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37.2.2. Freelite and Hevylite Precision on the Optilite

Chapter 37

37.2.2. Freelite and Hevylite Precision on the Optilite

Precision on the Optilite is very good due to the use of disposable cuvettes and stringent washing protocols for the sample probe, reagent probe and mixing paddle. During Freelite assay validation, assay precision was assessed using 3 control fluids that ranged in concentration from 4.7 mg/L to 71.8 mg/L. The maximum intra- and inter-assay imprecision for κor λ Freelite assays was 3.3% and 3.2%, respectively. Similar studies of Hevylite reagents utilising control fluids that varied from 0.26 g/L IgAκ to 25.18 g/L IgGκ demonstrated a maximum intra- and inter-assay imprecision for 6 Hevylite assays of 3.2% and 4.7%, respectively[891][1145][894].

Thouless et al.[1144] reported excellent inter-assay precision for Freelite Optilite assays under routine simulated conditions, with a maximum imprecision of 7.0%. This was supported by Leung et al.[1146] who reported CVs of <8% at every level for multiple serum assays (including Freelite) run on the Optilite in routine practice. A number of studies have reported very good Hevylite Optilite assay precision[891][894][892][893] with typical CVs of 3-8%.

Jamil et al.[1160] assessed the performance of the Freelite Mx kits for CSF analysis (Chapter 36) and reported that the assays were linear, with acceptable CVs, and produced results that compared well to those generated by the predicate method.

References

    • 1. Kerr J, Ahaliwal S, Kausar S, Murphy F, Harding S. Evaluation of serum IgM Hevylite assays; IgM kappa and IgM lambda for use on the Binding Site Optilite analyser. Clinical Chemistry 2015;61:A201a
    • 2. Kerr J, Dhaliwal S, Kausar S, Murphy F, McEntee D, Harding S. Performance of serum IgM Hevylite assays; IgM kappa and IgM lambda for use on the binding site Optilite analyser. Clinical Chemistry and Laboratory Medicine 2015;53:T280a
    • 3. Southan L, Brown A, Coley M, Kaur A, McEntee D, Harding S, Showell P. Performance of Hevylite IgA kappa and IgA lambda assays for use on the Binding Site Optilite protein analyser. Clinical Chemistry and Laboratory Medicine 2015;53:T279a
    • 4. Southan L, Brown A, Coley M, Kaur A, Showell P. Performance of serum IgA kappa and IgA lambda assays for use on the Binding Site Optilite protein analyser. Clinical Chemistry 2015;61:A187a
    • 5. Thouless S, Overton J, Kenny P, Harding S. Evaluation of the analytical performance of multiple Optilite systems under routine conditions. Clinical Chemistry 2015;61:A240a
    • 6. McEntee D, Assi M, Murphy F, Kausar S, Mavi N, Bell I, et al. Evaluation of the serum IgG Hevylite Kappa and IgG Hevylite Lambda immunoassay on the Optilite® turbidimetric analyser. Presented at AACC 2016
    • 7. Leung F, Spencer M, Blasutig IM. Evaluation of free light chains and various protein assays on the Optilite® turbidimetric analyser. Presented at AACC 2017:B-357a
    • 8. Jamil O, McEntee DG, McCusker M, Matters DJ. Evaluation of the Freelite Mx™ kappa free and lambda free assays on The Binding Site Optilite® turbidimetric analyser using CSF samples. Presented at AACC 2018:B-479a