Self-assembly in Nature

Nano

Self-assembly of amphiphilic molecules

spherical micelles cylindrical micelles nanotubes vesicles (liposomes)

Drug delivery systems Direct conjugation of drugs or therapeutic proteins to macromolecules such as polymers and proteins.

2. Encapsulation of hydrophobic drugs at the inside of the micelles or dendrimers

3. Entrapment of water-soluble drugs at the inside cavity of vesicles

The enhanced permeability and retention (EPR) effect Macromolecules cannot pass through the capillary walls of normal tissue. The entry of macromolecules into tumor tissue takes place in the capillaries where blood flow is diminished and nutrients transfer into the tissue. In contrast to the blood capillaries in most normal tissues, the endothelial layer of the capillaries in the tumor tissue is fenestrated and leaky so that macromolecules and other nanoparticles reach the malignant tissue. Tumor tissue generally has a defective lymphatic drainage system with the result that macromolecules are retained and can subsequently accumulate in solid tumors.

pH-Responsive Nanocapsules 1 10 100 3nm 18nm Radius (nm) DLS pH 7 pH 5 HCl pH drop Vesicle d = 36 nm Micelle d = 6 nm pH 7 pH 5 Release of Calcein J. Am. Chem. Soc. 2004, 126, 12724

암세포에만 약물을 방출하는 나노 운반체

Carbohydrate – Protein Multivalent Interactions Antigen antigen carbohydrate Kiessling et. al. J. Am. Chem. Soc. 2002, 124, 14922.

Mannose-Coated Supramolecules n.d. glycocluster lectin protein Hemagglutination Inhibition Assay Vesicle Sphere Cylinder Galactose Micelle 12 1 23 2 3 50 nm d= 40 nm 100 nm d= 20 nm d= 10 nm J. Am. Chem. Soc. 2005, 127, 16333 Chem. Commun. 2005, 2035 J. Am. Chem. Soc. 2007, in press

E. Coli (ORN 178) + cylinders Selective Binding of Supramolecules to Bacterial Cells TEM Binding to E. coli ORN 178 pili E. coli E. Coli (ORN 178) + spheres 100 nm E. Coli (ORN 178) + cylinders E. Coli (ORN 208)

+ Binding of Bacterial Cells = Selective-binding Pathogen ß-sheet assembly = D-mannose-binding protein Selective-binding