Chitosan dodecylated

Thongngam, M., McClements, D.J. (2005). Influence of pH, ionic strength, and temperature on self-association and interactions of sodium dodecyl sulfate in the absence and presence of chitosan. Langmuir, 21, 79-86. 

Fetih, G., et al. 2005. Improvement of absorption enhancing effects of /j-dodecyl-beta-D-maltopyr-anoside by its colon-specific delivery using chitosan capsules. Int J Pharm 293 127. 

Li et al. [37] described a series of A iV-dialkyl chitosans (alkyl = octyl, decyl, and dodecyl) (Fig. 7d), which in neutral water formed stable bilayered vesicles having hydrodynamic diameters in the range of 100-200 nm (DLS). It was found that the size of vesicles increased with increasing molecular weight of the hydrophilic chitosan backbone and/or increasing length of the hydrophobic alkyl side chains, which was attributed to a more compact structure of the membrane. 

In more recent studies (51, 52) the biopolymer chitosan was used as an emulsifier in food double emulsions. Chitosan has surface activity and seems to stabilize W/OAV emulsions. Chitosan reacts with anionic emulsifiers such as sodium dodecyl sulfate at certain ratios to form a water-insoluble complex that has strong emulsification capabilities. Chitosan solution was used to form double emulsions of OAV/0 as intermediates fi om which by a simple procedure of stripping the water the authors formed interesting porous spherical particles of chitosan (52). 

Ammonium nonoxynol-4 sulfate Ammonium nonoxynol-6 sulfate Ammonium phosphate Antimony trichloride Butylated PVP Ceteareth-4 Ceteareth-6 Ceteareth-8 Ceteareth-10 Ceteareth-11 Ceteareth-14 Ceteareth-18 Ceteareth-80 Chitosan Chloro-2-hydroxypropyl trimonium chloride Cyanamide-formaldehyde resin Dibehenyidimonium chloride Diethylene glycol Disodium arsenate Hydrogenated tallowalkonium chloride Hydroxylamine sulfate lsodeceth-6 Lauryl hydroxyethyl imidazoline Lysolecithin MEA-dodecylbenzene sulfonate Octoxynol-25 Oleth-18 Oxalic acid dihydrate PCA PEG-80 castor oil PEG lauramine PEG laurate PEG-20 laurate PEG-14 oleate PEG-5 stearate PEG-23 stearate PEG-8 tallate Potassium acid tartrate Sodium arsenate Sodium chromate Sodium dodecyl diphenyloxide disulfonate Sodium methyl oleoyl taurate Sodium methyl tallow taurate Sodium sulfate... 

The ion separation concern several ions such as Co(II), Ni(II), Zn(ll), Cr(III), and Cd(ll). Depending on the membrane characteristics, it can achieve more than 90 % of removal efficiency with metal concentration from 10 to 112 mg/L. In principle, the separation could be enhanced by using a surfactant such as sodium dodecyl sulfate (SDS) to form micelles or a water-borne polymer such as chitosan to complex ions. However, the membrane fouling problems have hindered this technique from a wider industrial waste-water treatment. 

Journal of Applied Polymer Science 82, No. 14,27th Dec.2001, p.3391-5 FORMATION OF A DNA/N-DODECYLATED CHITOSAN COMPLEX AND SALT-INDUCED GENE DELIVERY... 

A polyelectrolyte complex was formed by synthesising an N-dodecylated chitosan, from dodecyl bromide and chitosan, and assembling with DNA. Atomic force microscopy was used to examine the thermal stability of the DNA embedded in the polyelectrolyte complex. From this it was seen that the incorporation of the dodecylated chitosan enhanced the thermal stability of DNA, due to encapsulation of DNA in the chitosan. The dissociation of the complex induced by small molecular salts was investigated. The ability of Mg2+ to break the polyelectrolyte complex is greater than that of Na+ and K+. From the atomic force microscopy images it can be seen that the DNA is well protected by the dodecylated chitosan from nuclease. The polyelectrolyte complex can be used as a gene delivery carrier. 21 refs. 

Forces between BSM layers preadsorbed on negatively charged mica surfaces have also been reported by Dedi-naite et al. [33]. They also found long-range steric interactions to be predominant, but they did not explore the effect of ionic strength. However, they showed that the anionic surfactant sodium dodecyl sulfate, SDS, has the ability to remove mucin from the surface and that adsorption of chitosan, a cationic polysaccharide, on top of mucin can protect the mucin layer from being removed by the surfactant. 

The first example of a calixarene-based SEN, layer-by-layer coated with DNA cargo, was recently published by the Shahgaldian group The authors prepared the SLNs by the nanoprecipitation method, starting from the well known tetraaminocalix[4]arene with dodecyl tails at the lower rim. Plasmid DNA was coated on the SEN surface, followed by alternating coatings with plasmid DNA and polycationic labeled chitosan. MDCK cells were transfected with the new DNA carrying materials, and no decrease in cell viability was observed. Uptake into the cell was confimed by confocal microscopy and GFP expression [77]. 

The receptor ligand transferrin has been incorporated into chitosan/DNA polyplexes which enhanced gene transfer up to four-fold compared to immod-ified chitosan [67]. In a similar fashion, incorporation of C-terminal domain of adenovirus fiber knob protein enhanced transfection up to 130-fold in HeLa cells. Further modifications include the incorporation of hydrophobic moieties to generate dodecylated chitosan, deoxychoHc acid modified chitosan. Urocanic acid-modified chitosan [68] was reported to mediate efficient gene delivery it was hypothesized that the imidazole ring plays a crucial role for enhancing the release of internalized polyplexes from endosomal vesicles. 

As described above, interactions between oppositely charged surfactants and polyelectrolytes in aqueous solutions can lead to associative phase separation, where the concentrated phase assumes the form of a viscous liquid, gel, liquid crystal or precipitate. This behavior has been exploited to form gel particles, which have been prepared by drop-wise addition of cellulose-based polycation solution (chitosan or-, N,N,N-trimethylammonium derivatized hydroxyethyl-cellulose) to anionic (sodium dodecyl sulfate, sodium perfluorooctanoate) and cationic (cetyltrimethylammonium bromide/sodium perfluorooctanoate) surfactant solutions [76-80]. 

Kriegel et al. [165] again found that the addition of PEO (25% of polymer content) facilitated fiber formation from chitosan. They included in the blend fibers different surfactants, i.e. sodium dodecyl sulfate (SDS), dodecyltrimethylammonium bromide (DTAB) and polyoxyethylene glycol (23) lauryl ether (Brij 35). The surfactants can be retained in the nanofibers either in the form of micelles or monomers. Furthermore, the addition of... 

The materials used in this study include (a) natural flake graphite and sodium dodecyl sulfate (SDS) from Sigma Aldrich, (b) the aniline monomer was obtained from Aldrich and purified by vacuum distillation and kept under nitrogen in a refrigerator at about 4°C prior to use, (c) medium molecular weight chitosan powder with = 480 KDa and DD = 75-85%... 

Ngimhuang, J., Furukawa, J., Satoh, T., Furuike, X, Sakairi, N. Synthesis of a novel polymeric surfactant by reductive N-alkylation of chitosan with 3-O-dodecyl-glu-... 

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