A noninstrumented quantitative test system and its application for determining cholesterol concentration in whole blood

Abstract

A novel noninstrumented technology has been developed for quantifying analytes of clinical interest in biological fluids. Application of this technology is exemplified by the development of a quantitative cholesterol test with performance equivalent to state-of-the-art instrumented methods. The assay chemistry combines two separate processes located in different areas of a test strip: enzymatic action on serum cholesterol to produce hydrogen peroxide (5 × 10 mm enzyme reagent pad) and quantification of the hydrogen peroxide (5 × 70 mm measurement region). Color bands are formed in the measurement area through the use of a redox-coupled indicator system. The height of the color band on the strip is directly proportional to the sample cholesterol concentration. A one-step cassette contains all components necessary to run the test and includes blood filtration and automatic sample measurement, so that unmeasured fingerstick whole-blood specimens can be analyzed by the nontechnically trained user. The test is complete in <15 min, is read visually like a thermometer, and gives results that are in excellent correlation with established instrumented methods.