Miniaturized Detection Systems - Waterborne Pathogens: Detection Methods and Applications - page 308

CHAPTER TEN
Miniaturized Detection Systems
Helen Bridle
Heriot-Watt University, Institute of Biological Chemistry, Biophysics and Bioengineering, Riccarton,
Edinburgh, Scotland
Previous chapters have covered a range of detection techniques, covering
optical, electrical, and molecular methods as well as biosensors. Chapter 9
looked at the ways in which nanotechnology could improve these methods.
This chapter will focus on the role that miniaturization, in particular using
microfluidic systems, can play in the delivery of “lab-on-a-chip” devices to
perform the detection procedures previously described.
The chapter starts with an introduction to the field of microfluidics,
covering microfabrication, the underlying fluid mechanics and the types
of components which can be incorporated to deliver more complex fluid
handling capability. Next, the chapter presents how microfluidic devices can
be utilized to enhance the performance of the detection methods proposed
in Chapters 5-8. Particular attention will be devoted to examples concern-
ing waterborne pathogens.
10.1. MICROFLUIDICS
Microfluidic systems, i.e. fluid handling systems with dimensions on
the micrometer scale, have developed rapidly during the past decade and
have found many applications, especially within chemical analysis and bio-
logical assays. This is unsurprising considering their numerous advantages
which include reduced sample consumption, increased speed of analysis,
improved efficiency, and process parallelization as well as access to phenom-
ena and mechanisms that are not accessible on the macroscopic scale. 1
Microfluidics is an enormous field and thus it is impossible to review
fully here; this chapter describes briefly the microfabrication of microfluidic
devices, specifically focusing upon devices manufactured in polydimethylsi-
loxane (PDMS) as this offers a way of rapid, and relatively cheap prototyp-
ing, the fluid mechanics governing device function and the incorporation
of components, such as valves, mixers, and methods of temperature control
( Fig. 10.1 ).