Biomedical Engineering Reference
In-Depth Information
(A)
(B)
Primary
Ab
Gold
nanoparticles
Heated
zones
Au
Secondary
Ab
Au
Surface
protein
ll
Bubbles
Cancer cell
Cancer cell
FIGURE 19.1
Principle of selective nanophotothermolysis of cancer cells targeted with gold
nanoclusters. (A) The human adenocarcinoma cell targeted with primary
antibodies (Abs), which are selectively attached to surface proteins; secondary
Ab goat antimouse IgG, conjugated with 40-nm gold nanoparticles, is selectively
attached to the primary Abs. (B) The schematics of laser-induced overlapping of
heated zones and bubbles from the nanoparticles attached to cell membrane.
Source: From Ref. [
27
].
19.7.1
Gold Nanoparticles for Anticarcinogenic Drug Delivery
Colloidal gold nanoparticles are the most commonly used nanoparticles for anticarcinogenic drug
delivery. Colloidal gold nanoparticles are more biocompatible than other nanoparticles. The physical
and chemical properties of colloidal gold nanoparticles allow more than one protein molecule to bind
to a single particle of colloidal gold. The use of colloidal gold nanoparticles as drug delivery vectors
of tumor necrosis factor (TNF) has been tested in a growing tumor in mice
[25]
. Although TNF has
been evaluated in cancer treatment, it causes adverse effects such as hypotension and, in some cases,
organ failure, resulting in death. But recent researches have shown that when coupled with colloid
gold particles, therapeutic amounts of TNF can be successfully delivered to destroy the tumor cells in
animals
[26]
. The use of laser to destroy the tumor cells in cancer tissue has been described by a tech-
nique using selective nanothermolysis of self-assembling gold nanoparticles
[27]
(
Figure 19.1
). These
gold nanoparticles were coated with secondary antibody goat antimouse immunoglobulin G (IgG).
This structural configuration showed specific localization in the adenocarcinomatous cells targeted
with primary antibody. The targeted photothermal therapy has been tested
in vitro
toward killing the
oral squamous carcinoma cells
[28]
. Epidermal growth factor or EGF is a growth factor that plays
an important role in the regulation of cell growth, proliferation, and differentiation by binding to its
receptor, EGFR. Because of the increased risk of cancer by EGF, inhibiting it decreases cancer risk.
Such approaches are aimed at inhibiting the EGFR. In this study
[28]
, two oral squamous carcinoma
cell lines and one benign epithelial cell line were incubated with anti-EGFR antibody-conjugated
gold nanoparticles and then exposed to continuous visible argon ion laser at 514 nm. It was found
that the malignant cells required less than half the laser energy to be killed than the benign cells after
incubation with anti-EGFR antibody-conjugated gold nanoparticles. No photothermal destruction was
