Chitosan molecular weight

Chitosan molecular weight has also been reported to influence drug release. Jiang et al. [94] studied Bordetella bronchiseptica dermonecrotoxin (BBD) release from chitosan microspheres prepared by tripolyphosphate ionic gelation. It has been shown that the BBD release rate increased with chitosan molecular weight decrease. It has been explained by the weaker BBD interaction with chitosan of lower molecular weight and lower content of free amine groups, responsible for their interaction. 

Microspheres Ionic gelation process with tripolyphosphate Bordetella, bronchiseptica, dermonecrotoxin Chitosan In vitro Chitosan molecular weight-related drug release profile 94... 

Yang J, Tian F et al (2008) Effect of chitosan molecular weight and deacetylation degree on hemostasis. J Biomed Mater Res B Appl Biomater 84B 131-137... 

Prego, C., Torres, D., Alonso, M. J. Chitosan nanocapsules as carriers for oral peptide delivery Effect of chitosan molecular weight and type of salt on the in vitro behavior and in vivo effectiveness. Nanosci. NanotechnoL, 6, 2921, 2006. 

Wu T, Zivanovic S, Hayes DG, Weiss J (2008) Efficient reduction of chitosan molecular weight by high-intensity ultrasound underlying mechanism and effect of process parameters. J Agric Food Chem 56 5112-5119... 

Broad spectrum antimicrobial against G+ve and G-ve bacteria and fungi-tested -The extent of improvement in the imparted properties (antimicrobial/durable press] was determined by t q)e and concentration of cross-linker, chitosan molecular weight and cone. As well as finishing condition. 

PEGylated chitosan nanoparticles were shown to enhance insulin absorption to a greater extent compared with non-nanoparticulate forms of chitosan and insulin alone. Chitosan nanoparticles were also found to enhance nasal absorption of insulin in rabbit, regardless of chitosan molecular weight. Recently, Al-Qadi and co-workers reported that intratracheal administration of diy insulin powder microencapsulated in chitosan nanoparticles increased its distribution to the deep lungs, and facilitated release of a biologically active form of insulin to rat blood. Moreover, they observed a more pronounced and prolonged effect compared to non-formulated insulin. ... 

DNA molecules (polyplexes). Although there are a lot of reports on chitosan-based DNA nanocarriers varying in sizes (20-250 nm and higher), studies regarding effects and the chitosan-specific transfection mechanisms remain insufficient. It is shown that the level of transfection depends upon several factors, for instance chitosan molecular weight (from 22 kDa [65] to 400 kDa [66]), the ratio of chitosan nitrogen to DNA phosphate (N/P ratio), as well as serum concentration and pH of transfection medium, and finally on cell line [67],... 

Bercheran-Maron L., Peniche C., AtgueUes-Monal W., Study of the interpolyelectrolyte reaction between chitosan and alginate Influence of alginate composition and chitosan molecular weight, Int. J. Biol. Macromol, 34, 2004,127-133. 

On the contrary, chitosan holding in an acetic acid solution in the presence of the enzymes leads to considerate reduction in the sedimentation constant and increase of the diffusion coefficient (see Table 8.1). Thus, it results in significant reduction of the chitosan molecular weight taking place during the biodegradation process. 

Chitosan (molecular weight, 19-400 kDa degree of deacetylation, 75-98%) has been evaluated as a directly compressible vehicle for tablets, but has found limited utility due to the lack of good flow properties and compressibility. The influence of excipient (lactose, sodium lauryl sulfate, sodium alginate, hydroxypropyl methyl... 

The molecular weight and its distribution are also important. Commercial chitosan samples may have molecular weights up to 4 x 10 Da. The Mark Houwink equation [ ] = kM, is used to obtain a viscosity average molecular weight. However, the values of k and a are most likely functions of the degree of deacetylation (21). Gel permeation chromatography is also suited for the determination of chitosan molecular weight and polydispersity (21). 

F Abd-Elmohdy, Z. El Sayed, S. Essam, and A. Hebeish, Controlling chitosan molecular weight via bio-chitosanolysis. Carbohydrate Polymers, 82 (3), 539-542, 2010. 

Moran, M.C., Laranjeira, T., Ribeiro, A., Miguel, M.G., Lindman, B. Chitosan-DNA particles for DNA delivery effect of chitosan molecular weight on formation and release characteristics. J. Dispersion Sci. Technol. 30(10), 1494-1499 (2009)... 

As the chitosan molecular weight in the chitosan-DNA complex increased, the Texas Red-labeled chitosan gradually lost FRET-induced fluorescence when HEK293 cells incubated with chitosan-DNA complex were examined under the confocal microscope. This was indicative of the fact that the dissociation of the chitosan-DNA complex was more extended for HMW chitosan-DNA complexes. Fluorescence spectroscopy also monitored the molecular dissociation of the chitosan-DNA complex at pH 7.4 and pH 5.0 and confirmed that the dissociation occurred in acidic environments. This finding suggests that the high molecular weight chitosan-DNA complex could easily be dissociated in lysosomes compared... 

---