Biosensors and Biodetection

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Biosensors and Biodetection
Methods and Protocols
Volume 503: Optical-Based Detectors
Avraham Rasooly and Keith E. Herold
2009
pages 452

توضیحات

Biosensors and Biodetection

In recent years, many types of biosensors have been developed and used in a wide
.variety of analytical settings, including biomedical, environmental, research, and others
A biosensor is defined by the International Union of Pure and Applied Chemistry
(IUPAC) as a “device that uses specific biochemical reactions mediated by isolated
enzymes, immunosystems, tissues, organelles, or whole cells to detect chemical compounds
usually by electrical, thermal, or optical signals” (۱). Thus, almost all biosensors
are based on a two-component system: a biological recognition element (ligand)
that facilitates specific binding to or biochemical reaction with a target, and a signal
conversion unit (transducer). Although it is impossible to fully cover the fast-moving
field of biosensing in one publication, this publication presents some of the many
types of biosensors to give the reader a sense of the enormous potential for these
.devices
,An early reference to the concept of a biosensor is from Dr. Leland C. Clark
”who worked on biosensors in the early 1960s (2) developing an “enzyme electrode
for glucose concentration measurement with the enzyme glucose oxidase, a measurement
that is important in the diagnosis and treatment of disorders of carbohydrate
metabolism in diabetes patients. Still today, the most common biosensors used are for
.glucose analysis
A large number of basic biosensors, all combining a biological recognition element
and a transducer, were subsequently developed. Currently, the trend is toward
.more complex integrated multianalyte sensors capable of more comprehensive analyses
Advances in electronics and microelectrical and mechanical systems (MEMS) have
enabled the miniaturization of many biosensors and the newest generation biosensors
include miniaturized multianalyte devices with high-throughput capabilities and more
.than 1,000 individually addressable sensor spots per square centimeter
A useful categorization of biosensors is to divide them into two groups: direct recognition
sensors, in which the biological interaction is directly measured, and indirect
detection sensors, which rely on secondary elements for detection. Figure 1 shows a
schematic of the two groups of biosensors. In each group, there are several types of
,transducers including optical, electrochemical, and mechanical. For all of these technologies
the recognition ligand plays a major role. Although the most commonly
used ligands are antibodies, other ligands are being developed including aptamers
.(protein-binding nucleic acids) and peptides