Absorption enhancers chitosan

Hamman et al. [281,282] tested five trimethyl chitosans with different degrees of quaternization as nasal delivery systems the degree of quaternization had a major role in the absorption enhancement of this polymer across the nasal epithelia in a neutral environment. 

Tengamnuay P, Sahamethapat A, Sailasuta A, Mitra AK (2000) Chitosans as nasal absorption enhancers of peptides comparison between free amine chitosans and soluble salts. Int J Pharm 197 53-67. 

Thanou M, Verhoef JC, and Junginger HE (2001) Chitosan and its derivatives as intestinal absorption enhancers. Adv. Drug Deliv.Rev. 50 S91-S101. 

Cano-Cebrian MJ, Zornoza T, Granero L, and Polache A (2005) Intestinal absorption enhancement via the paracellular route by fatty acids, chitosans and others A target for drug delivery. Curr. Drug Deliv. 2 9-22. 

Thanou M, Verhoef JC, Junginger HE (2001) Oral drug absorption enhancement by chitosan and its derivatives. Adv Drug Del Rev 52 117-126... 

Ilium et al. [49] evaluated chitosan solutions as delivery platforms for nasal administration of insulin to rats and sheep. They reported a concentration-dependent absorption-enhancing effect with minimal histological changes of the nasal mucosa in all concentrations applied. 

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. 

Drug release and retention at the site of absorption are very important for the enhancement of the bioavailability, particularly when the absorption sites are localized to a certain area of the GI route. This control of the transition of the drug can be achieved using bioadhesive excipients. Chlorothiazide (CT), a diuretic and antihypertensive drug, was better orally absorbed when administered with mucoadhesive polymers [25], The absorption of CT is considered to be saturable and site-specific, because a low dose is better absorbed, and a decreased stomach emptying rate and slow GI transition rate are better for increased absorption. As chitosan is a mucoadhesive polymer, the absorption of CT is expected to be enhanced... 

Chitosan not only displays mucoadhesive properties, but also acts as an absorption enhancer in the intestinal cell layer membrane [34,35]. The mucoadhesion raises the concentration of... 

Therefore, the enhancement of transport is not accompanied by damage to the cells, which is superior to the absorption-enhancing effects of other small molecules, which lead to irreversible changes in the cell membrane and damage to the cell. Thus, much attention has been paid to chitosan as a polymeric substance that enhances GI absorption. 

Schipper, N.G.M., et al. 1999. Chitosans as absorption enhancers of poorly absorbable drugs 3 Influence of mucus on absorption enhancement. Eur J Pharm Sci 8 335. 

Aspden, T.J., L. Ilium, and O. Skaugrud. 1996. Chitosan as a nasal delivery system Evaluation of insulin absorption enhancement and effect on nasal membrane integrity using rat models. Eur J Pharm Sci 4 23. 

Schipper, N. G., Olsson, S., Hoogstraate, J. A., et al. Chitosans as absorption enhancers for poorly absorbable drugs 2. Mechanism of absorption enhancement. Pharm. Res. 14 923-929, 1997. 

A-Trimethyl Chitosan as Absorption Enhancer of Peptide Drugs. Ill... 

Thanou, M., Verhoef, J.C. Romeijn, S.G., Nagelkerke, J.F., Merkus, F.W.H.M. and Junginger, H.E. (1999) Effects of A-trimethyl chitosan chloride, a novel absorption enhancer, on Caco-2 intestinal epithelia and the ciliary beat frequency of chicken embryo trachea. Int. J. Pharm. 185 73-82. 

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