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PubMed · 2302774

Calibration in three dimensions: optimizing a two-parameter calibration technique to extend the range of an immunoturbidimetric urinary albumin assay into antigen excess.

C Tillyer
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Abstract

I describe a general technique, called "two-parameter calibration," which allows precise determination of analyte from non-monotonic calibration plots and the calibration of immunoturbidimetric assays in antigen excess. Using three-dimensional calibration plots and relative-sensitivity curves, two optimal parameters may be selected from a number of possible options by using criteria presented here. Choosing two different values of delta At1-t2, the change in absorbance from time t1 to t2--as the reaction parameters in an immunoturbidimetric assay for albumin, I have optimized the choice of time interval for two-parameter calibration and extended the working range of the assay by three- to fourfold. The albumin assay shows excellent agreement of observed and expected values (r = 0.996) and also with results of a routine kinetic dye-binding method used on diluted plasma samples (r = 0.970).

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AlbuminsAlbuminuriaAutoanalysisCentrifugationHumansImmunoassayNephelometry and TurbidimetryReproducibility of ResultsSerum AlbuminStatistics as TopicJournal Article

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C Tillyer. 1990. Calibration in three dimensions: optimizing a two-parameter calibration technique to extend the range of an immunoturbidimetric urinary albumin assay into antigen excess.. https://pubmed.ncbi.nlm.nih.gov/2302774/

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