Abstract: Microfluidic devices having a diffusion-aided system for loading samples into the microfluidic device are provided. Methods of gas-venting a microfluidic device through a non-porous, gas permeable material sealing cover layer, for example, during liquid sample loading, are also provided. The non-porous, gas-permeable material can be, for example, a polysiloxane, for example, polydimethylsiloxane.

Abstract: 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.

Abstract: Methods for normalizing output from an instrument employing a reference standard or non-fluorescing substance disposed within at least one of a plurality of reaction chambers. The method comprises collecting and analyzing a signal associated with the reference standard or non-fluorescing substance to determine a normalizing bias. The normalizing bias is then applied to the data signal collected from a remainder of the plurality of reaction chambers.

Abstract: A method of conducting amplification comprising loading a liquid polynucleotide sample into a well of a microplate and covering the well of the microplate with a cover, such that the cover fluidly seals the liquid polynucleotide sample within the well. The method then comprises inverting the microplate such that the liquid polynucleotide sample contacts the cover; and thermocycling the microplate to promote amplification of polynucleotides in the liquid polynucleotide sample.

Abstract: An apparatus for normalizing a PCR instrument, can comprise a microplate comprising at least 6,000 wells and a system of dyes at known concentrations in a plurality of the at least 6,000 wells. A method for normalizing a system can comprise (a) providing a microplate comprising at least 6,000 wells and a system of dyes; (b) exciting at least one dye; (c) detecting an emission output for the at least one dye; (d) determining if the emission output is in an acceptable range; and (e) adjusting the system so that the emission output is in the acceptable range.

Abstract: A filling apparatus for filling a microplate. The microplate having a plurality of wells each sized to receive an assay. The filling apparatus can comprise an assay input layer having a first surface and an opposing second surface. The assay input layer can comprise an assay input port extending from the first surface to the second surface, a venting manifold formed in the second surface, and a vent hole in fluid communication with the venting manifold and atmosphere. An output layer can comprise a plurality of staging capillaries each having an inlet and an outlet. A venting layer can be disposed between the assay input layer and the output layer. The venting layer can comprise a plurality of microfluidic channels, a flow aperture being in fluid communication with the assay input port and the plurality of microfluidic channels, and a plurality of vent apertures each in fluid communication with at least one of the plurality of staging capillaries.

Abstract: A medical diagnostic device has a non-absorbent substrate that has a hydrophilic target area on which a reagent is deposited by non-impact printing of microdroplets. During deposition, the device is moved relative to the stream of microdroplets to form a substantially uniform reagent layer on the substrate. The device is particularly well adapted for measuring blood coagulation times. In a preferred embodiment, coagulation times are determined by monitoring the optical transmission of light through the target area as an applied blood sample interacts with the reagent.

Abstract: A medical diagnostic device has a non-absorbent substrate that has a hydrophilic target area on which a reagent is deposited by non-impact printing of microdroplets. During deposition, the device is moved relative to the stream of microdroplets to form a substantially uniform reagent layer on the substrate. The device is particularly well adapted for measuring blood coagulation times. In a preferred embodiment, coagulation times are determined by monitoring the optical transmission of light through the target area as an applied blood sample interacts with the reagent.

Abstract: A medical diagnostic device has a non-absorbent substrate that has a hydrophilic target area on which a reagent is deposited by non-impact printing of microdroplets. During deposition, the device is moved relative to the stream of microdroplets to form a substantially uniform reagent layer on the substrate. The device is particularly well adapted for measuring blood coagulation times. In a preferred embodiment, coagulation times are determined by monitoring the optical transmission of light through the target area as an applied blood sample interacts with the reagent.

Abstract: A medical diagnostic device has a non-absorbent substrate that has a hydrophilic target area on which a reagent is deposited by non-impact printing of microdroplets. During deposition, the device is moved relative to the stream of microdroplets to form a substantially uniform reagent layer on the substrate. The device is particularly well adapted for measuring blood coagulation times. In a preferred embodiment, coagulation times are determined by monitoring the optical transmission of light through the target area as an applied blood sample interacts with the reagent.

Abstract: A fluidic medical diagnostic device permits measurement of analyte concentration or a property of a biological fluid, particularly the coagulation time of blood. The device has at one end a sample port for introducing a sample and at the other end a bladder for drawing the sample to a measurement area. A first channel carries the sample from the sample port to the measurement area, and a stop junction, between the measurement area and bladder, halts the sample flow. A second channel, which runs from the first channel to an edge of the device, determines whether the sample volume is sufficient to permit an accurate measurement. The desired measurement can be made by placing the device into a meter, which measures a physical property of the sample, typically optical transmittance, after it has interacted with one or more reagents on the device.