PAMAM dendrimers groups

PAMAM) dendrimers groups at the dendrimer surface transfections Kukowska-Latallo etal., 1996)... 

Fig. 2. Poly(amidoamine) (PAMAM) dendrimers with carboxylate groups at the external surface...

Activated PAMAM dendrimers interact with DNA to form a DNA-dendrimer complex with a toroid-like structure (Fig. 2). Such DNA-dendrimer complexes have diameters of 50-100 nm [10],which means that the DNA molecules are highly condensed in these complexes. A 6-kb plasmid alone, for example, has an extended structure several hundred nanometers in diameter. In transfection experiments, typically an 8- to 12-fold excess of positive amino groups over negatively... 

Recently, the Okada group described a new class of polymerization systems [43] oligoglycopeptide-type sugar-balls were obtained by a radial growth polymerization (RGP) of a-amino acid AT-carboxyanhydrides with PAMAM dendrimers of different generations. 

Fig. 9. 3rd-Generation PAMAM-dendrimer functionalized with disaccharide end groups [42]... 

Figure 7.1 The synthesis of a PAMAM-type dendrimer proceeds from a diamine core [e.g., ethylene diamine (EDA)] by initial addition of the amines to the double bonds of methacrylate. Subsequent reaction of the methyl ester groups with EDA produces a G-0 dendrimer with four pendent amine groups. Another round of methacrylate and EDA additions results in a G-l PAMAM dendrimer containing eight primary amines.

Other than the epoxy groups available on one Priostar dendrimer type and a methyl ester available on a PAMAM dendrimer, the commercial suppliers generally don t offer a selection of spontaneously reactive dendrimers for bioconjugation purposes. For this reason, most of the applications published for coupling biomolecules to dendrimers have used various modification or activation steps to create the appropriate reactive groups for conjugation (e.g., Leon etal., 1996). 

Acylation reactions to block amine groups on PAMAM dendrimers with anhydride compounds are done in a similar manner to glycidol modification. The following protocol is based on the method of Majoros et al., 2005. 

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