title: Shielding effect of 'surface ion pairs' on physicochemical and bactericidal properties of N,N,N-trimethyl chitosan salts.
abstract: Different methodologies were employed in this study to synthesize N,N,N-trimethyl chitosan salts (TMC). TMC free of O-methylation and with partial O-methylation were obtained and characterized through 1H nuclear magnetic resonance, wide angle X-ray scattering, scanning electron microscopy coupled with X-ray energy dispersive spectroscopy, and thermogravimetric analysis. It was verified that the dialysis process allowed the removal of 'surface ion pairs' on TMC salt structure, increasing the mobility of TMC chains. The surface ion pairs considerably increased the material crystallinity, this property being independent of the used synthesis methodology. Biological tests showed that after dialysis, TMC salts free of 'surface ion pairs' kill Escherichia coli in only 6h of incubation. So, the increase in the mobility of dialyzed TMC chains allowed a strong interaction with the cell envelope and the good bactericidal activity of TMC was enhanced.
authors.affiliation: Universidade Tecnológica Federal do Paraná (UTFPR), Estrada para Boa Esperança, CEP 85660-000 Dois Vizinhos, Paraná, Brazil; Grupo de Materiais Poliméricos e Compósitos (GMPC), Departamento de Química, Universidade Estadual de Maringá (UEM), Av. Colombo 5790, CEP 87020-900 Maringá, Paraná, Brazil. Electronic address: afmartins50@yahoo.com.br.
authors.forename: Alessandro F
authors.initials: AF
authors.lastname: Martins
authors.affiliation: Universidade Tecnológica Federal do Paraná (UTFPR), Estrada para Boa Esperança, CEP 85660-000 Dois Vizinhos, Paraná, Brazil.
authors.forename: Suelen P
authors.initials: SP
authors.lastname: Facchi
authors.affiliation: Grupo de Materiais Poliméricos e Compósitos (GMPC), Departamento de Química, Universidade Estadual de Maringá (UEM), Av. Colombo 5790, CEP 87020-900 Maringá, Paraná, Brazil.
authors.forename: Heveline D M
authors.initials: HD
authors.lastname: Follmann
authors.affiliation: Grupo de Materiais Poliméricos e Compósitos (GMPC), Departamento de Química, Universidade Estadual de Maringá (UEM), Av. Colombo 5790, CEP 87020-900 Maringá, Paraná, Brazil.
authors.forename: Adriana P
authors.initials: AP
authors.lastname: Gerola
authors.affiliation: Grupo de Materiais Poliméricos e Compósitos (GMPC), Departamento de Química, Universidade Estadual de Maringá (UEM), Av. Colombo 5790, CEP 87020-900 Maringá, Paraná, Brazil.
authors.forename: Adley F
authors.initials: AF
authors.lastname: Rubira
authors.affiliation: Grupo de Materiais Poliméricos e Compósitos (GMPC), Departamento de Química, Universidade Estadual de Maringá (UEM), Av. Colombo 5790, CEP 87020-900 Maringá, Paraná, Brazil.
authors.forename: Edvani C
authors.initials: EC
authors.lastname: Muniz
mesh_terms: D000900:Anti-Bacterial Agents / Q000737:chemistry* / Q000494:pharmacology*; D055598:Chemical Phenomena; D048271:Chitosan / Q000737:chemistry* / Q000494:pharmacology*; D004926:Escherichia coli / Q000187:drug effects; D012492:Salts / Q000737:chemistry; D013329:Structure-Activity Relationship
chemical_list: D000900:Anti-Bacterial Agents; C118071:N-trimethyl chitosan chloride; D012492:Salts; D048271:Chitosan
keywords: Bactericidal activity; Ionic pairs; N,N,N-Trimethyl chitosan; O-Methyl free TMC; O-Methylation