Apparatus and method for mixing fluid or media by vibrating a pipette using nonconcentric masses

A mixing device for an immunochemistry system, the mixing device comprising:

• a stirrer configured to translate into a cuvette;
• a first nonconcentric mass configured to cause the stirrer to move in a first circular pattern;
• a second nonconcentric mass configured to cause the stirrer to move in a second circular pattern, the second circular pattern having a smaller radius than the first circular pattern;
• and
• a control unit configured to activate the first and second nonconcentric masses to cause the stirrer to move within the cuvette in the first circular pattern and the second circular pattern simultaneously.

A method of mixing paramagnetic particles within a cuvette, the method comprising:

• injecting paramagnetic particles from a pipette into a cuvette;
• applying a magnetic force outside of the cuvette to attract the paramagnetic particles to a wall of the cuvette;
• and
• moving the pipette within the cuvette in a first circular pattern and a second circular pattern simultaneously, the second circular pattern having a larger radius than the first circular pattern.