Biosensor technology in the treatment of cardiovascular disease - Biomaterials and Devices for the Circulatory System - page 279

11
Biosensor technology in the treatment of
cardiovascular disease

L. SHEDDEN, University of Strathclyde, UK

Abstract : This chapter describes the use of biosensors in the diagnosis
and treatment of cardiovascular disease. The main technical principles of
biosensor operation are introduced, followed by a review of current
applications, including clinical point of care and in vivo devices. Future
areas of biosensor development are discussed, including the interface
with tissue engineering and nanotechnology, and the potential use of
biosensors in implanted medical devices and home monitoring.

Key words : electrochemical biosensors, optical biosensors, point-of-care
testing, lab-on-a-chip, implanted sensors.

11.1 Introduction

The term 'biosensor' refers to a group of sensors that employ a range of
techniques for the detection of biochemical molecules from body fl uids
including blood and urine. The principle is the use of a biological recogni-
tion element coupled to a transducer to quantify a target analyte. The
development over recent years of a wide range of biosensor technology
allows the current detection of many analytes of interest to clinicians,
including glucose, lactate, cholesterol, urea nitrogen, creatinine, pH, blood
gases (oxygen, carbon dioxide, nitric oxide) and ions (sodium, potassium,
magnesium, calcium, chloride). Proteins, hormones and DNA can also be
detected. The main recognition elements employed are immobilised
enzymes, but specifi c ligand partners such as antibodies and oligonucle-
otides are also used in 'bioaffi nity' sensors (i.e. immuno- and DNA sensors).
The two main transducer types employed are electrochemical and optical
sensors. Electrochemical sensors convert the biological recognition events
to quantifi able electrical (amperometric or potentiometric) signals, while
optical sensors measure light absorption or output attributed to the reaction
between target molecule and recognition element. General biosensor oper-
ation is summarised in Fig. 11.1.
Biosensor technologies are being increasingly employed in medical
instrumentation, including clinical diagnostics and home testing kits, the
most common being the enzyme-based electrochemical glucose biosensor.
This chapter discusses current use of biosensors in the circulatory system;
in clinics, hospitals and surgery. It covers ex vivo applications, including

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