Biomedical Engineering Reference
In-Depth Information
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Figure 5.19
Work function variation on the surface potential of a neuron when
forskolin is added to the medium.
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(Reprinted by kind permission of the Royal Society of Chemistry.)
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It is particularly interesting to note that these SKN results correlate with the
results obtained from acoustic wave detection outlined above. To further test
the real-time performance of the SKN in response to drugs, forskolin was
added at concentrations found to be biologically active in the acoustic wave
experiments.
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Remarkably, both SKN and TSM results correlate with a
classical enzyme-linked immunosorbent assay (ELISA) analysis for the
forskolin experiment.
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The addition of 10
4
M forskolin produces a large
300mV change in the surface potential of the neuron, as shown in Figure 4.19,
in precise correspondence with the acoustic and classic ELISA assays. From
such results, it is evident that the SKN is able to detect not only the presence of
neurons, but also the changes after the addition of specific drugs. It remains to
be established, however, what relationship exists between the observed
alterations in CPD and neuronal response to the drugs studied in these
experiments.
5.3 Future Possibilities in Cellular and Neuronal
Detection
Changes in the electrical and optical properties of cells, and of course neurons,
such as impedance, intensity of current, surface potential, refractive index,
interfacial evanescent wave propagation and work function can be measured
with very high accuracy using vibrational fields of different frequencies that are
intrinsically higher than conventional biological techniques. Analytical
methods based on vibrational fields can successfully complement the classical
