Share Email Print

Proceedings Paper

Error-budget considerations in diagnostic instrumentation
Author(s): G. E. Cohn
Format Member Price Non-Member Price
PDF $14.40 $18.00
cover GOOD NEWS! Your organization subscribes to the SPIE Digital Library. You may be able to download this paper for free. Check Access

Paper Abstract

Analytical instrument systems present assemblies of components which each introduces its won contribution to the overall system precision. Combining realistic models of detector response with a Beer's Law model for absorbance (A) provides a prediction for the overall system uncertainty. For the constant detector uncertainty model, reasonable values of sample parameters lead to substantial increases in the absorbance at minimum relative concentration error (RCE), the value of the RCE and the limits of the range of A values for best RCE. Similar effects follow from the square root detector model. In both detector models these effects are increased by concentration uncertainty. Assay chemistry factors dominate the system RCE at low A, making high precision difficult at low A. For fluorescence measurements, since analyte concentration is nearly proportional to detected signal, the same detector models indicate no minimum in RCE.

Paper Details

Date Published: 22 May 1997
PDF: 13 pages
Proc. SPIE 2985, Ultrasensitive Biochemical Diagnostics II, (22 May 1997); doi: 10.1117/12.274355
Show Author Affiliations
G. E. Cohn, Cyber Tech Applied Science, Inc. (United States)

Published in SPIE Proceedings Vol. 2985:
Ultrasensitive Biochemical Diagnostics II
Gerald E. Cohn; Gerald E. Cohn; Steven A. Soper, Editor(s)

© SPIE. Terms of Use
Back to Top