Chitosan chemically modified to deliver nitric oxide with high antibacterial activity.
Nitric Oxide
; 106: 24-34, 2021 01 01.
Article
en En
| MEDLINE
| ID: mdl-33098968
ABSTRACT
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-nitroso-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 µg mL-1 for CS/TCS and 3.1/3.1, 0.1/0.2, 0.1/0.2 µg 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.
Palabras clave
Texto completo:
1
Colección:
01-internacional
Base de datos:
MEDLINE
Contexto en salud:
3_ND
Problema de salud:
3_neglected_diseases
/
3_zoonosis
Asunto principal:
Donantes de Óxido Nítrico
/
Quitosano
/
Antibacterianos
/
Óxido Nítrico
/
Compuestos Nitrosos
Idioma:
En
Revista:
Nitric Oxide
Asunto de la revista:
BIOQUIMICA
/
QUIMICA
Año:
2021
Tipo del documento:
Article
País de afiliación:
Brasil