THE DETERMINATION OF ALPHA(1)-MICROGLOBULIN BY MEANS OF AN AUTOMATED LATEX IMMUNOASSAY

Polystyrene (latex) particles coated with human anti-alpha(1)-microglo bulin antibodies are used in an automated ''kinetic'' assay for alpha( 1)-microglobulin in urine. For values below 12 mg/l, there was no sign ificant difference between two kinds of standard, but above 12 mg/l th e results depend on the origin of the alpha(1)-microglobulin standard. Correlation between values obtained with both standards was good (r(2 ) = 0.968). The method has a between-run imprecision (CV) of 11-16%. C omparison with two commercial enzyme immunoassays gave a bias of -10% to +40%, while two nephelometric methods differed by 0% to 23%, possib ly because the standards used in these methods were of different origi n. These results indicate the necessity of standardization of the dete rmination of alpha(1)-microglobulin. The detection limit of our method was 0.8 mg/l, enabling the application of the method for epidemiologi cal investigations.