Preparation And Performance Of Poly(ε-caprolactone)/γ-poly(glutamic Acid) Electrospun Fibrous Membranes For Drug Release

Electrospinning is a versatile polymer processing technique which plays an important part in both research and production of medical, food, protection, filtering,photoelectric areas due to its advantages of high porosity,big length-diameter ratio,high fiber uniformity and surface area to volume ratio. Especially in medical areas,electrospun polymer membranes can be implanted in organisms used for tissue scaffolds, tissue repair,cell carrier and mimicking the extracellular matrix, etc.Electrospinng affords great flexibility in selecting materials for drug control-released carrier applications. Furthermore, the biodegradability of polymer carrier can delay the action time of drugs in organisms and decreasing dosing frequency. In this research,we blended Poly(ε-caprolactone)(PCL) and γ-Poly(glutamic acid)(γ-PGA)in hexafluoroisopropanol(HFIP) with different ratios, and studied the properties of PCL/γ-PGA electrospun fibrous membranes. Also, we electrospun drug loaded fibrous membranes with florfenicol(FF) and studied the drug release behavior of the FF-PCL/γ-PGA drug loaded electrospun nanofibrous membranes.Scanning electron microscopy(SEM) images revealed the morphology of the electrospun fibers, the results show that the diameter of the electrospun PCL/γ-PGA fibers was increasing with the increasing of blend solution concentration, with decreasing of the γ-PGA content and increasing of the FF content. The film-forming property and fiber uniformity were good when the voltage was 15 kV, PCL/γ-PGA ratio less than 85/15, FF content less than 1.5% and blend solution concentration less than 10%. Fourier transform infrared spectroscopy(FTIR) and differential scanning calorimetry(DSC) showed that there existed weak interaction between the two components PCL and γ-PGA,and FF did exist in the drug delivery. Since there were no obvious FF drug crystal existing in the SEM images,we may suggest that some of the FF drugs were wrapped in the PCL/γ-PGA electrospun nanofibers and others were blended with PCL/γ-PGA system. Tensile tests showed both PCL/γ-PGA electrospun nanofibrous membranes and FF-PCL/γ-PGA drug loaded electrospun nanofibrous membranes had certain mechanical properties. Elastic deformation ability of PCL/γ-PGA electrospun nanofibrous membranes increased with the increasing ofγ-PGA content, and Elastic deformation ability of FF-PCL/γ-PGA drug loaded electrospun nanofibrous membranes decreased with the increasing of FF drug content.The results of water contact tests showed that pure PCL electrospun nanofibrous membrane was hydrophobic,both PCL/γ-PGA electrospun nanofibrous membranes and FF-PCL/γ-PGA drug loaded electrospun nanofibrous membranes were hydrophilic. Which demonstrated γ- PGA effective improved the hydrophilicity of PCL.The results of FF-PCL/γ-PGA drug loaded electrospun nanofibrous membranes drug release research showed that the FF-PCL/γ-PGA as a carrier effectively improved the solubility of FF and FF-PCL/γ-PGA drug loaded electrospun nanofibrous membranes with different ratios all could control the drug release. The accumulative drug release rate of FF could be 60%-80% in 47 h. The first 4 hours of the drug release was burst release phase which release rate was fast and the accumulative drug release rate was over 30%, after that the release rate was slower and slower. Drug release process of pure drug-loaded PCL electrospun nanofibrous membrane was mainly determined by the diffusion of FF, and drug release process of FF-PCL/γ-PGA drug loaded electrospun nanofibrous membranes was co-determined by the drug diffusion and the dissolve corrosion mechanism of the fiber surface. The accumulative drug release rate of FF-PCL/γ-PGA drug loaded electrospun nanofibrous membranes was increasing with the increasing of the γ-PGA proportion and FF content.