping out of two silk fibroin. As a natural polymer with good biocompatibility, low immunogenicity, it can play the role of cytokines and other advantages.This paper is aim to produce PCL / Silk Sericin (SS) nano-3D multiporous scaffold by electrospinning, thereby to promote the interaction between cells and materials. This article contains detailed contents as follows:1. Production of nanofibrous scaffolds:Firstly, sericin protein was directly extracted from the fifth instar larvae of silkworm in vivo. Secondly, the freeze-dried sericin protein was dissolved with 9.3M LiBr. At last, sericin powder was obtained by dialysis and freeze-dried. Dissolving the freeze-dried sericin protein with HFIP as the solvent and eventually making into 5% (w / v) solution. In the mean time, 10% (w / v) of the PCL solution also was prepared with HFIP. Sericin solution was slowly added to the PCL solution to make 4 mixed solutions with different percentage of weight preparing nanofibrous scafolds by electrospinning.2. Testing of morphology and physical, chemical properties:Structure and properties were characterized by using of scanning electron microscopy (SEM),transmission electron microscopy (TEM),Fourier transform infrared spectroscopy (FTIR),contact angles and so on. The results show that the PCL / SS nanofiber scaffold containing SS nanoparticles was porous nonwoven structure and cross-linked with each other,with high uniformity and fineness of fiber diameter, and the secondary structure of SS was not changed.3. Multi-culture and observation of cells and scaffold:The adhesion and proliferation information of human skin fibroblasts (FEK4)cells on the material was observed using SEM and MTS. The results show that adhesion of the cultured cells at the nanofibers was good, and closely connected with the fiber, indicating good cellular affinity of this material. Cells in the PCL / SS fiber membrane also showed good proliferation, suggesting that the materials had no toxic to cells and suitable for cell growth.This paper demonstrated that: electrospinning PCL / SS nanofiber scaffold which is similar to the extracellular matrix structure has a good surface topology, providing a good external environment for cell adhesion and proliferation. The results provides a theoretical and experimental basis for the materials using for tissue engineering, tissue repair, wound dressings and drug delivery.