Abstract: Disclosed herein is an anti-rotational apparatus for ensuring secure placement of a sample tube on a sample carousel. The sample tube includes a first open proximal end and a second closed distal end. Between the ends and located adjacent to the proximal end, the sample tube includes a radially outwardly extending annulus having an abutment surface. The abutment surface includes anti-rotational structure. The invention in an exemplary embodiment includes a sample carousel having an outer periphery zone having a plurality of openings. The openings are sized and shaped for compatible sliding engagement with the sample tube and adjacent to the openings are abutment surfaces. Each abutment surface includes anti-rotational structure and the anti-rotational structure is sized and shaped for compatible mating engagement with the sample tube anti-rotation structure.

Abstract: Disclosed herein is an anti-rotational apparatus for ensuring secure placement of a sample tube on a sample carousel. The sample tube includes a first open proximal end and a second closed distal end. Between the ends and located adjacent to the proximal end, the sample tube includes a radially outwardly extending annulus having an abutment surface. The abutment surface includes anti-rotational structure. The invention in an exemplary embodiment includes a sample carousel having an outer periphery zone having a plurality of openings. The openings are sized and shaped for compatible sliding engagement with the sample tube and adjacent to the openings are abutment surfaces. Each abutment surface includes anti-rotational structure and the anti-rotational structure is sized and shaped for compatible mating engagement with the sample tube anti-rotation structure.

Abstract: Disclosed herein is a diagnostic instrument for analyzing liquid samples. The diagnostic instrument in accordance with this invention includes a sample carousel and a diagnostic carousel. The sample carousel includes at least one sample tube and in the exemplary embodiment a plurality of sample tubes, each having unique identifying indicia readable by a machine reader. The sample tube capable of storing the liquid sample to be analyzed. The diagnostic carousel including at least one pipette capable of storing liquid sample to be analyzed. There are matching number of pipettes to sample tubes and each having matching unique identifying indicia which is matched with the appropriate sample tube. The diagnostic carousel being offset from the sample carousel and lying in a different plane from the sample carousel. Each pipette including a transfer mechanism for transferring sample from the sample tube directly to the pipette.

Abstract: Disclosed herein is a diagnostic vessel known as a pipette. The pipette includes a main pipette housing having a hollow interior defining a first chamber and a proximal end and an open distal end. The pipette includes a pipette tip assembly connectable to the main pipette housing having a hollow interior defining a second chamber, the pipette tip hollow interior having open proximal and distal ends and the first and second chambers in fluid communication. The pipette tip includes a plunger within the second chamber. Additionally, the pipette tip assembly includes structure for normally urging the plunger to a first position such that the plunger closes the distal end of the pipette tip. The structure for normally urging the plunger to a first position also allows the plunger to be urged to a second position, wherein the plunger opens the distal end and allows fluid communication from the distal end of the pipette tip through the second chamber and into the first chamber.