Proceedings Article | 28 May 2009
KEYWORDS: Lab on a chip, Microfluidics, Liquids, Genetics, Acoustics, Biological research, Chemical analysis, Luminescence, Transducers, Analytical research
The collection, selection, amplification and detection of minimum genetic samples became a part of everyday life in
medical and biological laboratories, to analyze DNA-fragments of pathogens, patient samples and traces on crime
scenes. About a decade ago, a handful of researchers began discussing an intriguing idea. Could the equipment needed
for everyday chemistry and biology procedures be shrunk to fit on a chip in the size of a fingernail? Miniature devices
for, say, analysing DNA and proteins should be faster and cheaper than conventional versions. Lab-on-a-chip is an
advanced technology that integrates a microfluidic system on a microscale chip device. The "laboratory" is created by
means of channels, mixers, reservoirs, diffusion chambers, integrated electrodes, pumps, valves and more. With lab-ona-
chip technology, complete laboratories on a square centimetre can be created. Here, a multifunctional programmable
Lab-on-a-Chip driven by nanofluidics and controlled by surface acoustic waves (SAW) is presented. This system
combines serial DNA-isolation-, amplification- and array-detection-process on a modified glass-platform. The fluid
actuation is controlled via SAW by interdigital transducers implemented in the chemical modified chip surface. The
chemical surface modification allows fluid handling in the sub-microliter range. Minute amount of sample material is
extracted by laser-based microdissection out of e.g. histological sections at the single cell level. A few picogram of
genetic material are isolated and transferred via a low-pressure transfer system (SPATS) onto the chip. Subsequently the
genetic material inside single droplets, which behave like "virtual" beaker, is transported to the reaction and analysis
centers on the chip surface via surface acoustic waves, mainly known as noise dumping filters in mobile phones. At
these "biological reactors" the genetic material is processed, e.g. amplified via polymerase chain reaction methods, and
genetically characterized.
