Ethylenediamine core

Add 50 pi of the NHS-PEGg-maleimide solution to the 1ml dendrimer solution and mix thoroughly to dissolve. This represents approximately a 14-fold molar excess of crosslinker over the quantity of dendrimer present, if a G-3 PAMAM dendrimer is used with an ethylenediamine core. The optimum molar ratio of crosslinker-to-dendrimer should be determined experimentally for best performance of the resultant conjugate in its intended application. If enough material is available, doing a series of experiments at different mole ratios of crosslinker-to-dendrimer will help to optimize the resultant conjugate. 

Scheme 9. (A) Different dendrimers as macromolecular scaffolds for MRI contrast agents ethylenediamine cored polyamido amine, generation 4 (PAMAM G4), top hyperbranched, ethylenediamine cored polyethylene imine (HB-PEI), bottom left hyperbranched, amino functionalized polyglycerol (HB-PG), bottom right. (B) Different moieties attached to the respective dendrimers via amide or thiourea bonds.

PAMAM dendrimers, and in the binding of probes to PAMAM dendrimers with an ethylenediamine core [23]. 

Comparative evaluation of anti-human thyroid stimulating hormone (hTSH) antibody, bound to the fifth-generation ammonia core (N5) or the fifth-generation ethylenediamine core (E5) dendrimer (1), did not show any differences in either the effective protein concentrations or the shape of the dose-dependent response curves (calibration curves) as determined from the recovery of standard controls. All the other experiments described here were thus carried out with the fifth-generation (i.e. dia. = 70 A) particles of ethylenediamine core (E5) de-ndrimers. The later particles were selected for their ability to be produced reproducibly on a large scale. 

Fig. 4.7 Synthesis of PAMAM dendrimers — with tetrafunc-tional ethylenediamine core (according to Tomalia et al.)...

Table 2. Size measurements on poly(amidoamine)PAMAM dendrimers (ethylenediamine core) from computer analysis of TEM images...

Three representative dendrimers, with different numbers of generations, are shown in Fig. 3.7-7. They are a poly(amidoamine) dendrimer (PAMAM) synthesized by D.A. Tomalia, which incorporates an ethylenediamine core and terminal amino groups (Fig. 3.7-7a), a poly(propyleneamine) product (POPAM) reported by... 

A variety of catalysts with differing aromatic substituents and ethylenediamine cores have been prepared and tested, but few perform better than Jacobsen s catalyst. These catalysts are not general for all alkene substrates and the best results have been achieved using cis-alkenes, trisubstituted alkenes and some tetrasubstituted derivatives. Especially high ees have been obtained with conjugated alkenes, in particular chromenes and P-substituted styrenes while trans-olefins and terminal olefins are poor substrates for this process. 

A bifunctional ligand was attached to different generation of ethylenediamine cored polyamidoamine dendrimer (PAMAM). Then Gl, G2 or G4 PAMAM dendrimer (8, 16 or 64 terminal primary amines) were mixed in water with an equimolecular amount of DOaAP 295c per number of primary amine (Scheme 62). Gd(III) and Gd(III)/Y(lll) complexes were prepared by mixing 2 equiv. of metal cation per thiourea function and removing the excess by washing with disodium EDTA [226, 227]. The reaction was extended to the fourth... 

Figure 11.7 Mathematical expressions for calculating the theoretical number of surface groups (Z), branch cells (BC), and molecular weights (MW) for [cystamine Core]-PAMAM dendrimers as a function of generation. Approximate hydrodynamic diameters (Gen = 0-7) based on gel electrophoretic comparison with the corresponding [Ethylenediamine Core]-PAMAM dendrimers. (Courtesy of reference [27])...

Poiyamido amine dendrimers Ethylenediamine or ammonia core, A/-(2-aminoethyl)acrylamide repeat units, seven generations M = 43 451 with ammonia core, 57 972 with ethylenediamine core. [260,261]... 

FIGURE 42.10. Approximate hydrodynamic diameters (Gen = 0-7) based on gel electrophoretic comparison with the corresponding [ethylenediamine core]-PAMAM dendrimers. 

Fig. 11 Dendritic branching mathematics for predicting the number of dendrimer surface groups, number of branch cells, and molecular weight. Calculated values are for [ethylenediamine core] lieniiri-poly(amidoamine) series with nanoscale diameters...

Jockusch J, Ramirez J, Sanghvi K, Nociti R, Turro NJ, Tomalia DA (1999) Comparison of nitrogen core and ethylenediamine core starburst dendrimers through photochemical and spectroscopic probes. Macromolecules 32 4419-4423... 

Table I Selected Molecular Characteristics of Ethylenediamine Core Poly(amidoamine) (PAMAM) Dendrimers...

Eig. 33. Ethylenediamine-core polyamidoamine-dendrimers 96 and 97. Redrawn, with permission, after Kobayashi... 

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