Poly -based dendritic

Scheme 4.14. Lysine-based, dendritic terminated poly(ethylene oxide) was described as hydroamphiphiles due to the formation of stable foams in water.

Metal-acetylide complexes including metal-poly(yne) polymers often show unique properties [21-23]. Thus, metal-acetylide dendrimers are of interest because amplification of the functionality due to metal-acetylide units based on three-dimensional assembly with a regular dendritic structure is expected. 

Other supramolecular structures such as dendrimers have also been synthesized with zinc-containing porphyrins. Sixteen free base and sixteen zinc porphyrin units were added at the fifth generation of dendritic poly(L-lysine) and intramolecular fluorescence energy transfer was observed.823 Assembly of supramolecular arrays in the solid state has been achieved with the incorporation of an amide group for hydrogen bonding. Zinc meso-tetra(4-amidophenyl)porphyrin... 

Akagi T, Wang X, Uto T et al (2007) Protein direct delivery to dendritic cells using nanoparticles based on amphiphilic poly(amino acid) derivatives. Biomaterials 28 3427-3436... 

Elamanchili P, Diwan M, Cao M et al (2004) Characterization of poly(D, L-lactic-co-glycolic acid) based nanoparticulate system for enhanced delivery of antigens to dendritic cells. Vaccine 22 2406—2412... 

Other efforts based on the macromonomer approach to homopolymers having dendritic side chains, include the work of Draheim and Ritter on acrylate and methacrylate derived structures having dendritic chiral side chains based on L-aspartic esters [17a], and of Xi and coworkers with poly(methacrylate) structures containing very small benzyl ether dendritic side-chains [17b]. Unfortunately, both of these approaches met with limited success due to a significant drop in degree of polymerization (DP) when the size of the dendron used as pendant group in the macromonomers increased from G-l to G-2. 

Miller and co-workers have recently prepared nanometer-scaled molecular dumbbells based on poly(benzyl ether) dendrons (G1-G4) and oligoimide spacers [64], Their synthetic approach involved the coupling of amine-terminated oligoimides to dendrons with a carboxylic acid focal point. The resulting hybrid materials were found to be quite soluble thus allowing their analysis by cyclic voltammetry in DMF. Consistent with Roncali s observation, the kinetics of reduction of the oligoimide core was not found to be limited by the presence of the dendritic wedges. 

Analysis by XPS after incorporation of the linear or dendritic cationic polymers showed an increase in the atom % N consistent with incorporation of an N-rich polycation. The polyvalent interactions between the cationic polyelectrolytes and the poly(sodium acrylate)graftson PE were stable to Soxhlet extraction with 95% ethanol, repeated acid/base treatment, and soaking or sonication in isopropanol and THE However, in these cases, simple acid treatment did not release the cationic polymer as was the case with PAA/Au grafts even though grafting in both cases was reportedly ionic and not covalent. 

In addition, taper-shaped and dendritic units were connected either covalently (at the apex or at the periphery) [133,135, 383,405] or by means of self assembly (e.g., hydrogen bonding [399]) to a polymer backbone. For example, polymers based on poly[4-(3-methacryloylpropyl]pyridine] form hydrogen bonded complexes with partially fluorinated mono-, di-, or trisubstituted benzoic acids (see complex 221 in Fig. 72). The type of mesophase formed by these complexes varies from smectic via columnar to cubic, most probably micellar cubic, with rising... 

Poly(amido amine) (PAMAM) dendrimers are the most common class of dendritic macromolecules and, due to their ease of synthesis and commercial availability, they have been the most utilized dendrimer-based vectors for gene transfer [1, 37, 84]. PAMAM dendrimers consist of an alkyl-diamine core with tertiary amine... 

Kaneda et al. [33,34] have recently utilized acid-base interactions to non-covalently attach diphenylphosphine-4-benzoic acid palladium complexes to the exterior of poly(propyleneimine) dendrimers and to cavities within these dendrimers (Fig. 9) via the interaction of the benzoic acid with the carboxyl groups of amide moieties positioned within the dendrimer. Interestingly, the supramolecular dendritic catalyst gave rise to much more active catalysts for... 

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