An inverted microplate for conducting a thermocycled amplification reaction of polynucleotide. The microplate can comprise a main body having a first and second surfaces and a plurality of wells disposed in the first surface. Each of the plurality of wells can comprise a well opening and a well bottom and be sized to receive an assay. A sealing cover can be operably coupled to the first surface of the main body to seal the well openings of the plurality of wells when the main body is inverted so that the assay is in contact with the sealing covering cover.