Lee and coworkers reported a pH-sensitive gold nanoparticle (AuNP) release
system. They used two kinds of γ-cyclodextrin (γ-CD). One was functionalized with
amine and dopamine (DOPA) on both rims (CD-NH 2 ). The dopamine side was
anchored to the AuNPs, and the amine side, providing a positively charged environment, was faced to another CD modified with 2,3-dimethyl maleic acid (DMA)
and chlorin e6 (Ce6) (CD-DMA), which was used as a negatively charged surface
molecule. DOPA-PEG, which also provided a positively charged environment, was a
component of this system, coupled to the surface of the AuNPs through DOPA
[75–77]. In most tumor microenvironments (pH 6.8) [78] the CD-DMA part would
be stimulated, leaving the CD-NH 2 part with the positive charge of the AuNPs,
causing tumor cells to extensively uptake the charged AuNPs (through interaction
with the negatively charged tumor cell membrane) [76]. This process would improve
the efficiency of light-driven tumor-specific photothermal therapy (PTT) and photodynamic therapy (PDT) because of the release of Ce6 from the AuNPs [79, 80],
resulting in induction of cell apoptosis or necrosis pathways. This process was
demonstrated in subsequent experiments by the authors [81] (Fig. 17).
Nitric oxide (NO) is a gaseous signaling molecule and a very important biological
messenger, controlling various biological processes in most organisms. Three scientists shared the 1998 Nobel Prize in Physiology or Medicine for discovering the role of
nitric oxide as a cardiovascular signaling molecule. NO also displays anticancer and
antibacterial activities in certain concentrations (these are dosage related); however, at
high concentrations it can be toxic to mammalian cells and tissues [82].
Hence, a lot of scientists are interested in design and synthesis of NO donors.
Sortino and coworkers developed a photoactivatable probe system containing
Fig. 14 Crowning β-cyclodextrin (β-CD) and vitamin E (VE) assembled nanoparticles, which
release VE under thermal control [60]
412
J. Liu et al.
system. They used two kinds of γ-cyclodextrin (γ-CD). One was functionalized with
amine and dopamine (DOPA) on both rims (CD-NH 2 ). The dopamine side was
anchored to the AuNPs, and the amine side, providing a positively charged environment, was faced to another CD modified with 2,3-dimethyl maleic acid (DMA)
and chlorin e6 (Ce6) (CD-DMA), which was used as a negatively charged surface
molecule. DOPA-PEG, which also provided a positively charged environment, was a
component of this system, coupled to the surface of the AuNPs through DOPA
[75–77]. In most tumor microenvironments (pH 6.8) [78] the CD-DMA part would
be stimulated, leaving the CD-NH 2 part with the positive charge of the AuNPs,
causing tumor cells to extensively uptake the charged AuNPs (through interaction
with the negatively charged tumor cell membrane) [76]. This process would improve
the efficiency of light-driven tumor-specific photothermal therapy (PTT) and photodynamic therapy (PDT) because of the release of Ce6 from the AuNPs [79, 80],
resulting in induction of cell apoptosis or necrosis pathways. This process was
demonstrated in subsequent experiments by the authors [81] (Fig. 17).
Nitric oxide (NO) is a gaseous signaling molecule and a very important biological
messenger, controlling various biological processes in most organisms. Three scientists shared the 1998 Nobel Prize in Physiology or Medicine for discovering the role of
nitric oxide as a cardiovascular signaling molecule. NO also displays anticancer and
antibacterial activities in certain concentrations (these are dosage related); however, at
high concentrations it can be toxic to mammalian cells and tissues [82].
Hence, a lot of scientists are interested in design and synthesis of NO donors.
Sortino and coworkers developed a photoactivatable probe system containing
Fig. 14 Crowning β-cyclodextrin (β-CD) and vitamin E (VE) assembled nanoparticles, which
release VE under thermal control [60]
412
J. Liu et al.