Discrete automated chemistry system with tableted reagents

An instrument/reagent system with tableted reagents has been developed for performing ultraviolet/visible photometric assays. Preformed disposable plastic cuvettes pass through a stationary track every 5 s, providing a maximum throughput of 698 tests/h. The photometric system consists of a single light source with a separate set of light guides for each of eight photometer stations; bichromatic readings are possible at any of seven wavelengths between 340 and 630 nm. Tablets for 30 different analytes have been developed, each of which contains all necessary components for a single determination. Tablets are dispensed from disposable dispensers into cuvettes under the direction of the system's microprocessor and are completely dissolved within 45 s by ultrasonic agitation. Sample volumes range from 2 to 20 microL. Test requests are selected on a cathode-ray tube display, and sample-container bar-code labels are automatically printed. Sample entry is totally random. The system is designed to provide reagent quality control and also serum and reagent blank corrections for each test. Examples of equilibrium, zero-order, and first-order kinetic assays are presented.