Patent attributes
A bead dispenser device useful for supplying, one at a time, beads for heterogenous immunoassay, including an inner chamber having a return spring integrally formed to the inner chamber. The bead device also includes a plunger housed within a plunger chamber. The plunger includes a bead holding member and a notch. The return spring communicates with the notch of the plunger and biases the plunger in a resting position. In the resting position, the bead holding member is aligned with a bead receiving channel formed partly in the base of the inner chamber. When the plunger is depressed, the bead residing in the bead holding member is transported to a bead exit opening for dispensing therefrom. In this position, the return spring is also displaced inward to an inner portion of the inner chamber and is capable of agitating and contacting the beads located within the inner chamber. This ensures that the beads will not block or bridge the bead receiving channel which communicates with the bead holding chamber of the plunger.