Inhibition of Adherence and Biofilm Formation of Pseudomonas aeruginosa by Immobilized ZnO Nanoparticles on Silicone Urinary Catheter Grafted by Gamma Irradiation

Abstract

Nosocomial infections caused by microbial biofilm formation on biomaterial surfaces such as urinary catheters are complicated by antibiotic resistance, representing a common problem in hospitalized patients. Therefore, we aimed to modify silicone catheters to resist microbial adherence and biofilm formation by the tested microorganisms. This study used a simple direct method to graft poly-acrylic acid onto silicone rubber films using gamma irradiation to endow the silicone surface with hydrophilic carboxylic acid functional groups. This modification allowed the silicone to immobilize ZnO nanoparticles (ZnO NPs) as an anti-biofilm. The modified silicone films were characterized by FT-IR, SEM, and TGA. The anti-adherence ability of the modified silicone films was evidenced by the inhibition of biofilm formation by otherwise strong biofilm-producing Gram-positive, Gram-negative, and yeast clinical isolates. The modified ZnO NPs grafted silicone showed good cytocompatibility with the human epithelial cell line. Moreover, studying the molecular basis of the inhibitory effect of the modified silicone surface on biofilm-associated genes in a selected Pseudomonas aeruginosa isolate showed that anti-adherence activity might be due to the significant downregulation of the expression of lasR, lasI, and lecB genes by 2, 2, and 3.3-fold, respectively. In conclusion, the modified silicone catheters were low-cost, offering broad-spectrum anti-biofilm activity with possible future applications in hospital settings.

An Overview of Biofilm-Associated Infections and the Role of Phytochemicals and Nanomaterials in Their Control and Prevention

“…In such studies, methods allowing for the enhancement of biocompatibility must also be considered. Valuable advancements are associated with improving the antiadhesive and antibiofilm properties of urinary catheters coated with nanoparticles [ 121 , 122 , 123 , 124 ]. Moreover, incorporating metal and metal oxide nanoparticles into polymeric membranes is regarded as a natural approach for creating distinctive wound bandages with antibacterial and antibiofilm properties.…”

Recent Advances in Combating Bacterial Infections by Using Hybrid Nano-Systems

“…Recently, inherently antimicrobial nano-systems have been used to modify bone implants, stents, and catheters in order to prevent implant-associated infections. EVA/BS@SN ureteral J-shaped stents E. coli [186] SF/CS/Cu coating for cardiovascular stents N/A [187] PVP-AgNPs coated on silicone hydrogel E. coli [188] Nanomaterial-Modified Catheters Ag/Cu-coated catheters MRSA [189] ACPs@AgNP-coated catheter Drug resistant S. aureus [190] AgPEI NP-coated catheter Candida species [191] PDA-CMC-AgNP-coated urinary catheter E. coli, S. aureus [192] ZnO coated central venous catheter P. aeruginosa, E. coli, S. aureus [193] ZnO NP-grafted silicone catheter P. aeruginosa [194] AgNP-coated mini catheters P. aeruginosa [195] GO/CU coating C. parapsilosis [196] Ag/TiOx-PDMS nanofilm P. aeruginosa, E. coli, S. aureus [197] Nanomaterial Modified Tissue Scaffolds AgNP-silk fibroin scaffold E. coli, S. aureus [177] PCL/AgNP-coated tissue scaffold E. coli [198] Chitosan-CMC-FZO@Hap scaffold E. coli, S. paratyphi, S. aureus, & L. monocytogenes [199] Hap/AgNP-loaded cellulose scaffold E. coli, S. aureus [200] CuFe 2 O 4 -MXene/PLLA tracheal scaffold S. aureus, P. aeruginosa [201] Ag/MBG scaffold E. coli, S. aureus [202] LgNP/PCL nanofiber scaffold S. aureus [203] Antimicrobial properties and biocompatibility are crucial factors in the long-term success of titanium bone implants. Yuan et al [178] developed a nano-system for bone implants with inherently antimicrobial activity and high biocompatibility by using titanium dioxide nanotubes (TNTs or TiO 2 -NTs) loaded with AgNPs and coated with chitosan (CHI) and dialdehyde alginate (ADA) using a layer by layer (LBL) technique.…”

Antimicrobial Functionalization of Silicone-graft-poly(N-vinylimidazole) Catheters

“…Silicone films have also been modified in a two-step grafting procedure with acrylic acid and vinyl pyrrolidone silicone-g-(AAc-g-VP) [30]. Regarding silicone catheters (SC), it is possible to find reports of grafting with 2-methacryloyloxy-benzoic acid SC-g-(2MBA) [31], acrylic acid SC-g-(AAc) [32], and N-vinyl caprolactam SC-g-(NVCL) [33]. Pristine silicone may serve as the matrix for a catheter, but its surface is unable to provide antimicrobial features; adding another material on the surface can help to obtain new materials with the desired characteristics.…”

“…Silicone films have also been modified in a two-step grafting procedure with acrylic acid and vinyl pyrrolidone silicone-g-(AAc-g-VP) [30]. Regarding silicone catheters (SC), it is possible to find reports of grafting with 2-methacryloyloxy-benzoic acid SC-g-(2MBA) [31], acrylic acid SC-g-(AAc) [32], and N-vinyl caprolactam SC-g-(NVCL) [33].…”