Method and Apparatus for Melting Curve Analysis of Nucleic Acids in Microarray Format

A microarray cassette assembly for use in an apparatus for conducting a melting curve analysis of nucleic acids, the microarray cassette assembly comprising:

• a frame, having an opening including an inside perimeter, the opening being configured to receive a microarray slide and a spacer disposed about an inside perimeter of the opening;
• an optical window attached to the frame and disposed on one side of the opening;
• a fluid inlet port,
• a fluid outlet port;
• and
• a seal attached to the frame opposite the optical window,
• wherein the spacer is configured such that when the microarray slide is disposed within the opening, the microarray slide is spaced apart from the optical window, the space between the microarray slide and the optical window defining a chamber, and
• wherein the chamber is configured to receive a fluid through the inlet port, the fluid having a flow that is distributed across the microarray slide, and discharged from the microarray chamber through the outlet port.

An apparatus for conducting a melting curve analysis of nucleic acids on a microarray by exciting a predefined portion of the microarray with a light beam and detecting emissions of fluorescent light comprising:

• an illuminator assembly, including a light source configured to produce the light beam, the light beam comprising electromagnetic radiation having one or more wavelengths,
• an emissions detector configured to sense emissions of fluorescent light from the predefined portion of the microarray;
• a fluid circulation system, including
• a microarray cassette assembly defining a microarray chamber, the micro array cassette assembly including a fluid inlet port and a fluid outlet port,
• a pump configured to receive fluid from a fluid reservoir and to discharge the fluid through a fluid inlet line coupled to the fluid inlet port,
• a fluid outlet line coupled to the fluid outlet port, and
• a temperature control assembly including a temperature controller configured to regulate the temperature of a fluid within the fluid circulation system, and;
• a microarray positioner, including
• a microarray cassette support movably attached to a base and configured to receive the microarray cassette,
• a first support positioner attached to the base and configured to directionally move the microarray cassette support along a first axis, and
• a second support positioner attached to the base and configured to directionally move the microarray cassette support along a second axis, the second axis being perpendicular to the first axis.