There is disclosed a sample preparation chamber for a system for preparing samples of various compositions for assay by liquid chromatography. The sample preparation chamber is a container having a threaded cap and a threaded, lightweight, translucent plastic cup. A stirred/grinder shaft driven by a motor and connected to a propeller/grinder passes through the cap. The cap has a sloped bottom with a sump region, and a fill/empty pipe passes through the cap and has its outlet at or near the sump. A nozzle fill pipe arrangement allows the walls to be washed down as liquid is pumped into the cup. A second fill pipe with its outlet spaced up from the bottom of the cup is also used, and a sample metering valve having an inlet in said cup is present. The sample metering valve is used to isolate a known volume of the sample from the rest of the sample for release back into the cup after the remaining sample has been pumped to waste for purposes of diluting the known volume of sample to a known concentration.
An automated tablet dissolution apparatus adapted for use with tablet sinkers. In a preferred embodiment, the apparatus includes a dissolution vessel and an automated mechanism for agitating the contents of the dissolution vessel. The apparatus also includes an automated mechanism for measuring a desired volume of media, heating and degassing the volume and then dispensing the volume into the vessel, an automated mechanism for sampling the contents of the dissolution vessel, an automated mechanism for dispensing a tablet (and sinker, if desired) into the dissolution vessel, an automated mechanism for heating the dissolution vessel, and an automated mechanism for imaging the contents of the dissolution vessel. In addition, the apparatus includes an automated mechanism for emptying the contents of the dissolution vessel. According to one embodiment, such a vessel emptying mechanism includes (a) a waste media receptacle, the waste media receptacle having an inlet opening and defining a media chamber, (b) a first tube, the first tube having a first end and a second end, the first end being insertable into the dissolution vessel, (c) a second tube, the second tube having a first end and a second end, the first end of the second tube being connected to the second end of the first tube, (d) a sinker strainer disposed between the dissolution vessel and the waste media receptacle for straining a sinker from the fluid contents of a dissolution vessel, the sinker strainer having an inlet opening and an outlet opening, the second end of the second tube being connected to the inlet opening of the sinker strainer, (e) a third tube, the third tube having a first end and a second end, the first end of the third tube being connected to the outlet opening of the strainer, the second end of the third tube being connected to the inlet opening of the waste media receptacle, and an automated vacuum mechanism for drawing the contents of the dissolution vessel up through the first end of the first tube towards the media chamber of the waste media receptacle.
There is disclosed herein an automated sample preparation system for chemical assay of samples of materials. The sample preparation system includes a sample preparation chamber which includes a removable cup for taking to the location of solid or very viscous samples. The cup may be attached in sealing relationship to a cap through which extends various utilities such as a mixer/grinder to grind solid samples and mix non-homogeneous samples, a fill pipe to pump in liquid samples, an effluent pipe in the sump of the cup to allow pump of samples and solvents and a nozzle to allow liquids to be sprayed against the walls. A sample metering valve associated with the sample preparation chamber allows a known volume of sample to be isolated so that solvent may be pumped in to dilute the sample to a user defined concentration. A reversible pump is coupled by a pair of manifolds which are themselves coupled by solenoid operated valves to various sources of solvents, pressurized gas, vacuum, water, the sample preparation chamber and the assay system. A control system coordinates the operation of all remotely controllable units in the system to allow the user to customize various preparation processes.
An apparatus is proposed making it possible in automated manner to perform several analyses on the same sample. For this purpose several fixed, chemical preparation cells (10) can separately receive several fractions of the same sample. Reagent injection systems (24) associated with these cells, as well as stirrers (14) make it possible to prepare, in each of them, a chemical preparation which is transferred into an analysis cell (36) associated therewith by an air ejector (44). The same ejector discharges the preparation to the drain (38) when the analysis has been completed. Ducts (70, 72), as well as a discharge line (62) then make it possible to wash, rinse and empty each chemical preparation cell (10).
In a preferred embodiment, the apparatus includes a dissolution vessel removably seated within an aluminum platen. The apparatus also includes an assembly for automatically measuring a desired volume of media, heating and degassing the volume of media and then dispensing the volume of media into the dissolution vessel. In addition, the apparatus includes a carousel having a plurality of compartments, the carousel being rotatably mounted on a stage, the stage being alignable with the vessel. According to one mode of operation, an open-top, cage-type basket is placed in one or more compartments of the carousel, each basket containing a tablet intended for dissolution. The apparatus additionally includes a shaft aligned with the vessel, the bottom end of the shaft being adapted to frictionally fit together with a basket. The shaft is rotatable and vertically movable so that it can fit together with a basket, pick the basket up out of the carousel, lower the basket into the vessel, rotate the basket within the media and remove the basket from the media. The apparatus further includes a catheter automatically movable in and out of the vessel for sampling the media at desired times, an automated mechanism for loading and replacing a depth filter on the input end of the catheter, an automated mechanism for removing the basket from the end of the shaft after testing has been completed and an automated mechanism for removing media from the vessel after testing has been completed. The apparatus also includes a paddle shaft which may be used interchangeably with the basket shaft if tablets are placed directly in the compartments of the carousel and are then dispensed from the carousel into the vessel through an opening in the bottom of each carousel that is alignable with an opening in the stage.
A sample preparation method and apparatus is provided which is capable of automatic operation over a broad range with improved accuracy and precision, and which is capable of sampling with improved accuracy and flushing without operator intervention. A pair of syringes are used to measure large and small volumes of components, respectively, and can be operated automatically using a processor to prepare samples. Further, the method and apparatus incorporate a solvent selector valve which permits various solvents to be selected as required to prepare a particular sample. Automatic flushing of the apparatus is also provided after the preparation of each sample.
