Calorimetric studies of the action of chitosan-N-2-hydroxypropyl trimethyl ammonium chloride on the growth of microorganisms

Qin, Caiqin; Xiao, Qi; Li, Huirong; Fang, Mu; Liu, Yi; Chen, Xin-You; Li, Qiang

doi:10.1016/j.ijbiomac.2004.03.009

Cited by 163 publications

(47 citation statements)

References 17 publications

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“…Chitosan, which is a deacetylated form of chitin, has been investigated for numerous antimicrobial activities. In particular, water-soluble chitosan derivatives were evaluated for their antimicrobial activity [59]. The actual mechanism of antimicrobial activity of chitosan and its derivatives is not yet fully understood but has been suggested to involve cell lysis, breakdown of the cytoplasmic membrane barrier and the chelation of trace metal cations by the chitosan [60–64].…”

Section: Antimicrobial Effectsmentioning

confidence: 99%

Applications of Chitin and Its Derivatives in Biological Medicine

Park

Kim

2010

IJMS

313

166

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Chitin and its derivatives—as a potential resource as well as multiple functional substrates—have generated attractive interest in various fields such as biomedical, pharmaceutical, food and environmental industries, since the first isolation of chitin in 1811. Moreover, chitosan and its chitooligosaccharides (COS) are degraded products of chitin through enzymatic and acidic hydrolysis processes; and COS, in particular, is well suited for potential biological application, due to the biocompatibility and nontoxic nature of chitosan. In this review, we investigate the current bioactivities of chitin derivatives, which are all correlated with their biomedical properties. Several new and cutting edge insights here may provide a molecular basis for the mechanism of chitin, and hence may aid its use for medical and pharmaceutical applications.

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Section: Antimicrobial Effectsmentioning

confidence: 99%

Applications of Chitin and Its Derivatives in Biological Medicine

Park

Kim

2010

IJMS

313

166

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“…As amostras foram filtradas e secas e os espectros de EDX foram obtidos. [13][14][15] . Os espectros de RMN de 13 C e 1 H, também apresentaram diferenças marcantes entre o SAQQ e a quitosana.…”

Section: Espectr Espectr Espectr Espectr Espectrometria De Ener Ometrunclassified

“…Os espectros de RMN de 13 C e 1 H, também apresentaram diferenças marcantes entre o SAQQ e a quitosana. Os espectros RMN de 13 C e 1 H apresentaram um sinal em 54,7 ppm e em 3,25 ppm, respectivamente e características das metilas no grupo amônio, ausentes no polímero original [13,14,16,17] . A quantidade dos grupos quaternários foi determinada por titulação condutimétrica dos íons cloreto usando uma solução padrão de AgNO 3 .…”

Section: Espectr Espectr Espectr Espectr Espectrometria De Ener Ometrunclassified

Cinética e equilíbrio de adsorção dos oxiânions Cr (VI), Mo (VI) e Se (VI) pelo sal de amônio quaternário de quitosana

et al. 2005

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Resumo: O sal quaternário de quitosana foi sintetizado com cloreto de glicidil trimetil amônio. A modificação química foi caracterizada por espectrometria no IV, RMN de 13 C e 1 H, e mmol/g de grupos quaternários presentes na matriz polimérica por condutimetria. A remoção de Cr (VI), Mo (VI) e Se (VI), em meio aquoso, foi investigada em processo de batelada. A adsorção mostrou ser dependente do pH para o Cr (VI) e Se (VI), com um pH ótimo de adsorção, entre 4,0 a 6,0. Para o Mo (VI) a adsorção manteve-se quase constante no intervalo de pH entre 4,0 e 11,5. O modelo de isoterma de Langmuir descreveu melhor os dados de equilíbrio na faixa de concentração investigada. No presente estudo, um grama do sal quaternário de quitosana reticulado com glutaraldeído adsorveu 68,3 mg de Cr, 63,4 mg de Mo e 90,0 mg de Se. A velocidade de adsorção, no processo, segue a equação cinética de pseudo segunda-ordem, sendo que o equilíbrio para os três íons foi alcançado próximo aos 200 minutos. A análise dispersiva de raios-X para o Cr (VI) mostrou que o principal mecanismo de adsorção é a troca iônica entre os íons Cl -da superfície do polímero pelos oxiânions. O trocador aniônico apresentou a seguinte ordem de seletividade: Cr (VI) > Mo (VI) > Se (VI). Palavras-chave: Adsorção, cromo (VI), molibdênio (VI), selênio (VI), sal quaternário de quitosana. Kinetics and Equilibrium of Adsorption of Oxyanions Cr (VI), Mo (VI) and Se (VI) by Quaternary Ammonium Chitosan SaltAbstract: Quaternary chitosan salt was synthesized in the presence of glycidyl trimetyl ammonium chloride. The polymer was characterized by spectroscopic techniques: infrared, 13 C and 1 H NMR, while the amount of quaternary ammonium groups was obtained by condutimetry. The removal of Cr (VI), Mo (VI) and Se (VI) from aqueous solutions was carried out in batch adsorption processes. The process seemed to be pH dependent for Cr (VI) and Se (VI) with an optimum pH ranging from 4.0 to 6.0; while for Mo (VI) the adsorption remained almost constant within the range between 4.0 and 11.5. The Langmuir isotherm model provided the best fit of the equilibrium data over the whole concentration investigated. In the experiment one gram of cross-linked quaternary chitosan salt adsorbed 68.3 mg of chromium, 63.4 mg of molybdenum and 90.0 mg of selenium. The adsorption process followed a pseudo second-order kinetic rate equation and the equilibrium regarding the three ions was reached after 200 minutes. The studies from X-ray dispersive energy showed that the main adsorption mechanism is ionic exchange among Cl -groups on the polymer surface by oxyanions from solution and the anionic exchanger showed the following selectivity order: Cr (VI) > Mo (VI) > Se (VI). Keywords: Adsorption, chromium (VI), molybdenum (VI), selenium (VI), quaternary chitosan salt.Autor para correspondência: Valfredo T. de Fávere, Departamento de Química, UFSC, Campus Universitário Trindade, CEP: 88040-900, Florianópolis, SC. E-mail: favere@qmc.ufsc.br IntroduçãoA preocupação e o interesse com as questões ambientais...

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“…When TMC was further quaternized to N,N,N-trimethyl O-(2-hydroxy-3-trimethylammonium propyl) chitosan (TMHTMAPC), it exhibited higher antibacterial activity than TMC [8]. N-[(2-hydroxy-3-trimethylammonium)propyl chitosan chloride (NHT-chitosan), which was easily prepared via coupling chitosan with glycidyl trimethyl ammonium chloride (GTMAC), had also been demonstrated to have a good moisture-retention capacity and antimicrobial activity against Staphylococcus aureus, E. coli and Candida albicans in alkaline conditions [9]. And O-acrylamide methyl-N-[(2-hydroxy-3-trimethylammonium)propyl] chitosan showed effective antibacterial activity against S. aureus and E. coli [10] either.…”

Section: Introductionmentioning

confidence: 99%