PAMAM dendrimer amine terminated

An interesting and novel potential use of dendrimers has been described by Menzel and co-workers who have developed photoluminescent dendrimers for fingerprint detection [101]. Amine terminated PAMAM dendrimer nanocomposites with cadmium sulfide were synthesised by the addition of methanolic solutions of cadmium nitrate and sodium sulfide to a methanolic solution of the dendrimer. Amine terminated dendrimers were selected so that they could form amide bonds with the carboxylic acids abundant in fingerprint residues. When bound to the fingerprint residues, the dendrimer composites serve as photoluminescent markers that aid detection. 

Crosslinking of amine- or hydroxy-terminated PAMAM dendrimers using cyclic anhydride - amine or cyclic anhydride - hydroxy addition reactions was employed for preparation of crosslinked thin films of very low permeability [73], Polyanhydrides, such as maleic anhydride-methyl vinyl ether copolymers, were used as crosslinking components. In the case of amine-terminated PAMAM, crosslinking and chemical stability were further increased by imidization of the maleamic acid groups retro-Michael eliminations were followed by Michael additions to further crosslink the film. 

In fact, it has been previously observed that measured diameters of dendrimer molecules by AFM are much larger than the theoretical values, which indicates that the dendrimers spread out and flatten on the surface [25, 26], Three major factors could account for this deformation. First, the unique architecture and chemical structure of PAMAM dendrimers result in macromolecules that are not solid balls, but instead are relatively open and hence soft materials. It is expected that the rigidity will increase substantially with increasing generation number [9]. Therefore, when deposited on solid substrates, they tend to deform to different degrees as a result of the interplay between their inherent rigidity and surface energetics from the interaction between the dendrimer molecules and the mica surface. Secondly, amine-terminated PAMAM dendrimers possess a... 

To a vigorously stirred solution of 1,2-diaminoethane (107 g, 118 ml, 1.781 mol) in methanol (150 ml), at 0°C under nitrogen, was added a solution of (G = 1.5) dentin -PAMAM(C02Me)16 [5] (10 g, 0.004 mol) in methanol (30 ml). The addition was controlled such that the temperature did not rise above 40 °C. The mixture was stirred at room temperature for 96 h, after which time no ester groups were detectable by NMR spectroscopy. The methanol was removed by vacuum distillation at < 40°C, and the excess 1,2-diaminoethane was removed by azeotropic distillation using a mixture of toluene and methanol (9 1). The remaining toluene was removed by azeotropic distillation with methanol and finally the methanol removed under vacuum (10 1 mm Hg, 50°C, 48 h) to give the amine terminated G = 2.0 dendrimer as a pale yellow oil (10.9 g, 94%). 

Various amine-terminated poly(amidoamine) (PAMAM) dendrimers were used as core reagents (i.e. G = 5, 6 and 7 -NH2 terminated), whereas various... 

Amine-terminated, G3 (PAMAM) dendrimer, (0.316 g 45.7 moles) was dissolved in anhydrous methyl sulfoxide (5 ml) in a 100 ml round-bottom flask flushed with dry nitrogen. After dendrimer had completely dissolved, succinic anhydride (Aldrich) (0.363 g 3.6 mmol) was added to the reaction mixture with vigorous stirring, and the mixture was allowed to react for 24 h at room temperature. The product solution was diluted with deionized water, transferred to 3500 MWCO dialysis tubing (Spectrum) and dialyzed against deionized water (18 Mil) for 3 d. The retentate solution was clarified by filtration through Whatman No. 1 filter paper, concentrated with a rotary evaporator, and lyophilized to yield a colorless powder (0.435 g, 94%). The product was analyzed by 13C-NMR, FT-IR, SEC and MALDI-MS. The analytical data were consistent with the expected carboxylic acid-terminated product. 

---