| Microfluidics may well be to the first half of the 21st century what microelectronics was to the latter half of the 20th century. The development of the integrated circuit allowed electrical devices to shrink from room-sized to pocket-sized, all the time increasing in speed and penetrating into nearly every aspect of our lives. Similarly, it is hoped that many of the large, expensive chemical and biological analyses currently being performed can be replaced by integrated microfluidic devices, often called labs-on-chip, resulting in a similar revolution. The scope of this thesis is best broken down into two parts. The first part will concentrate on the development of a theoretical and numerical framework for conducting microscale fluidic, thermal and biological simulation for electrokinetic processes and lab-on-chip devices. The analytical techniques and BLOCS (B&barbelow;io-L&barbelow;ab-O&barbelow;n-a-C&barbelow;hip S&barbelow;imulation ) numerical code developed as part of this effort are demonstrated through a series of examples ranging from enhanced species mixing to joule heating in polymeric microchips to DNA hybridization kinetics. The second part of the thesis concerns a microfluidics based and electrokinetically operated DNA hybridization chip. The chip development is detailed from the construction of a microfluidics/biochip test bench for chip operation, transport/thermal visualization and on-line hybridization detection, to the development of a rapid prototyping microfabrication facility through to the actual design, construction and operation of the device. The electrokinetic control of the chip and microfluidic implementation is shown to enable nanolitre scale samples to be dispensed to the hybridization array and allow for simultaneous hybridization, removal of non-specific adsorption and perform quantitative analysis all in less than 5 minutes. |
