Interfacing Biomolecules, Cells and Tissues with Nanowire-based Electrical Devices - Applications of Electrochemistry and Nanotechnology in Biology and Medicine - page 100

frequency, much greater amplitude, and longer duration ( Fig. 9C ,
II , green stars). These new peaks, which are coincident with cell
beating, rapidly reached a steady state ( Fig. 9C, III ) with an aver-
age calibrated peak amplitude of ~80 mV and duration of ~200 ms.
The amplitude, sign, and duration are near those reported for
whole-cell patch clamp recordings from cardiomyocytes, 42,53 and
thus it was concluded that these data represent a transition to
steady-state intracellular recording with the 3D nanowire probe.
When the PDMS/cell substrate was mechanically-retracted from
the 3D kinked nanowire devices, the intracellular peaks disap-
peared, but reappeared when the cell substrate was brought back
into gentle contact with the device.
Additional work remains in order to develop this new synthet-
ic nanoprobe as routine tool like the patch-clamp micropipette, 54
although we believe that there are already clear advantages: Elec-
trical recording with kinked nanowire probes is relatively simple
without the need for resistance or capacitance compensation, 55 the
nanoprobes are chemically less invasive than pipettes as there is no
solution exchange, the small size and biomimetic coating minimiz-
es mechanical invasiveness, and the nanoFETs have high spatial
and temporal resolution for recording.
VIII. CONCLUSIONS
We have shown that NW-based field-effect sensor devices repre-
sent a powerful detection platform for a broad range of biological
and chemical species in solution. The examples described in this
chapter show clearly the potential of NW-based field-effect sensor
devices to significantly impact disease diagnosis, drug discovery,
neurosciences, as well as serve as powerful new tools for research
in many areas of biology and medicine. We believe that these ad-
vances could be developed at the commercial level in simple NW
sensor devices and probes that would represent a clear application
of nanotechnology, and, more importantly, a substantial benefit to
humankind.