Patent ID: 7704457
Filing Date: 2010-04-27
Classification: B01F,B01L,G01N,Y10T

Abstract:
1. An automated analyzer for discrete sample aliquots with carrier fluid recycle comprising: (a) an analytical conduit containing hydrophobic carrier fluid, the conduit and hydrophobic carrier fluid receiving discrete liquid aliquots of predetermined volume which are immiscible with the hydrophobic carrier fluid, such that the discrete aliquots are disposed in the carrier fluid and movable concurrently therewith; (b) a selection/recycle valve; (c) a hydrophobic carrier fluid recycle reservoir connected to the selection/recycle valve (d) a bidirectional pump connected through the selection/recycle valve to a first location along the analytical conduit, communicating with the hydrophobic carrier fluid and being operable to induce controlled bidirectional flow of the carrier fluid within the analytical conduit in response to a first control signal; the selection/recycle valve alternatively connecting the bidirectional pump with either the analytical conduit or the hydrophobic carrier fluid recycle reservoir such that it is operable to direct the flow of hydrophobic carrier fluid into or out of the pump to or from the analytical conduit or such that it is operable to direct the flow of hydrophobic carrier fluid into or out of the pump to or from the hydrophobic carrier fluid recycle reservoir from which the analytical conduit is replenished with recycled hydrophobic carrier fluid; (e) a shut-off valve located at a second location along the analytical conduit, communicating with the hydrophobic carrier fluid and being operable to prevent flow of the carrier fluid at said second location of the analytical conduit in response to a second control signal; (f) a sampling unit communicating with the analytical conduit located between the bidirectional pump and the shut-off valve for providing discrete liquid aliquots to the analytical conduit; (g) a dosing unit located at a third location along the analytical conduit, the third location being intermediate said first location of the pump and the second location of the shut-off valve, and the dosing unit having a reagent feed valve connected to a reagent containing reservoir, the reagent feed valve being disposed between the reagent containing reservoir and the analytical conduit such that the reagent containing reservoir communicates with the analytical conduit through the reagent feed valve to supply fluid from the reagent-containing reservoir to discrete liquid aliquots disposed in the analytical conduit, wherein the reagent feed valve is responsive to a third control signal; (h) a controller providing the first, second and third control signals respectively to the pump, the shut-off valve, and the feed valve of the dosing unit, whereby the controller, pump, shut-off valve and carrier fluid are operable to position discrete liquid aliquots at predetermined locations along the analytical conduit, and whereby the pump may be used to draw fluid from the reagent containing reservoir of the dosing unit and supply it to the discrete liquid aliquots upon concerted operation of the pump, shut-off valve, and feed valve; and (i) a detector located at a fourth position with respect to the analytical conduit and operable to detect an analyte in a discrete liquid aliquot positioned at the fourth position.