Polyamidoamine dendrimers and

Synthetic polymer. Among the cationic synthetic polymers used for gene delivery are polyethylenimine (PEI), polyamidoamine dendrimers, and poly(2-dimethylaminoethyl methacrylate).161-164 Depending on the flexibility (or rigidity) of the polymers, they form either a small (<100 nm) DNA polyplex or a large (>1 to 10 pm) DNA polyplex.165 More detailed physicochemical properties and their transfection efficacy are to be discussed. 

H. Yang, S.T. Lopina, Extended release of a novel antidepressant, venlafaxine, based on anionic polyamidoamine dendrimers and poly(ethylene glycol) containing semi-interpenetrating networks, J. Biomed. Mater. Res. A 72 (2005) 107-114. 

Trehalose tetraesters characterised by ID and 2D H and C NMR and ESI-MS as biosurfactants (rather than cryoprotectants) were isolated from a soil strain of Micrococcus luteus. Solubilisation of phenol within mieellar aggregates of hexadecyltrimethylammonium bromide (HTAB) in aqueous solutions were investigated by H NMR in D20. The synthesis and properties of non-cytotoxic carboxymethylcellulose-chitosan hydrogels modified with poly(ester-urethane) was reported. 2D NOE NMR gave new insights into the interactions between polyamidoamine dendrimers and different surfactants including SDS and dodecyltrimethylammonium bromide. The ability of a- and (3-CDs to disrupt a surfactant mixed micelle of an equimolar mixture of octyltriethylammonium bromide (OTEAB) and sodium perfluorooctanoate (SPFO) was studied by H and F NMR. The effect of ethanol on the micellization of SDS (anionic... 

Tanaka, H.. Hashimoto, T, Koizumi, S., Itoh, H., Naka, K., and Chujo, Y. (2008) Control of self-assembling processes of polyamidoamine dendrimers and Pd nanopartides. Macromolecules, 41, 1815-1824. 

The first true dendrimers were the polyamidoamines (PAMAMs). They are also known as starburst dendrimers, and the term starburst is a trademark of the Dow Chemical Company, who have commercialized these materials for a range of applications. These dendrimers use ammonia as the core molecule, and this is reacted with methyl acrylate in the presence of methanol, after which ethylenediamine is added. This is shown in Scheme 9.2. 

L. Shen and N.F. Hu, Heme protein films with polyamidoamine dendrimer direct electrochemistry and electrocatalysis. BBA-Bioenergetics 1608, 23—33 (2004). 

Tomalia, D. A. and Dvornic, P. R. Dendritic polymers, divergent synthesis (starburst polyamidoamine dendrimers) , in Salamone, J. C. (ed.), Polymeric Materials Encyclopedia, Vol. 3, CRC Press, Boca Raton, FL, 1996, pp. 1814-1830. 

Arima, H., F. Kihara, F. Hirayama, and K. Uekama. 2001. Enhancement of gene expression by polyamidoamine dendrimer conjugates with alpha-, beta-, and gamma-cyclodextrins. Bioconjug Chem 12(4) 476-84. 

I,ee 1, Athey BD, Wetzel AW, Meixner W, Baker JR Jr. Stmctural molecular dynamics studies on polyamidoamine dendrimers for a therapeutic application effects of pH and generation. Macromolecules 2002 35 4510-4520. 

Devarakonda et al. (2005) compared the solubilization of niclosamide by complexing with polyamidoamine (PAMAM) dendrimers and CDs, and found the solubility of niclosamide was sig-niLcantly higher with PAMAM. However, the dissolution rate was lower with PAMAM compared to the CDs, which was owing to the strong interaction between niclosamide and PAMAM delayed the release of the drug from the complexes of dendrimers. 

Devarakonda, B., Hill, R. A., Liebenberg, W., Brits, M., and de Villiers, M. M. 2005. Comparison of the aqueous solubilization of practically insoluble niclosamide by polyamidoamine (PAMAM) dendrimers and cyclodextrinslnt. J. Pharm. 304 193-209. 

Polyamidoamine Dendrimer, primary amino In vitro and in vivo (Haensler and Szoka, 1993 ... 

Kukowska-Latallo, J.F., Bielinska, A.U., Johnson, J., Spindler, R., Tomalia, D.A. and Baker, Jr., J.R. (1996) Efficient transfer of genetic material into mammalian cells using Starburst polyamidoamine dendrimers. I roc. Natl. Acad. Sci. USA, 93,4897-4902. 

Hudde, T., Rayner, S.A., Comer, R.M., Weber, M., Isaacs, J.D., Waldmann, H., Larkin, D.F.P. and George, A.J.T. (1999) Activated polyamidoamine dendrimers, a non-viral vector for gene transfer to the corneal endothelium. Gene Ther., 6, 939-943. 

Tang, M.X., Redemann, C.T. and Szoka, F.C. (1996) In vitro gene delivery by degraded polyamidoamine dendrimers. Bioconjug. Chem., 7, 703-714. 

Malik, N., et al. 2000. Dendrimers Relationship between structure and biocompatibility in vitro, and preliminary studies on the biodistribution of 1251-labelled polyamidoamine dendrimers in vivo. 

Polyamidoamine (PAMAM) dendrimers are non-linear polycationic cascade polymers that can bind plasmid DNA [43]. The interaction of activated PAMAM-dendrimers and plasmid DNA induces condensation of the nucleic acid. The compact transfection complexes can subsequently adhere to the cell surface and be taken up by endocytosis. 

For asymmetric monodendrons, an increase in compression resulted in collapse of the dendrimer and the formation of a bilayer structure with the macromolecules compressed laterally with respect to the surface normal, with an axial ratio of 2 1. This situation is illustrated in Fig. 4.13. These dendritic macromolecules are flexible enough to assume a prolate conformation under modest lateral compression in a Langmuir trough. Polyamidoamine (PAMAM) dendrimers [109] were also used by Tsukruk et al. [110] to fabricate self - assembled monolayers. The thickness of all the monolayers were much smaller than the diameter of dendritic macromolecules in solution. This behavior can indicate collapse of the dendritic macromolecules, which become highly compressed along the surface normal and flattened. (See Fig. 4.13b). 

On-chip chiral separation of enantiomers of adrenaline, noradrenaline, and dopamine was achieved using a mixture of carboxymethyl-p-cyclodextrin (CMCD) and a polyamidoamine dendrimer (Starburst) [120], On-chip chiral separation of enantiomers of homovanillic acid, DOPA, cDOPA, methoxy-tyramine (MT), metanephrine, and normetanephrine was achieved using a mixture of 18-crown-6-ether and carboxymethyl-P-cyclodextrin [120],... 

---