Abstract: A colorimetric urea determination method, reagent, and reagent kit useful in end point and kinetic urea determination is disclosed. Urea in a liquid sample reacts with o-phthalaldehyde and a chromogenic compound in the presence of a linear long hydrocarbon chain amidobetaine to produce an intensely colored reaction product, the concentration of which is linearly related to the urea concentration in the sample.

Abstract: A control material for use in the determination of glycosylated and total hemoglobin, and a method of preparing the same, are disclosed. The control is prepared by the steps of hemolyzing red blood cells, preferably in the presence of a detergent, followed by removal of stroma and lipids from the hemoglobin with an organic solvent such as toluene in the presence of a polyhydroxy compound such as sucrose. A hemoglobin-rich fraction is separated from the resulting mixture and dialyzed against a solution of a polyhydroxy compound. The dialysate may be lyophilized to provide a stable, dry product suitable for reconstitution.

Abstract: A collapsible fluid collection device is provided which includes a container having upper and lower relatively movable telescopically disposed members, and sealing means for the container sealing the container against ambient air flowing between the members and into the container.

Abstract: An intravenous catheter placement device is provided which includes a catheter having a hub and a cannula. A winged stabilizing member is slideable onto the catheter hub. The catheter hub and stabilizer have cooperating keys and keyways to provide predetermined positioning of the stabilizer on the catheter. A needle introducer having a hub and a needle is provided with a cantilever in fixed relation with the needle bevel. The cantilever is located between the luer lock ears on the catheter hub when the introducer is inserted into the catheter to provide a predetermined orientation between the needle bevel and the wings of the stabilizer.

Abstract: An endometrial sampler is provided for obtaining an endometrial sample for clinical analysis which is safe to use and reduces patient discomfort. The sampler includes a handle and a flexible plastic probe having grooves on diametrically opposite sides adjacent the distal end of the probe. Each groove has a pair of sharp edges with each edge formed at the intersection of the periphery of the probe and a sidewall of the groove with the two forming an acute angle at their intersection. The probe is of solid plastic, relatively small in diameter and can be bent before insertion into the uterus of a patient to reduce patient discomfort.

Abstract: A mixing system and method for analyzing a specimen is provided which includes introducing a predetermined number of discrete jets of liquid reagent into a container carrying a specimen. The jets of reagent cause turbulent mixing of the reagent and specimen. The jets are time-spaced to allow settling of the mixture between jets to prevent the escape of the mixture from the container. After the reagent and specimen are thoroughly mixed, a characteristic of the mixture is then detected.

Abstract: A blood collection device for collecting and separating whole blood into its relatively low and high density phases includes a collection container, and a housing having an enlongate passageway in the housing. Gel-like material having a specific gravity intermediate the specific gravities of the separated high and low density phases is disposed in the passageway. A piston having a specific gravity greater than that of the gel-like material is disposed in the passageway and sized to allow gel-like material to flow past it at a low flow rate and to retard the movement of the piston during centrifugation of the device. Means for preventing the flow of the gel-like material from the housing and toward the interface of the phases until the piston has moved out of the passageway is provided.

Abstract: A disposable tip and piston assembly for a pipettor mechanism includes a hollow tip member adapted to be detachably connected on the distal end of the pipettor mechanism, and a piston member slidably disposed within the tip. The pipettor mechanism includes a plunger rod adapted to detachably engage the piston, and an ejector mechanism which permits rapid removal of the tip and piston assembly without the user contacting the assembly. The piston member is adapted to directly contact the substance being pipetted, for high accuracy in pipetting. The ejector mechanism and the detachable connection of the tip and piston assembly to the pipettor mechanism insulates the pipettor mechanism and its operator from contamination by the substance being pipetted.

Abstract: A patient breathing apparatus is disclosed which includes a liquid drain connected to receive liquid condensation. The drain includes a barrier which is water permeable and gas impermeable when wet. The barrier may be provided with a water soluble layer that is gas impermeable when dry.