Silver chitosan nanocomposites as a potential treatment for superficial candidiasis

Abstract

Silver compounds are widely known for their antimicrobial activity, but can exert toxic effects to the host. Among the strategies to reduce its toxicity, incorporation into biopolymers has shown promising results. We investigated the green syntheses of silver nanoparticles (AgNPs) and their functionalization in a chitosan matrix (AgNPs@Chi) as a potential treatment against Candida spp. Inhibitory concentrations ranging between 0.06 and 1 μg/ml were observed against distinct Candida species. Nanocomposite-treated cells displayed cytoplasmic degeneration and a cell membrane and wall disruption. Silver nanocomposites in combination with fluconazole and amphotericin B showed an additive effect when analyzed by the Bliss method. The low cytotoxicity displayed in mammalian cells and in the Galleria mellonella larvae suggested their potential use in vivo. When tested as a topical treatment against murine cutaneous candidiasis, silver nanocomposites reduced the skin fungal burden in a dose-response behavior and favored tissue repair. In addition, the anti-biofilm effect of AgNPs@Chi in human nail model was demonstrated, suggesting that the polymeric formulation of AgNPs does not affect antifungal activity even against sessile cells. Our results suggest that AgNPs@Chi seems to be a less toxic and effective topical treatment for superficial candidiasis. Lay Summary This study demonstrated the efficacy of silver nanoparticles (AgNPs) in inhibiting the growth of Candida. AgNPs incorporated in chitosan displayed a reduced toxicity. Tests in infected mice showed the effectiveness of the treatment. AgNPs-chitosan could be an alternative to combat candidiasis.

Biogenic Synthesis of Chitosan/Silver Nanocomposite by Escherichia coli D8 (MF062579) and its Antibacterial Activity

“…AgNPs have been stabilized using CS in numerous investigations (Marková et al, 2012;El-Sherbiny and Sedki, 2019;Bonilla et al, 2021). AgNPs are tightly connected to the CS OH groups, forming a network of polymeric chains that reduces NP aggregation and boosts stability (Kumar, 2000).…”

Scaffolds in the microbial resistant era: Fabrication, materials, properties and tissue engineering applications

“…The cytotoxicity studies carried out on antifungal scaffolds for tissue engineering are included in Table 5 . Scaffolds for skin regeneration that include antifungal properties based on the incorporation of antibiotics, metals, peptides and also the use of antimicrobial polymers have been assessed using mainly human [ 383 ] or murine fibroblasts [ 383 , 393 , 397 ]. Biocompatibility studies of scaffolds based on PLC/TiO 2 /cefuroxime for cornea regeneration were performed with human limbal stem cells [ 392 ], which showed good behavior regarding cell adhesion, proliferation, and differentiation.…”

“…The scaffold showed effective antifungal behavior in an in vivo study (mouse model) as well as good biocompatibility [ 395 ], indicating a good potential for wound healing. Cytotoxicity studies were carried out on general-purpose antifungal scaffolds for tissue engineering using several cell lines such as MSCs [ 390 ], fibroblasts [ 360 , 393 ], human endothelial cells, human carcinoma cells [ 389 ] and human endothelial cells [ 394 ], although biocompatibility assays were not reported in several studies [ 384 , 385 , 387 , 388 , 391 , 396 , 398 ].…”

Hyaluronic Acid-Silver Nanocomposites and Their Biomedical Applications: A Review

“…Moreover, nanosilver exhibits a broad spectrum of antifungal activity. In the combination with fungicides, such as amphotericin B and fluconazole, the effectiveness increases [ 59 , 60 ].…”