Biomedical Engineering Reference
In-Depth Information
(e.g., malignant melanoma) [105, 281, 282]. (RGDyK) peptide-coated magnetite
nanoparticles have also been shown to accumulate preferentially in the integrin
α
3
- rich tumor area [283] .
Antibodies directed against several types of cancer marker have been conjugated
to magnetic nanoparticles, and the conjugates used as MRI contrast agents
in vitro
and
in vivo
[100, 284-287]. The use of superparamagnetite particles coated with
monoclonal antibodies directed against epidermal growth factor receptors (EGFRs),
has allowed the high-contrast MRI imaging and diagnosis of squamous cell carci-
noma of the esophagus [285]. MRI using contrast agents based on magnetic
nanoparticles coated with polypeptide functionalized with monoclonal antibodies
specifi c to carcinoembryonic antigen [287] and the therapeutic antibody Erbitux
[286] have also been reported. Several biofunctionalized PEG-coated magnetic
nanoparticles (including magnetic liposomes) have been successfully employed
as contrast agents for cancer MRI [98, 100, 288]. For example, PEG-coated mag-
netite nanocrystals, which were functionalized with a specifi c cancer - targeting
antibody, have been used as contrast agents for tumor detection in live mice by
MRI (Figure 4.9 ) [100] .
V
β
Antibody
O
O
Fe
3
O
4
O
O
O
O
n
Tumor
Before
10
min
6
h
10
h
24
h
Figure 4.9
PEG - coated antibody - functionalized magnetic
nanoparticles as MRI contrast agents for cancer detection
(top).T
2
*
-weighted MR images acquired before and at different
times after injection of Fe
3
O
4
- (rch 24 mAb) conjugates
(bottom). Reproduced from Ref. [100] .
