Towards the Laboratory on a Chip
Abstract
Much attention has been devoted recently to the integration of miniature analytical systems on a single substrate, leading to what is often called the "laboratory on a chip." The aim is to automate all the fluid handling and assay procedures that are now still often done manually in biochemical or clinical assays. To do this we require a driving force to move fluids around on a chip. Two main types of driving forces have been investigated: fluid or pneumatic pressure, and (2) electroosmosis. The first option requires pumps and valves to provide or control the pressure, and these need to be miniaturized and integrated as well. This is a major task which is being tackled by many research groups; to date microvalves and pumps are still relatively large (3 to 10 mm on a side); have dead volumes in the microliter range; and the pumps are not usually self-priming. Another possibility is to use electroosmosis. This method has some key advantages that become stronger in the microdomain (channel dimensions in the tens of microns). First, the driving force is directly voltage. No valves are needed to switch fluid flow. Dead volumes are in the picoliter range, making possible sample volumes in the nanoliter range. Thus, this method accesses a range of volumes that microvalves and micropumps cannot reach. The achievable density of fluidic operations is very large, since channels and intersections typically have dimensions from 10 to 100 =B5m. To date, many applications of this technology have been demonstrated at Caliper, and elsewhere. We will discuss in more detail the precision mixing of components on-chip, binding assays, and DNA separations.
- Publication:
-
APS April Meeting Abstracts
- Pub Date:
- April 1997
- Bibcode:
- 1997APS..APR..M404B