Preparation On Zein/PLGA Bicomponent Nanofiber Composites

The electrospinning technique is a important method of producing nanofibers, which is a process that creates nanofibers through an electrically charged jet of polymer solution or polymer melt. The nanofibers assembly produced by electrospinning technique, due to several useful properties such as small diameter, surface area to volume ratio and high porosity, offer a wide range of applications such as tissue engineering scaffold, biosensor, drug-controlled release and filters.Zein, poly(lactic-co-glycolic acid) (PLGA) and zein/PLGA nanofibers were prepared by electrospinning in this paper. The micro-morphology of electrospinning PLGA was observed by scanning electron microscopy (SEM) firstly. PLGA was added in zein spinning solution in order to improve the mechanical properties of zein fibers and its swelling behavior in water. zein/PLGA blend fibers were produced by electrospinning. The parameters of electrospinning zein/PLGA have been studied. The microstructure of zein/PLGA fibers have been tested by means of infrared spectroscopy (FTIR) and differential scanning calorimetry (DSC). And the mechanical properties of nanofiber membranes have also been examined. Meanwhile, PLGA/zein core-shell fibers were prepared by coaxial electrospinning. The effect of the flow-rate of the inner PLGA fluid on fiber morphology was investigated. The core-shell structure of electrospinning zein/PLGA was investigated by field emission scanning electron microscopy (FE-SEM) and transmission electron microscope (TEM). The content of PLGA in PLGA/zein core-shell fiber membrane has also been measured by the way of dissolving one of the components. Finally, the mechanical properties of nanofiber membranes have also been examined.The results showed that, the solution concentration is the most significant factor influencing fiber diameter and morphology. The tensile stress and strain of the PLGA fiber membranes have been improved gradually with the solution concentration of PLGA increased. Compared with zein fiber membranes,the tensile strain and stability in water of the zein/PLGA fiber membranes have been improved effectively. When the mass ratio of zein/PLGA is 5/5, the fiber membrane shrinkage reduced to 8%. With the content of PLGA increased, the tensile stress and strain of the zein/PLGA fiber membranes have been improved when the content of zein is more than PLGA. There was no obvious interaction between zein and PLGA in the zein/PLGA blends. It's a non-homogeneous blends. Zein/PLGA fiber was a heterogeneous blend. For the zein/PLGA core-shell fiber membranes, with increasing the flow rate of inner layer, the content of PLGA increased. The results of tensile test indicated that the mechanical properties of PLGA/zein core-shell fiber membranes improved with the introduction of PLGA. Meanwhile, the tensile stress and strain of the PLGA/zein core-shell fiber membranes has been increased obviously withthe increase of the flow rate of inner layer.