HO
NH 2
O
NH 3
O
H 2 N
O
Cysteine
capped
ZnS QD
O
O
O
HO
NH
HO
O
OH
OH
O
n
x
NH 2
O O
O
HO
NH
HO
O
OH
OH
O
n
x
Chitosan
Cysteine
capped
ZnS QD
N 2 gas
(1)
(2)
(3)
Heat at 80°C
for 25 min
S
S
L-cysteine-functionalized
ZnSQD-chitosan
nanocomposite
L-cysteine-functionalizedZnSQD
O
O
O
OH
OH
HO
HO
O
NH2
NH
O
n
x
SH
HO
O
O
O
O
OH
OH
HO
HO
O
NH
O
n
x
SH
NH
O
SOCl2, 72° C, 24 h
4 carboxylicthiophenol, 95° C
O
O
O
OH
OH
HO
HO
O
NH
O
n
x
SH
NH
O
HAuCl4/PVP/ 2-propanol
Acetic Acid, -irradiation
Chitosan
(a) Preparation of quantum dot (QD)
(b) Chitosan-GNP derivative
Fig. 1 (continued)
Functionalized Nanoparticles and Chitosan-Based Functional Nanomaterials
35