Evaluation of the effect of two gadolinium-containing contrast-enhancing agents, gadobutrol and gadoxetate disodium, on colorimetric calcium determinations in serum and plasma.

OBJECTIVE

To determine the extent to which the gadolinium-containing contrast agents, gadobutrol (Gadovist) and gadoxetate disodium (Primovist/Eovist), interfere with the colorimetric measurement of calcium concentrations in serum and plasma.

MATERIALS AND METHODS

Gadobutrol and gadoxetate disodium were added in various concentrations to serum and plasma from healthy volunteers; the calcium concentration in these samples was then measured by standard colorimetry methods and atomic absorption.

RESULTS

At clinically relevant concentrations, neither gadobutrol nor gadoxetate disodium influenced the results of the calcium measurement in serum or plasma. Only at the highest concentrations tested (50 mM gadobutrol; 25 mM gadoxetate disodium), an effect was seen in some cases. Results were confirmed by atomic absorption spectroscopy as the reference method.

CONCLUSIONS

At clinically relevant concentrations, gadobutrol and gadoxetate disodium did not interfere with standard colorimetric methods for calcium determination.