A unique clinical chemistry analyser is described which processes 90 μl of whole blood (fingerstick or venous) into multiple aliquots of diluted plasma and reports the results of 12 tests in 14 min. To perform a panel of tests, the operator applies the unmetered sample directly into a single use, 8 cm diameter plastic rotor which contains the required liquid diluent and dry reagents. Using centrifugal and capillary forces, the rotor meters the required amount of blood, separates the red cells, meters the plasma, meters the diluent, mixes the fluids, distributes the fluid to the reaction cuvettes and mixes the reagents and the diluted plasma in the cuvettes. The instrument monitors the reagent reactions simultaneously using nine wavelengths, calculates the results from the absorbance data, and reports the results.

We describe a portable clinical chemistry analyzer for point-of-care measurements of multiple analytes in less than 10 min from approximately 40 microL of whole blood (fingerstick or venous). Whole blood is applied directly to a 7.9-cm-diameter, single-use plastic rotor containing liquid diluent and greater than or equal to 4-12 tests in the form of 1- to 2-mm-diameter dry reagent beads. The reagent/rotor is immediately placed in a portable instrument along with a ticket/label results card. As the instrument spins the rotor, capillary and rotational forces process the blood into diluted plasma, distribute the patient's diluted sample to cuvettes containing the reagent beads, and mix the diluted sample with the reagents. The instrument monitors the chemical reactions optically at nine wavelengths; sample volume and temperature are also measured optically. The calibration data for each reagent are read from a bar code on the periphery of each rotor. The instrument processes all the measurements to calculate, store, print, and communicate the results. Each reagent/rotor contains an enzymatic control that must be within a defined range before the results from that analysis are reported.

We describe an immunoassay system suited to patient-side assay of therapeutic drugs and blood proteins. The system consists of an electronic monitor and single-use plastic cartridges containing dry reagents and liquid diluents. The monitor is turned on by insertion of a cartridge. To run the test, the user applies an unmeasured drop of blood to the cartridge when prompted by the monitor. All subsequent steps are performed without further user intervention and results are provided in less than 3 min. The system hemolyzes and precisely dilutes the blood. Hemoglobin concentration is measured, then the diluted blood is precisely diluted further and mixed with two dry reagents. The drug concentration is measured by a turbidimetric latex agglutination inhibition reaction. Theophylline and hemoglobin assay results for clinical samples correlate well with results of widely used comparison methods.