Drug delivery cyclodextrins used

Some of the compounds previously discussed have been used in formulation studies with the eventual aim of enhancing the bioavailability and activity in vivo. The ferrocenyl compounds discussed here are quite hydrophobic, necessitating a drug delivery system. Compounds 4, 5, 7 and 36 were found to create 1 1 water soluble inclusion complexes with methylated (3 cyclodextrin (CD) after stirring overnight. Electrochemical experiments showed that, in methanol, they exhibited a weak interaction with the CD cavity, and that these interactions became stronger as the amount of added water increased, as expected. 

Wang [3] prepared the amphiphilic biocompatible cyclodextrin graft polymer, poly(ethylene glycol-g-cyclodextrin), (III), containing modified cyclodextrin which was used as a bioactive drug delivery agent. 

Wang [1] prepared biocompatible cyclodextrin grafted polymers, (I), consisting of hydrophobically modified cyclodextrin with a biocompatible hydrophilic polymer backbone that were used as drug delivery agents. 

In addition to traditional dermal and transdermal delivery formulations, such as creams, ointments, gels, and patches, several other systems have been evaluated. In the pharmaceutical semisolid and liquid formulation area,these include sprays, foams, multiple emulsions, microemulsions, liposomal formulations, transfersomes, niosomes, ethosomes, cyclodextrins, glycospheres, dermal membrane structures, and microsponges. Many of these novel systems use vesicles to modulate drug delivery. Novel transdermal... 

Yui s group has investigated biodegradable polymers based on the cyclodextrin-based polyrotaxanes over the course of the last decade [128-139]. First, they prepared polyrotaxanes from a-cyclodextrin and PEG bisamine (Scheme 23) [128]. For example, l-phenylalanine was employed as an enzymatically hydrolyzable endcap. The in vitro degradation experiments using papain showed that a-cyclo dextrin was indeed released only when the terminal peptide linkages were hydrolyzed. They have prepared various kinds of polyrotaxanes based on cyclodextrin and have demonstrated that these polyrotaxanes are effective as drug delivery systems. 

Alternative means that help overcome these nasal barriers are currently in development. Absorption enhancers such as phospholipids and surfactants are constantly used, but care must be taken in relation to their concentration. Drug delivery systems, including liposomes, cyclodextrins, and micro- and nanoparticles are being investigated to increase the bioavailability of drugs delivered intranasally [2]. 

Qi, Z.H. and Sikorski, C.T. (2001) Controlled drug delivery using cyclodextrin technology, Pharm. Technol. Eur., 13, 17-27. 

Cyclodextrin-linked CS Reductive amination using formylmethylene, crosslinking by glutaraldehyde and so on Form non-covalent inclusion complexes with a number of molecules altering their physicochemical properties Drug delivery... 

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