Effect of chitosan nanoparticles on the inhibition of Candida spp. biofilm on denture base surface

Publication date: Available online 9 July 2018

Source: Archives of Oral Biology

Author(s): Brenna Louise Cavalcanti Gondim, Lúcio Roberto Cançado Castellano, Ricardo Dias de Castro, Giovanna Machado, Hugo Lemes Carlo, Ana Maria Gondim Valença, Fabíola Galbiatti de Carvalho

Abstract

Objectives

Chitosan nanoparticles (ChNPs) have antifungal effects, however there is a lack of information about the effects of ChNPs against Candida biofilm on denture base surface. This study investigated the ChNPs effect against C. albicans biofilm adhesion and formation, and against Candida spp. biofilm on heat-cured acrylic resin.

Design

The ChNPs were synthetized (3,800 µg/mL) and characterized by infra-red spectrophotometry and transmission electron microscopy. The minimum inhibitory/fungicidal concentrations (MIC/MFC) against Candida spp. were determined. The time-kill assay and changes on C. albicans micromorphology were evaluated. The % inhibition of ChNPs on C. albicans biofilm formation and reduction were investigated using 1 min and 8 h exposure. Candida biofilm was developed on resin surfaces and ChNPs were applied every 8 h for 5 days. After, fungal cells were counted (CFU/mL) and the surface roughness (Ra) and vickers microhardness (HV) of resin were analysed. For all experiments, sodium hypochlorite (NaOCl) was used as control. Data were analyzed by ANOVA, Tukey and paired t-tests (α = 0.05).

Results

The MIC_80% of ChNPs was 30.1 µg/mL. ChNPs at 4 MIC showed complete inhibition in the time-kill assays. Blastoconidia cells were predominant after ChNPs application. The % inhibition ChNPs on C. albicans was proportional to its concentration, regardless of the exposure time. ChNPs decreased the CFU/mL of Candida spp. and showed lower alteration of HV and Ra values of resin surface compared to NaOCl.

Conclusions

The ChNPs inhibited C. albicans biofilm, reduced Candida biofilm on resin and caused small changes in roughness and hardness of acrylic resin surface.

Graphical abstract

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