Cyclodextrin-modified polymers

The behaviors and properties of polymers may also be modified with CDs and additive-CD-ICs. Because CD-ICs formed with smaU-molecule additives, such as antibacterials and flame retardants, are stable to temperatures beyond 250 °C, they may be compounded intact into many molten polymers. In this manner antibacterial and flame-retardant polymer fibers and films have been achieved. 

5 Schematic representation of an HASE associative polymer and the molecular constitution of the HASE polymer used in this study. R refers to the C22H45 hydrophobe, p = 40, and xjylz = 43.6/56.2/0.20 by mole. 

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Fig. 3 Photoresponsive polymer surface sensitive to pH and light. Adsorption and release of cytochrome c triggered by pH (b, c, and d) release of the polymer layer and cytochrome c by breaking the host-guest interactions between surface-tethered azo dye and cyclodextrin via light irradiation (a and d). The molecular structure on the right represents the host-guest complexa-tion of the azo dye with the cyclodextrin-modified poly(acrylic acid). Reprinted, with permission, from [68]. Copyright (2009) Wiley Interscience...

Solid lipid poly(lactic acid) (PLA), poly(lactide-co-glycotide) (PLGA), poly(e-caprolactone) (PCL), poly(methyl methacrylate), and poly(alkyl cyanoacrylate) derivatives of cyclodextrin and starch some modified polymers (e.g., PEGylated polymers) also used Mainly glycerides and High-pressure... 

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. 

Pun S H, et al. (2004). Cyclodextrin-modified polyethylenimine polymers for gene delivery. Bioconjug. Chem. 15 831-840. 

Suzuki I, Sato K, Koga M, Chen Q, Anzai J I. 2003. Polyelectrolyte layered assemblies containing azobenzene modified polymer and anionic cyclodextrins. Mater Sci Eng C 23(5) 579 583. 

Besides charged species, the inclusion of hydroxypropyl-(3-cyclodextrin during polymer electrogeneration has been reported in a number of papers dealing with analytical applications, particularly involving PEDOT [56, 65-70], Although the actual role of this species has not been well defined, the performance of similarly modified electrodes is found to be positively affected by its presence inside the film. 

Wang X, Chen C, Huo D, Qian H, Ding Y, Hu Y, Jiang X. Synthesis of P-cyclodextrin modified chitosan-poly(acrylic acid) nanoparticles and use as drug carriers. Carbohydr Polym. 

Karlson, L., Thuresson, K. and Lindman, B. (2002) A rheological investigation of the complex formation between hydrophobicaUy modified ethyl (hydroxy ethyl) cellulose and cyclodextrin. Carbohydr. Polym., 50 (3), 219-226. 

Karakasyan, C., Millot, M.-C., and Vidal-Madjar, C. Immobilization of a (dextran-adamantane-COOH) polymer onto [beta]-cyclodextrin-modified silica. J Chromatography B 2004, 808 63-67. 

A. Kitajima, T. Teranishi, and M. Miyake, Detection of nitric oxide on carbon electrode modified with ionic polymers and alpha-cyclodextrin. Electrochemistry 69, 16-20 (2001). 

Over 100 stationary phases of various types have been described in the literature for packed columns, which are slowly being abandoned. However, for bonded phase capillary columns the choice of stationary phase is limited because the generation of the film at the surface of the column requires a different principle than impregnation. Generally, two families of compounds are used to modify the polarity polysiloxanes and polyethylene (silicones) glycols. Very special phases such as cyclodextrins can be used for enantiomeric separations. Stationary phases can be used between a minimum temperature under which equilibrium is too slow to occur and a maximum temperature above which degradation of the polymer occurs. The maximum temperature depends on the film thickness and the nature of the polymer. 

Inclusion properties of molecular nanotubes composed of crosslinked a-cyclodextrin was investigated [47], Induced circular dichroism was used to probe the formation and dissociation of complexes between the nanotubes and azobenzene modified polyethylene glycol), either with or without a hydrophobic alkyl chain. The inclusion complex between the nanotubes and polymers formed at room temperature, and the polymers dissociated from the nanotubes with increasing temperature. 

The complex multicomponent system, called CALAA-01, has been developed by Davis for Calando Pharmaceuticals and is the first of many possible RONDEL therapeutics based on a biomimetic approach to drug delivery [24], The approach combines a linear cationic polymer that incorporates cyclodextrins, a therapeutic payload (siRNA strands that target a specific process), and adamantane molecules modified with biocompatible polyethylene glycol chains (PEGs) or complementary proteins that bind to the target cell types. 

The utility of the highly soluble 6-cyclodextrin derivatives (soluble polymer and dimethyl-6-cyclodextrin) in RPTLC is illustrated in the separation of barbiturates. The lipophilicity of a barbiturate or any guest decreases when included in a cyclodextrin-cavity. Therefore its mobility is modified in reversed phase thin layer chromatography. With this simple and rapid method, the stability of a complex can be estimated empirically (Table II). The "b" value of the following equation is characteristic for the complex stability (in water ethanol =4 1 solution, R determined at 5 different cyclodextrin concentrations for 21 barbiturates) ... 

Amphiphilic Cyclodextrins Nanoparticles have been obtained spontaneously from modified CDs of amphiphilic structure since the last decade. This approach differs from the previously discussed approaches in that amphiphilic CDs do not require the presence of another polymer or macromolecule or even surfactants. 

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