Biomedical Engineering Reference
In-Depth Information
The results provided clear images and suggested that, by incorporating
further functional groups and/or species, the complexes could act as both
targeting agent and biosensing devices. In addition, through NIR irradiation
upon application of an external magnetic ield, the complexes could induce
phototherapy and hyperthermia in cells.
9.2.5.2 Single-parcletracking
Single-particle tracking by individual SWCNTs using their NIR band gap
luorescence represents an interesting strategy to understand how this
carbon-based material interacts with several molecules, including living
systems. This methodology was initially developed by the R. B. Weisman
laboratory at Rice University, and it still represents one of the few available
tools to study individual SWCNT molecules in solution over a prolonged time,
since SWCNTs have no apparent irreversible photobleaching effect and no
intrinsic blinking mechanism.
144
Recent advances have enabled real-time
measurement of tubes' physical characteristics (e.g., length) and mechanical
properties, while combined translational and rotational measurements
revealed the inluence of local environment on nanotube mobility.
145
Moreover, single-particle tracking of SWCNTs intrinsic photoluminescence
was used to map the trajectories of the tubes, as they were internalised
inside and expelled from NIH-3T3 cells in real time.
146
The authors found
that cellular uptake of SWCNTs was nearly 1,000 times faster than the rate
of Au nanoparticles reported in literature; conversely, nanotubes exocytosis
showed an expulsion rate that matched the endocytotic process. Moreover, the
experiments were associated with a detailed evaluation of the trajectories of
CNTs in their internalisation pathway:
147
over 10,000 individual trajectories
of non-photobleaching SWCNTs were tracked as they were incorporated
into and expelled from NIH-3T3 cells in real time on a perfusion microscope
stage. The subsequent analysis of the mean square displacement allowed the
complete construction of the mechanistic steps involved. Data collected from
this study allowed to justify the observed accumulation of SWCNTs inside the
cells via endocytotic and exocytotic pathways. In addition, the study provided
useful information for the design of future systems with lower toxicity and
improved eficacy.
9.2.6 Mexico
TERRONES (Humberto & Mauricio)
@ Advanced Materials Department, IPICYT, Mexico
excellence/chairs_excellence_09/mauricio_terrones
Expertise: Functionalisation and electrical properties of carbon
nanotubes
Search WWH ::
Custom Search