Study on the Synthesis and Practical Application of Chitosan-silver Nanoparticles Targeting Pseudomonas Aeruginosa Biofilms

YU Guo-he; LIN Wen-hong; LIANG Hai-ying; LIN Mei-ling

Abstract：Objective: To develop chitosan-silver nanoparticles targeting Pseudomonas aeruginosa biofilms and verify their antibacterial performance through animal experiments. Methods: Chitosan, silver nitrate, glacial acetic acid, and other chemical reagents were used to synthesize chitosan-silver nanoparticles. The characterization, minimum inhibitory concentration, and biofilm inhibition rate of the chitosan-silver nanoparticles were tested. A total of 40 SD rats were randomly divided into four groups. After routine adaptive feeding, the control group received intraperitoneal injection of normal saline; the model group received intraperitoneal injection of Pseudomonas aeruginosa suspension; the positive group received intraperitoneal injection of Pseudomonas aeruginosa suspension mixed with ampicillin at a volume ratio of 1∶1; the observation group received intraperitoneal injection of Pseudomonas aeruginosa suspension mixed with chitosan-silver nanoparticles (at minimum inhibitory concentration) at a volume ratio of 1∶1. Bacterial load, inflammatory factors, and liver and kidney function indicators in tissues were observed and compared among the four groups on the 3rd day after treatment. Results: When the concentration of chitosan-silver nanoparticles reached 8 μg/mL or above, the OD value of the experimental wells was close to that of the control wells, indicating that 8 μg/mL was the minimum inhibitory concentration of the chitosan-silver nanoparticles; at concentrations of 8 μg/mL or above, the biofilm inhibition rate was greater than 80%. The bacterial load in the observation group was significantly lower than that in the model and positive groups (P<0.05). The expression levels of interleukin-6, interferon-γ, and tumor necrosis factor-α in the observation group were significantly lower than those in the model and positive groups (P<0.05). There were no statistically significant differences in alanine aminotransferase, aspartate aminotransferase, blood urea nitrogen, and creatinine levels among the four groups (P>0.05). Conclusion: The chitosan-silver nanoparticles targeting Pseudomonas aeruginosa biofilms constructed in this study exhibit good antibacterial effects against Pseudomonas aeruginosa and have good safety.