Chitosan chemically modified to deliver nitric oxide with high antibacterial activity

Autor(es)

Pelegrino, Milena T. ^[1] ; Pieretti, Joana C. ^[1] ; Nakazato, Gerson ^[2] ; Goncalves, Marcelly Chue ^[2] ; Moreira, Jose Carlos ^[3] ; Seabra, Amedea B. ^[1]

Afiliação do(s) autor(es)

^[1] Univ Fed ABC, Ctr Nat & Human Sci, Santo Andre, SP - Brazil

^[2] Londrina State Univ UEL, Biol Sci Ctr, Dept Microbiol, Londrina, Parana - Brazil

^[3] Univ Fed ABC, Ctr Engn Modeling & Appl Social Sci, Santo Andre, SP - Brazil

• Tipo de documento: Artigo Científico
• Fonte: NITRIC OXIDE-BIOLOGY AND CHEMISTRY; v. 106, p. 24-34, JAN 1 2021.
• Citações Web of Science: 0

Resumo

The aim of the current study is to report a simple and efficient method to chemically modify chitosan in order to form S-nitroso-chitosan for antibacterial applications. Firstly, commercial chitosan (CS) was modified to form thiolated chitosan (TCS) based on an easy and environmental-friendly method. TCS was featured based on physicochemical and morphological techniques. Results have confirmed that thiol groups in TCS formed after CS's primary amino groups were replaced with secondary amino groups. Free thiol groups in TCS were nitrosated to form S-nitrosothiol moieties covalently bond to the polymer backbone (S-nitroso-CS). Kinetic measurements have shown that S-nitmso-CS was capable of generating NO in a sustained manner at levels suitable for biomedical applications. The antibacterial activities of CS, TCS and S-nitroso-CS were evaluated based on the minimum inhibitory concentration (MIC), minimum bactericidal concentration (MBC) and time-kill curves determined for Escherichia coli, Staphylococcus aureus and Streptococcus mutans. MIC/MBC values reached 25/25, 0.7/0.7 and 3.1/3.1 mu g mL(-1) for CS/TCS and 3.1/3.1, 0.1/0.2, 0.1/0.2 mu g mL(-1) for S-nitroso-CS, respectively. Decreased MIC and MBC values have indicated that S-nitroso-CS has higher antibacterial activity than CS and TCS. Time-kill curves have shown that the bacterial cell viability decreased 5-fold for E. coli and 2-fold for S. mutans in comparison to their respective controls, after 0.5 h of incubation with S-nitroso-CS. Together, CS backbone chemically modified with S-nitroso moieties have yielded a polymer capable of generating therapeutic NO concentrations with strong antibacterial effect. (AU)

• Processo FAPESP: 18/08194-2 - Óleo essencial contendo nanopartículas metálicas funcionalizadas com óxido nítrico como estratégia para o controle de patógenos vegetais na agricultura
• Beneficiário: Amedea Barozzi Seabra
• Modalidade de apoio: Auxílio à Pesquisa - Regular
• Processo FAPESP: 17/05029-8 - Preparação, caracterização e ensaios biológicos de biomateriais poliméricos doadores de óxido nítrico
• Beneficiário: Milena Trevisan Pelegrino
• Modalidade de apoio: Bolsas no Brasil - Doutorado
• Processo FAPESP: 18/02832-7 - Nanopartículas híbridas magnéticas e antibacterianas: síntese, caracterização e aplicações
• Beneficiário: Joana Claudio Pieretti
• Modalidade de apoio: Bolsas no Brasil - Mestrado