Preparation And Performance Of Microbial-loaded Antibacterial Hydrogel

As a kind of super absorbent and water-retaining material,hydrogel is used in many fields.In terms of medical treatment,the three-dimensional network structure of hydrogel and its rich functional groups make it possess the performance of drug loading and controlled release.This performance can be used for reference in the preparation of antibacterial hydrogel,the corresponding antibacterial hydrogels will be obtained.Most of the antibacterial materials of hydrogels load antibacterial agents on the hydrogel substrate to achieve the antibacterial purpose.As a probiotic,Lactobacillus acidophilus is one of the natural antibacterial agents,it has a wide range of sources and can be regenerated,in addition to lactic acid,acetic acid and diacetyl in the fermentation process,it can also produce bacteriocin antibacterial substances,so Lactobacillus acidophilus has potential as an antibacterial agent.Therefore,it is prepared as a new antibacterial hydrogel with antibacterial properties in anticipation of good antibacterial applications.(1)By simple physical blending of WPU and PVA,SA and PVA,two hydrogen-bonded cross-linked two hydrogels could be prepared by circulating freezing without adding cross-linking agent.The two hydrogel materials were macroporous materials,with pore diameters far greater than 50 nm and reaching the micron level,scanning electron microscopy observation and swelling ratio porosity test showed that the three-dimensional cavity structure was the best when the volume ratio of WPU,SA and PVA was 1:2,therefore,the size of the three-dimensional pore structure could be controlled by controlling the ratio of WPU/PVA and SA/PVA.Compared with the raw material,the hydrogel material had improved crystallization performance,and the higher the PVA content,the better the crystallization performance.(2)RG-WPU/PVA and RG-WPU/PVA hydrogels loaded with Lactobacillus acidophilus as antibacterial agent were prepared by immersion loading method.The optimization of the loading conditions of the hydrogel showed that the RG-WPU/PVA hydrogel had a soaking time of 10 h,a temperature of 31?,pH=3,a hydrogel raw material volume ratio of 1:2,and a gel mass of 2.5 g.The concentration of the solution is 1×108 cfu/mL,the volume of the bacterial solution is 30 mL,the RG-SA/PVA hydrogel was soaked for 10 h,the temperature was 31?,pH=3,and the volume ratio of the raw material volume of the hydrogel was 1:2.The gel mass 2 g bacterial solution concentration was 1×108 cfU/mL.When the bacterial solution volume was 30 mL,the maximum bacterial load and bacterial load rate could be maximized without causing waste of bacterial solution and energy.Scanning electron microscope and infrared tests could see that the network structure of the hydrogel had not changed and no new peaks have been generated.Therefore,the attachment of Lactobacillus acidophilus to the surface of the gel did not affect its pore structure and chemical structure.Combined with the Zeta potential test,The zero point potential of RG-WPU/PVA and RG-WPU/PVA hydrogels were shifted to 2.7 and 2.1 respectively,indicating that there was hydrogen bonding between the cells and the material and the effect of electrostatic force;the thermogravimetric curve indicates that the two The decomposition temperature of the hydrogel increased by about 20?,and the load of bacteria could improve the thermal stability of the hydrogel,but the crystallization performance was reduced.(3)The release process of bacteria-containing hydrogel was a rapid process,both kinds of hydrogels could reach the equilibrium of the release of bacteria within 25 minutes.The release of the RG-WPU/PVA?RG-WPU/PVA hydrogels under the temperature factor conformed to the Peppas release model,and the process was divided into irregular diffusion and Fick diffusion with the boundaries of 31? and 34?.Under pH,the bacteria release process of RG-WPU/PVA hydrogel belonged to erosion and diffusion.The bacteria released by RG-SA/PVA hydrogel belonged to erosion and diffusion during the first 10 minutes,and RG-SA/PVA hydrocoagulates after 10 minutes the release of gelatinous bacteria belonged to erosion and diffusion when the pH was less than 5,and did not meet the Peppas release model after the pH was greater than 6.(4)Through the inhibition zone experiment and bacteriostatic efficiency experiment,the higher the concentration of Lactobacillus acidophilus,the better the bacteriostatic effect.The bacteriostatic effect of Lactobacillus acidophilus on Staphylococcus was better than that of E.coli.The minimum inhibitory concentrations were 1.7×104 cfu/mL,1.7×105 cfu/mL.The continuous reproduction of Lactobacillus acidophilus has been secreted by the product and it has good antibacterial persistence.The culture of bacteria at different pH showed that the bacteria could survive in the environment of pH=3 to pH=10.After the bacteria-containing antibacterial hydrogel was successfully prepared,it should be stored in freeze-drying or vacuum.