Measurement of soluble transferrin receptor by immunoturbidimetry and immunonephelometry

Objective: To evaluate and compare two new commercially available immunotur bidimetric and immunonephelometric assays for measuring soluble transferrin receptor (sTfR) in serum. To adapt the immunonephelometric assay to an aut omated chemistry analyzer. Design and methods: Total imprecisions and detection limits were calculated and compared. Fifty-six samples were used for methods comparison. The neph elometric assay was adapted to the Hitachi 911 analyzer. Results: Both methods displayed acceptable imprecisions and detection limit s. Their correlation was good but a proportional bias was observed. The ada ptation of the nephelometric assay to the Hitachi 911 was successful. Conclusions: These two new immunoassays are analytically acceptable and mor e practicable than previously developed methods. The differences observed b etween both methods underscores the need for standardization, The nephelome tric assay was easily adaptable to an automated chemistry analyzer. Copyrig ht (C) 2000 The Canadian Society of Clinical Chemists.