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CHE5480 Summer 2005. Dendrimers June 14, 2005. Starburst Dendrimers. What is a dendrimer? Branched polymers ( dendron = tree in Greek) Functionality = 3 (Nitrogen). Silicon, Si, functionalty f=4. Rose bengal inside PPI dendrimer. Dendrimers:. 1. Manufacture 2. Structure
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CHE5480 Summer 2005 Dendrimers June 14, 2005
What is a dendrimer? Branched polymers(dendron = tree in Greek)Functionality= 3 (Nitrogen)
Dendrimers: • 1. Manufacture • 2. Structure • 3. Characterization • 4. Applications
Manufacture: • (i) Divergent Method • (ii) Convergent Method
Generations of Dendrimers Your Text Here
Generations of Dendrimers 2nd gen. 5th gen. 4th gen.
PAMAM Dendrimer (polyamidoamine) • Alternating (B)-AB-AB-AB-... • Ethylenediamine (B) • H2N-C-C-NH2 • Methylacrylate (A) • C=C-CO-OCH3
PAMAM Moieties: Diamine Acrylate NH3 or Diamine
f=3 fc=3 1 2 3 generations Spacer b
Construction of Generations: • Core: Ethylenediamine (Moiety B = D) • “Michael Addition” of 4 Methylacrylates (A= O) • Amidization: add 4 ethyldiamines (D) • Result: Generation “0”
Continue Branching: Generation “1”:
Calculations: • Note that • Core functionality (2 nitrogens): fc = 4 • Branch functionality (nitrogen): f=3 • No. of Spacers (A+B): b=2 • Generation = G
Applications of Dendrimers • Gas and chemical sensors • Catalysts • Drug delivery and gene therapy • Surface modifiers (tribology, and information storage) • Bio compatible materials • Electronic devices and antennae
Size of PAMAM DendrimersGeneration M.W. Angstrom (dia.) End Gps (1 nm = 10 Angstroms)