Synthesis, characterization and in vitro biological properties of O-methyl free N,N,N-trimethylated chitosan

Verheul, Rolf J.; Amidi, Maryam; Wal, Steffen van der; Riet, Elly van; Jiskoot, Wim; Hennink, Wim E.

doi:10.1016/j.biomaterials.2008.05.026

Cited by 195 publications

(138 citation statements)

References 28 publications

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“…Generally, during chitosan trimethylation synthesis, O-methylation at C-6 and C-3 may occur, leading to uncontrolled trimethylation. Moreover, O-methylation leads to chain scission resulting in reduced polymer solubility (Verheul et al, 2008). In this case, treating chitosan first with formic acid and formaldehyde and secondly with methyl iodide, would help to overcome this issue of uncontrolled trimethylation (Patrulea et al, 2015).…”

Section: Tmcmentioning

confidence: 99%

Chitosan as a starting material for wound healing applications

Patrulea

Ostafe

Borchard

et al. 2015

European Journal of Pharmaceutics and Biopharmaceutics

487

215

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Abstract:Chitosan and its derivatives have attracted great attention due to their properties beneficial for application to wound healing. The main focus of the present review is to summarize studies involving chitosan and its derivatives, especially N,N,N-trimethylchitosan (TMC), N,O-carboxymethyl-chitosan (CMC) and O-carboxymethyl-N,N,Ntrimethyl-chitosan (CMTMC), used to accelerate wound healing. Moreover, formulation strategies for chitosan and its derivatives, as well as their in vitro, in vivo and clinical applications in wound healing are described.

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Section: Tmcmentioning

confidence: 99%

Chitosan as a starting material for wound healing applications

Patrulea

Ostafe

Borchard

et al. 2015

European Journal of Pharmaceutics and Biopharmaceutics

487

215

View full text Add to dashboard Cite

show abstract

“…In this study, N,N,N-trimethyl-N-dodecyl chitosan was synthesized with chitosan as the raw material, in consideration that the introduction of N-trimethyl might increase its water-solubility and permeability in neutral pH environment (Chen et al, 2008;Verheul et al, 2008;Yin et al, 2009), and the introduction of dodecyl might improve its emulsifying capacity. Besides, N,N,N-trimethyl-N-dodecyl chitosan might potentiate the steric hindrance effect of chitosan thus effectively protect Tat against degradation in GIT.…”

Section: Discussionmentioning

confidence: 99%

Modified nanoparticles with cell-penetrating peptide and amphipathic chitosan derivative for enhanced oral colon absorption of insulin: preparation and evaluation

et al. 2015

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(2016) Modified nanoparticles with cell-penetrating peptide and amphipathic chitosan derivative for enhanced oral colon absorption of insulin: preparation and evaluation, Drug Delivery, 23:6, 2003-2014, DOI: 10.3109/10717544.2015 AbstractColon is an ideal absorptive site for oral protein and peptide drug (insulin), and yet it poses multiple barriers against the drug absorption, such as the barriers against the drug diffusion from colon lumen toward the absorptive mucosa and permeation across colon epithelium. In this study, modified nanoparticles (Tat-CS-NPs) with cell-penetrating peptide (Tat) and amphipathic chitosan derivative (a-CS) were used as carriers to improve colonic absorption of the drug. With a-CS as emulsifier and poly(lactic-co-glycolic acid) as matrix material, Tat-CS-NPs were prepared and evaluated in vitro/vivo. Using Caco-2 cell monolayers to imitate the colonic epithelial cells, it was found that the cellular uptake amount and transcellular transportation performance of Tat-CS-NPs were much enhanced compared with those of CS-NPs and PVA-NPs. The efficacy evaluation on diabetic rat models demonstrated that the hypoglycemic effect of Tat-CS-NPs loaded with insulin was 6.89 times higher than that of PVANPs, and 1.79 times higher than that of CS-NPs. By gavage of [ 99m Tc] isotope labeled Tat-CS-NPs in mini-pigs and single-photon emission computed tomography (SPECT) on pigs' gastrointestinal tract, it was further proved that the nanoparticles could reach colon and produce pharmacological effect. In conclusion, Tat-CS-NPs as vehicles for colon-specific drug delivery may be an efficient approach to improve oral bioavailability of protein and peptide drugs.

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“…Results obtained where Caco-2 cell monolayers were tested with the propidium iodide nucleic stain for their viability after 4 h of exposure to TMC (40 and 60% quaternized) in concentrations up to 1% w/v, showed that the monolayers excluded the nucleic stain, demonstrating that TMC does not effect the cell viability (Thanou et al, 2001). Various studies have confirmed that TMC is a safe mucoadhesive polymer and absorption enhancer for hydrophilic macromolecules across various mucosal sites (Amidi et al, 2006;Verheul et al, 2008). According to previous studies the cytotoxicity of TMC increases with higher degrees of quaternization and molecular weight (Yin et al, 2009;Amidi et al, 2010).…”

Section: Discussionmentioning

confidence: 99%