Partitioned microelectronic device array

A method of assaying nucleic acid which comprises separately and in parallel for each of two or more nucleic acid-containing samples:

• placing a first nucleic acid-containing sample and a second nucleic-acid-containing sample into an array comprising a solid substrate, a plurality of wells and channels, wherein at least one channel is formed in the upper surface of the substrate and is situated above another channel formed in the lower surface of the substrate, so as to form crossovers comprising crossing but non-intersecting channels;
• moving said first sample into a first well for isolating nucleic acid;
• moving said second sample into a second well for isolating nucleic acid;
• moving the isolated nucleic acid from the first sample to a third well;
• moving the isolated nucleic acid from the second sample to a fourth well;
• amplifying the nucleic acid in the third and fourth wells by cycling the temperature of the third and fourth wells;
• moving the amplified nucleic acid in the third well to a fifth well for assay;
• moving the amplified nucleic acid in the fourth well to a sixth well for assay;
• and
• assaying the amplified nucleic acid.