self-assembly in nature
Post on 02-Feb-2016
55 Views
Preview:
DESCRIPTION
TRANSCRIPT
Self-assembly in Nature
Nano
Self-assembly of amphiphilic molecules
vesicles (liposomes)
cylindrical micelles
nanotubes
spherical micelles
Drug delivery systems1. 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
HCl
1 10 100
3nm
18nm
Radius (nm)
DLS
pH 7
pH 5
pH drop
Vesicled = 36 nm
Micelled = 6 nm
pH 7 pH 5
0 50 100 150 200
0
20
40
60
80
100
pH drop to 5
Rel
ease
/ %
Time (h)
Release of Calcein
J. Am. Chem. Soc. 2004, 126, 12724
암세포에만 약물을 방출하는 나노 운반체
Carbohydrate – Protein Multivalent Interactions
Kiessling et. al. J. Am. Chem. Soc. 2002, 124, 14922.
Antigen
carbohydrate
antigen
Mannose-Coated Supramolecules
O
OH
O
HO
OH
O
OH
12
1
O
OH
O
HO
OH
O
OH
23
2
OHO
HOOH
HO
O
O
O
OHHO OH
O
O
O O
O
OHO
OH
OHHO
OH
O
O
O
HOOHHO
O
O
HO
3
J. Am. Chem. Soc. 2005, 127, 16333Chem. Commun. 2005, 2035J. Am. Chem. Soc. 2007, in press
50 nm
d= 40 nm
100 nm
d= 20 nm
100 nm
d= 10 nm
n.d.
glycocluster
lectin protein
0
200
400
600
800
1000
1200
1400
1600
1800
Rel
ativ
e ac
tivi
ty p
er m
ann
ose
Hemagglutination Inhibition Assay
Vesicle Sphere CylinderGalactose Micelle
Selective Binding of Supramolecules to Bacterial Cells
TEM
Binding toE. coli ORN 178
piliE. coli
E. coli
E. Coli (ORN 178) + spheres
100 nm 100 nm
E. Coli (ORN 178) + cylinders
100 nm
E. Coli (ORN 208)
Binding of Bacterial Cells
+
PathogenPathogenß-sheet assembly
O
HO
HO
HO
O
HO
=
= D-mannose-binding protein
Selective-binding
top related