Abstract: A DNA microarray system whereby measurement can be performed at a low running cost, a low price and yet a high accuracy. A nucleic acid probe (3) is immobilized on the surface of a gate insulator of an electric field effect transistor and then hybridized with a target gene on the surface of the gate insulator. A change in the surface electric charge density thus arising is detected by using the electric effect.

Abstract: A chemical analysis device capable of suppressing deterioration of analysis and test accuracy while avoiding contamination by residual samples or reagents and having no complicated configuration is constructed. A pipetting unit is equipped with a syringe, plunger, and needle unit in which a carrier for capturing nucleic acid and a detection cell is mounted on the needle unit. A pipetting unit drive system is configured so that the pipetting unit is detachable. After the detection cell is removed from the pipetting unit and fixed to a nucleic acid amplification detection unit, a suction/dispensing operation of samples/reagents is performed by the pipetting unit and components to be measured are captured by the carrier. Captured components are measured after being dispensed into the detection cell fixed to the nucleic acid amplification detection unit.

Abstract: A nucleic acid contained in a sample is quantified with high accuracy. The procedure includes the step of allowing the sample containing a specific nucleic acid to interact with a DNA microarray provided with a plurality of nucleic acid probe parts having a nucleic acid probe capable of hybridizing to the specific nucleic acid; the step of monitoring outputs from each of the plurality of nucleic acid probe parts due to hybridization between the nucleic acid probe and the specific nucleic acid to determine normal distribution of time taken to reach a predetermined output value with respect to each of the plurality of nucleic acid probe parts; and the step of quantifying the specific nucleic acid contained in the sample based on a maximum value determined from the normal distribution obtained in the above step.

Abstract: A nucleic acid contained in a sample is quantified with high accuracy. The procedure includes the step of allowing the sample containing a specific nucleic acid to interact with a DNA microarray provided with a plurality of nucleic acid probe parts having a nucleic acid probe capable of hybridizing to the specific nucleic acid; the step of monitoring outputs from each of the plurality of nucleic acid probe parts due to hybridization between the nucleic acid probe and the specific nucleic acid to determine normal distribution of time taken to reach a predetermined output value with respect to each of the plurality of nucleic acid probe parts; and the step of quantifying the specific nucleic acid contained in the sample based on a maximum value determined from the normal distribution obtained in the above step.

Abstract: A DNA microarray system whereby measurement can be performed at a low running cost, a low price and yet a high accuracy. A nucleic acid probe (3) is immobilized on the surface of a gate insulator of an electric field effect transistor and then hybridized with a target gene on the surface of the gate insulator. A change in the surface electric charge density thus arising is detected by using the electric effect.