Effects of antifungal carriers based on chitosan-coated iron oxide nanoparticles on microcosm biofilms

Caldeirão, A. C. M., Araujo, H. C., Tomasella, C. M., Sampaio, C., dos Santos Oliveira, M. J., Ramage, G. , Pessan, J. P. and Monteiro, D. R. (2021) Effects of antifungal carriers based on chitosan-coated iron oxide nanoparticles on microcosm biofilms. Antibiotics, 10(5), 588. (doi: 10.3390/antibiotics10050588) (PMID:34067527) (PMCID:PMC8155828)

Abstract

Resistance of Candida species to conventional therapies has motivated the development of antifungal nanocarriers based on iron oxide nanoparticles (IONPs) coated with chitosan (CS). This study evaluates the effects of IONPs-CS as carriers of miconazole (MCZ) or fluconazole (FLZ) on microcosm biofilms. Pooled saliva from two healthy volunteers supplemented with C. albicans and C. glabrata was the inoculum for biofilm formation. Biofilms were formed for 96 h on coverslips using the Amsterdam Active Attachment model, followed by 24 h treatment with nanocarriers containing different concentrations of each antifungal (78 and 156 µg/mL). MCZ or FLZ (156 µg/mL), and untreated biofilms were considered as controls. Anti-biofilm effects were evaluated by enumeration of colony-forming units (CFUs), composition of the extracellular matrix, lactic acid production, and structure and live/dead biofilm cells (confocal laser scanning microscopy-CLSM). Data were analyzed by one-way ANOVA and Fisher LSD’s test (α = 0.05). IONPs-CS carrying MCZ or FLZ were the most effective treatments in reducing CFUs compared to either an antifungal agent alone for C. albicans and MCZ for C. glabrata. Significant reductions in mutans streptococci and Lactobacillus spp. were shown, though mainly for the MCZ nanocarrier. Antifungals and their nanocarriers also showed significantly higher proportions of dead cells compared to untreated biofilm by CLSM (p < 0.001), and promoted significant reductions in lactic acid, while simultaneously showing increases in some components of the extracellular matrix. These findings reinforce the use of nanocarriers as effective alternatives to fight oral fungal infections.

• Item Type: Articles
• Additional Information: Funding: This research was funded by São Paulo Research Foundation (FAPESP, Brazil; grant number 2017/24416-2), Coordenação de Aperfeiçoamento de Pessoal de Nível Superior (CAPES, Brazil; Finance Code 001), and Conselho Nacional de Desenvolvimento Científico e Tecnológico (CNPq, Brazil; scholarship for C.M.T.).
• Status: Published
• Refereed: Yes
• Glasgow Author(s) Enlighten ID: Ramage, Professor Gordon

Creator Roles

Ramage, G.: Formal analysis, Investigation, Writing – review and editing

• Authors: Caldeirão, A. C. M., Araujo, H. C., Tomasella, C. M., Sampaio, C., dos Santos Oliveira, M. J., Ramage, G., Pessan, J. P., and Monteiro, D. R.
• College/School: College of Medical Veterinary and Life Sciences > School of Medicine, Dentistry & Nursing > Dental School
• Journal Name: Antibiotics
• Publisher: MDPI
• ISSN: 2079-6382
• ISSN (Online): 2079-6382
• Published Online: 17 May 2021
• Copyright Holders: Copyright © 2021 by the authors
• First Published: First published in Antibiotics 10(5):e588
• Publisher Policy: Reproduced under a Creative Commons Licence