Miniaturization of analytical systems.

Miniaturization has been a long-term trend in clinical diagnostics instrumentation. Now a range of new technologies, including micromachining and molecular self-assembly, are providing the means for further size reduction of analyzers to devices with micro- to nanometer dimensions and submicroliter volumes. Many analytical techniques (e.g., mass spectrometry and electrophoresis) have been successfully implemented on microchips made from silicon, glass, or plastic. The new impetus for miniaturization stems from the perceived benefits of faster, easier, less costly, and more convenient analyses and by the needs of the pharmaceutical industry for microscale, massively parallel drug discovery assays. Perfecting a user-friendly interface between a human and a microchip and determining the realistic lower limit for sample volume are key issues in the future implementation of these devices. Resolution of these issues will be important for the long-term success of microminiature analyzers; in the meantime, the scope, diversity, and rate of progress in the development of these devices promises products in the near future.