Beyond Microtechnology—Nanotechnology in Molecular Diagnosis

Abstract

Advances in technology have led to significant improvements in our ability to detect and diagnose disease. In particular, the advent of nucleic acid technology has allowed unparalleled insight into the genetic basis of disease and a highly specific means to detect and diagnose infectious disease. A further technological advance, dating back to the 1980s, has been the use of microfabrication techniques widely utilized in the microelectronics imdustry to fabricate the use of microfabrication techniques widely utilized in the microelectronics industry to fabricate microminiaturized analyzers1,2. These devices have simplified and improved various steps in typical genetic test procedures, such as cell isolation and selection, nucleic acid extraction, amplification (PCR, RTR-PCR, LCR) and quantitation of nucleic acids (e.g., quantitative microchip capillary electrophoresis of PCR amplicons)3, 4, 5. More importantly integration of the analytical steps in nucleic acid assays can be achieved in a microchip format (lab-on-a-chip)6. For example, an integrated microchip was developed that performs cell isolation, cell lysis, nucleic acid purification and recovery in nanoliter volumes 7,8. Other microchips combine various steps such as DNA amplification and capillary electrophoresis9 or electrochemical detection10.