Development of an improved time-resolved fluoroimmunoassay for simultaneous quantification of C-peptide and insulin in human serum.

OBJECTIVES

Diabetes mellitus is a chronic disease affecting millions of people globally and resulting in significant death rates each year. A fast, inexpensive alternative to traditional testing and monitoring techniques is desirable, since secretion of insulin and C-peptide is impaired in diabetes mellitus.

DESIGN AND METHODS

A highly sensitive immunoassay was developed for the simultaneous measurement of C-peptide and insulin levels in human serum, utilizing dual-label time-resolved fluoroimmunoassay (TRFIA) and magnetic particle technologies. This assay was characteristic for a single-step sandwich-type immunoassay, wherein antibody-coated magnetic particles were used as the solid phase and Eu(3+) and Sm(3+) chelate labels were used for detection.

RESULTS

Antibody-coated magnetic particles in a TRFIA format performed well in addressing a number of quantitative needs.

CONCLUSIONS

The results of this assay correlated well with commercial chemiluminescence assays and provided a number a advantages, including reduced sample volume, reduced reagent and personnel costs and reduced assay time, while maintaining the required clinical sensitivity.