[Materials for performing external quality control of the measurement of ceruloplasmin activity].

Quaternary monophosphonium compound 1-triphenyl phosphoniomethyl naphthalene bromide stabilizes blood serum samples and preserves the activity of ceruloplasmin (CP 1.16.3.1) intact for 30 days. For preparing the reference material, 10 ml of serum is added to 190 ml of 1.55 mM solution of this compound, left for 24 h at 4-8 degrees C, poured in small flasks, stored at the same temperature, and used as reference material as needed for checking up the correctness of ceruloplasmin measurements in biochemical laboratories.