Determinations of immunoglobulins G, A, and M in the Technicon RA-1000

Abstract

We evaluated the Technicon RA-1000 "Random Access" analyzer for the measurements of immunoglobulins G, A, and M in serum by turbidimetry. For various concentrations of serum pools the total CV ranged from 3.0 to 4.5% for IgG, from 3.1 to 3.2% for IgA, and from 4.8 to 5.4% for IgM. The linearity of the standard curves was good in the clinically useful ranges. Results for patients' samples correlated well with those determined with the Beckman Auto ICS (rate nephelometric method). Normal reference intervals (based on data for 200 healthy blood donors) are 7.67 to 16.87 g/L for IgG, 0.87 to 3.89 g/L for IgA, and 0.61 to 2.70 g/L for IgM. The RA-1000 requires only 8 microL for all three tests and can analyze 25 specimens for all three proteins in 37 min. Compared with other methods for immunoglobulin assays, the RA-1000 has higher throughput and offers significant savings in labor and reagent costs.