Biosensor technology in the treatment of cardiovascular disease - Biomaterials and Devices for the Circulatory System - page 296

The application of nanomaterials and systems (dimensions less than 100 nm)
has the potential to contribute to various aspects of biosensor technology,
including signal transduction and in vivo sensors. Detection of proteins,
peptides and DNA can be enhanced by the binding of nanoprobes (nanopar-
ticles including gold, platinum and copper) to the target molecules. Nano-
tubes (made mainly of carbon, but also of gold and polypyrrole) act as
molecular wires and can offer direct electron transfer to enhance electro-
chemical and optical biosensors.
Nanofabrication techniques can be used to produce nanoscale devices,
which may be of particular interest for continuous monitoring in the circula-
tory system using implanted devices. Technical challenges associated with
the implementation of nanotechnology-based biosensors include the inte-
gration with auxiliary sensor functions, such as fl uid handling, sampling and
separation. 58 The toxicology of nanomaterials needs to be assessed thor-
oughly; carbon nanotubes in certain forms have been shown to be damaging
to the cells lining the lungs, in a similar way to asbestos, in a mouse model. 59
Whole cell biosensors, as discussed above, may provide the ideal system
for testing the toxicity of nanomaterials.

11.8 Conclusions

This chapter summarises the main methods by which biosensors operate,
and some of the ways in which such sensors are being used in and around
the cardiovascular system. Many other biosensor technologies are available
or in development that have not been discussed here, and the fi eld of bio-
sensors is of large and growing research and clinical interest. Currently
biosensors are of use in a wide number of settings and applications. Patients
with chronic diseases such as diabetes rely on biosensor-based devices that
they can use at home and interpret themselves for the long-term manage-
ment of their conditions. In hospitals, point-of-care and in vivo devices
allow patient analytes to be assessed rapidly, giving clinicians valuable
information to make timely decisions on patient care. Biosensors are
involved in analysing DNA, with the aim of identifying an individual's risk
of suffering from, for example, coronary artery disease. They also contrib-
ute to the fi eld of tissue engineering, which has the potential to have a
signifi cant impact in repair/replacement in the cardiovascular system.
There is a growing clinical need for biosensors. It has become standard
over recent years for diabetics to self-monitor their glucose levels using
technology containing biosensors. This situation is likely to become the
norm for people with other chronic conditions, including diseases of the
cardiovascular system. Telemedicine is gaining popularity, and it is likely
in the future that more patients will have their conditions remotely moni-
tored, without having to make regular trips to hospitals for check-ups. This

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