Tripolyphosphate gelation

Femandez-Urrusuno et al. (1999) investigated the potential of chitosan (MW <50,000-130,000 DD 70-87%) nanoparticles as a system for improving the systemic absorption of insulin following nasal instillation. Nanoparticles prepared by ionotropic gelation with tripolyphosphate... 

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 with tripolyphosphate Bordetella, bronchiseptica, dermonecrotoxin Chitosan In mice Systemic and mucosal immune responses induced 21... 

Tsai, M.-L., Bai, S.-W., and Chen, R.-H. (2008). Cavitation effects versus stretch effects resulted in different size and polydispersity of ionotropic gelation chitosan-sodium tripolyphosphate nanoparticle. Carbohydr. Polym. 71, 448-457. 

A-(2-Hydroxyl) propyl-3-trimethyl ammonium chitosan chloride (HTCC) is a water-soluble derivative of chitosan (CS), synthesized by the reaction between glycidyl-trimethyl-ammonium chloride and CS. HTCC nanoparticles have been formed based on ionic gelation process of HTCC and sodium tripolyphosphate (TPP). Bovine serum albumin (BSA), as a model protein drug, was incorporated into the HTCC nanoparticles. HTCC nanoparticles were 110-180nm in size, and their encapsulation efficiency was up to 90%. In vitro release studies showed a burst effect, followed by a slow and continuous release. Encapsulation efficiency was obviously increased with increase in initial BSA concentration [15]. 

The ionic gelation method has received tremendous attention in recent years for the preparation of nanocarriers for low molecular dmgs [148]. As far as chitosan-based nanoparticles are concerned, sodium tripolyphosphate (TPP) is usually used as ionic crosslinking agent. Chitosan-based nanoparticles can also be prepared using self-assembly methods. In this case, polyanionic compounds are selected and then allowed to react separately with chitosan and modified chitosan. Electrostatic... 

Chitosan is a promising polymer for colon delivery because it can be biodegraded by the colonic microflora and it has mucoadhesive character. A thorough study has been carried out on chitosan beads obtained by ionotropic gelation with alginate or tripolyphosphate. The aim was to develop, using natural polymers, a controlled release system that would resist the conditions in the stomach and release its drug... 

Chitosan as the cationic polysaccharide has been used with the anionic polysaccharides, carrageenan, and alginate for ionic complexation. Chitosan-carrageenan nanoparticles cross-linked with tripolyphosphate were prepared by corporation of polyelectrolyte complexation and ionic gelation (Grenha et al., 2010). 

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