Development of a microchamber array for picoliter PCR.

A microchamber array for PCR was developed by semiconductor microfabrication technology. The microchambers were designed to be of picoliter quantity. To optimize fluid retention, the surface states of the substrate and the inner walls were examine for four different types of microchamber. The substrate was silicon, while silicon dioxide was selected for the inner walls. PCR was performed in the microchamber array, and the amplification of DNA was detected using a technique based on the energy transfer of fluorescent dyes. The lower volume limit for PCR was investigated using various sizes of microchambers. Microchambers with volume greater than 86 pL gave successful PCR. In addition, the system was improved in order to take up the PCR product. To prevent mixing of the samples, the samples were dried after PCR using a membrane that permeates only vapor.