Preparation and characterization of NaF/Chitosan supramolecular complex and their effects on prevention of enamel demineralization

Alana Gail Lopes; Taís Chaves Magalhães; Ângelo Márcio Leite Denadai; Hugo Lemes Carlo; Rogério Lacerda Dos Santos; Eliseu Aldrighi Munchow; Fabíola Galbiatti de Carvalho

doi:10.1016/j.jmbbm.2023.106134

Preparation and characterization of NaF/Chitosan supramolecular complex and their effects on prevention of enamel demineralization

J Mech Behav Biomed Mater. 2023 Nov:147:106134. doi: 10.1016/j.jmbbm.2023.106134. Epub 2023 Sep 19.

Authors

Alana Gail Lopes¹, Taís Chaves Magalhães¹, Ângelo Márcio Leite Denadai¹, Hugo Lemes Carlo¹, Rogério Lacerda Dos Santos¹, Eliseu Aldrighi Munchow², Fabíola Galbiatti de Carvalho³

Affiliations

¹ Federal University of Juiz de Fora. Federal University of Juiz de Fora, Governador Valadares Campus, Juiz de Fora, Minas Gerais, Brazil.
² School of Dentistry, Federal University of Rio Grande Do Sul, Porto Alegre, Brazil.
³ Federal University of Juiz de Fora. Federal University of Juiz de Fora, Governador Valadares Campus, Juiz de Fora, Minas Gerais, Brazil. Electronic address: fabiola.galbiatti@ufjf.br.

PMID: 37742597
DOI: 10.1016/j.jmbbm.2023.106134

Abstract

Fluoridated mouthrinse is indicated for individuals with high risk of caries. Chitosan (Chit) exhibits antibacterial properties, but little is known about its effects on enamel when combined with sodium fluoride (NaF) to form NaF/Chit supramolecular complexes. In our study, NaF/Chit supramolecular complexes structured as microparticles were synthetized and characterized, and their effects on human enamel were evaluated after cariogenic challenge simulating the daily mouthrinse use. Initially, NaF/Chit complex formation was investigated based on several titrations by measuring the zeta potential, electrical conductivity (κ), hydrodynamic diameter (D_h), viscosity (η) and heat flow (by isothermal titration calorimetry) against the molar ratio [NaF]/[Chit_monomer], which allowed us to identify the interactions between Chit-NaF with a stoichiometry of approximately 0.68. Spontaneous microparticle formation was observed. Samples of enamel blocks were prepared and divided into eight groups (n = 10/group): (i) 0.2% Chit; (ii) 0.2% NaF; (iii) 0.2% NaF/Chit suspension; (iv) 0.2% acetic acid; (v) 0.05% Chit; (vi) 0.05% NaF; (vii) 0.05% NaF/Chit suspension; and (viii) 0.05% acetic acid. Cariogenic challenge was performed in each sample by cycling in demineralization and remineralization solutions for 7 days. Before each demineralization cycle, the corresponding substances were passively applied daily for 90 s, even in groups with 0.02% concentration. After 7 days, samples were examined for Knoop hardness (KHN) measurements. The data were analyzed by repeated-measures ANOVA and Tukey tests (α = 0.05). The 0.2% NaF and 0.2% NaF/Chit groups showed higher KHN_{post-challenge} values than the other groups. The 0.2% NaF/Chit microparticle suspension reduced the enamel hardness loss after cariogenic challenge as effectively as the 0.2% NaF solution and demonstrated potential for use in a formulation with anti-caries effects.

Keywords: Chitosan. sodium fluoride. supramolecular complex. anti-bacterial agents. dental caries.