Application of a microchamber array for DNA amplification using a novel dispensing method.

We recently developed a microchamber array chip for DNA amplification by adopting semiconductor microfabrication technology; a polymerase chain reaction (PCR) was performed in the microchamber array, and the amplified DNA was detected using a fluorescent dye. In order to manipulate a single cell or sample into each microchamber individually in this system, the chip was directly sealed with a cover glass slip which impeded the retrieval of the products from each chamber. The present study was therefore carried out to improve the system by developing methods for covering the microchambers and introducing the reaction solution. First, we fabricated a microchamber array chip, and the oil layer was coated on the whole chip instead of the cover glass slip. The solution for DNA amplification was introduced into each chamber through an oil layer using a nano-liter dispenser. Following this, the microarray chip was placed onto the thermal cycling system for DNA amplification, and the amplified DNA was subsequently detected by fluorescence microscopy. In this system, the products were easily retrieved using a micromanipulator for further analysis.