Apparatus and method for handling fluids for analysis
A reaction vessel with a bottom drain opening supporting a selected unpressured head of fluid by the surface tension of the fluid. A device processing zone includes a support for spaced rows of reaction vessels, passages communicating with their drain openings of supported vessels, and a pressure source for selectively draining fluid through the drain openings. Generally horizontal bar magnets are supported for selected vertical movement between the vessel rows. A dispensing head has X discharge openings selectively positionable over X selected reaction vessels. A metering pump mechanism selectively meters X a selected quantity of fluid a bulk supply (where X is at least four), and selectively pumps the metered selected quantities through the drain openings to the selected reaction vessels. Methods of drawing fluid from the vessels using the pressure source, and moving the magnets to form a pellet of analyte are also included.
1. A reaction vessel for testing an analyte in a fluid, comprising a vessel having an open top and a drain opening in its bottom, said drain opening being adapted to support a selected height of fluid and to drain fluid therethrough when a selected pressure differential exists between the top of the fluid and the bottom of the vessel, further comprising a non-wettable coating around the drain opening on the outer surface of the vessel.
2. The reaction vessel of claim 1 , further comprising a drain opening protrusion extending beyond the bottom of the vessel.