Apparatus for automatic sampling of biological species employing disk microfluidics system

A method for operating a field portable diagnostic apparatus having a microfluidic circuit defined in a rotatable disk with a center comprising:

• disposing a sample having at least one analyte therein into a sample reservoir defined in the rotatable disk;
• disposing the rotatable disk into a reader;
• spinning the rotatable disk in the reader at a separation rate for a separation time to separate the sample into a plurality of separated components;
• mixing functionalized magnetic nanoparticles with at least one of the plurality of separated components in a mixing chamber by spinning the rotatable disk using selectively reversed or oscillating cycles of rotation;
• moving at least one of the plurality of separated components into at least one detection chamber by spinning the rotatable disk, the at least one detection chamber comprising a sheer horizontal surface acoustic wave (SH-SAW) biosensor;
• and
• measuring the at least one analyte in the at least one detection chamber comprising the SH-SAW biosensor,
• where mixing functionalized magnetic nanoparticles with at least one of the plurality of separated component in a mixing chamber by spinning the rotatable disk comprises oscillating the rotatable disk at an oscillation angle of at least 180 degrees.