Banca de QUALIFICAÇÃO: RAFAELA GOMES BEZERRA

Uma banca de QUALIFICAÇÃO de DOUTORADO foi cadastrada pelo programa.
STUDENT : RAFAELA GOMES BEZERRA
DATE: 05/05/2025
TIME: 14:00
LOCAL: Qualificação por acesso remoto
TITLE:

Zein nanoparticles loaded with arginine-derived cationic surfactants: development, characterization and biopharmaceutical and microbiological evaluation against oral biofilms

KEY WORDS:

Surfactant; Arginine; Antimicrobial; Nanoparticle; Zein;
Dentistry.

PAGES: 80
BIG AREA: Ciências Biológicas
AREA: Farmacologia
SUMMARY:

Introduction: Microbial resistance to traditional antimicrobials has led to the search for innovative alternatives, especially in Dentistry, where biofilms present in the oral cavity are associated with several pathologies. Arginine-derived cationic surfactants (ARDS) stand out for their great efficacy against resistant biofilms. This action is enhanced when combined with zein nanoparticles (NPs), a biocompatible and sustainable delivery system that enables controlled in situ release, expanding its antimicrobial spectrum and reducing tissue toxicity. Objective: To develop, characterize and evaluate the antimicrobial and biopharmaceutical properties of delivery systems based on zein NPs loaded with arginine-derived cationic surfactants. Methodology: The antimicrobial activity of the surfactants LAM, LAE, LANHC 3 , LANHC 5 and LANHC 8 was evaluated on planktonic cells and biofilms of Staphylococcus aureus, Staphylococcus epidermidis, Streptococcus mutans, Streptococcus pyogenes, Enterococcus faecalis, Escherichia coli, Pseudomonas aeruginosa, Candida albicans, Candida krusei, Candida parapsilosis and Candida tropicalis. The modulating capacity on antimicrobials for clinical use was evaluated by the checkerboard method, while their antioxidant activity was evaluated by the elimination of DPPH radicals. The NPs were developed through different preparation techniques with the surfactants that presented the best performance in the previous steps. The particle size, zeta potential (PZ) and polydispersity index (PDI) were measured. Their antimicrobial, modulating and antioxidant activity, as well as their cytotoxicity against fibroblasts, were then evaluated. Results and discussion: The surfactants LAM and LANHC 3 showed the best results in the microbiological evaluation, mainly regarding the modulating potential on chlorhexidine, and were used for the development of NPs. The characterization indicated the most effective preparation methodology and whether there was a difference between surfactants. The study will continue with biopharmaceutical evaluation, in order to enable the application of these nanoformulations for the prevention and treatment of oral biofilms. Conclusions: The results obtained are promising and suggest that cationic surfactants derived from arginine, in addition to being biodegradable, when nanoencapsulated, may benefit from greater stability, selectivity and biocompatibility, and may assist in the prevention and/or treatment of pathologies associated with the presence of oral biofilms.

COMMITTEE MEMBERS:
Presidente - 1924165 - FRANCISCO FABIO OLIVEIRA DE SOUSA
Interno - 1867989 - IRLON MACIEL FERREIRA
Externa à Instituição - RAMILLE ARAUJO LIMA