This is the first report of a polymerase chain reaction (PCR)-based Mycobacterium tuberculosis diagnostic tool fabricated as a silicon microreactor for DNA amplification using a halogen lamp as the heating source. Our experiments demonstrate that PCR amplification can be successfully performed in silicon microreactors using a non-contact heating method. These devices have been used to amplify a specific fragment of the rpoB gene from M. tuberculosis, where mutations leading to multi-drug resistant strains are most likely to occur. Amplification was achieved in the microreactors in 34 min, compared to the 62 min amplification time required in a conventional peltier-heated PCR machine. Temperature control accuracy for our heating approach was +/-1 degreesC. The amplification was performed from genomic DNA and produced PCR products in comparable quantities to a conventional thermal cycler, but in reduced time. This paper describes the fabrication, characterisation, control and use of these prototype devices for DNA amplification. PCR conditions were established using Lambda bacteriophage DNA as a model reaction system. Subsequently, DNA from the M. tuberculosis rpoB gene was successfully amplified. (C) 2004 Elsevier B.V. All rights reserved.