Preparation and properties of polylactic acid (PLA) antibacterial nanofiber membrane with Ag@TP composite antibacterial agent

This paper presented the composite antibacterial agent of nano-silver (Ag) and tea polyphenol (TP) by bioreduction method. Then polylactic acid (PLA) nanofiber membranes with different antibacterial content were prepared by electrostatic spinning method. The morphologies, structural characteristics and properties of electrostatic spun fiber membranes were investigated by scanning electron microscope (SEM), infrared spectroscopy (FTIR), electronic single fiber strength machine and flat colony counting method. The results showed that Ag@TP was loaded with silver nanoparticles with uniform particle size distribution. When the content of Ag@TP of electrospun fiber was less than 2.0%, the diameter of electrostatic spinning fiber was uniformly distributed and had smooth surface. It could be seen from the FTIR spectrum that Ag@TP and PLA were well compounded through valence bonds. As the content of antibacterial agent increased, the elongation at break of the fiber membrane first decreased and then increased. While the breaking strength was found to first decrease, then increase and decrease again. The water contact angle of the fiber membrane was gradually decreased with the increase of the antibacterial agent content. When the amount of Ag@TP was added 2.0%, the relative antibacterial rate of the electrospun fiber membrane to E.coli and S.aureus was as high as 95%, indicating an excellent antibacterial effect.