LONG-TERM STABILITY OF ALBUMIN, PROTEIN HC, IMMUNOGLOBULIN-G, KAPPA-CHAIN-IMMUNOREACTIVITY AND LAMBDA-CHAIN-IMMUNOREACTIVITY, OROSOMUCOID AND ALPHA(1)-ANTITRYPSIN IN URINE STORED AT -20-DEGREES-C

The stability of albumin, protein HC, immunoglobulin G, kappa- and lam bda-chain immunoreactivity, orosomucoid and alpha(1)-antitrypsin in ur ine stored at -20 degrees C for up to 24 months was investigated. Sign ificant decreases of the median concentration values for protein HC, I gG and alpha(1)-antitrypsin were observed for native urine. Addition t o urine of a preservative solution containing benzamidinium chloride, EDTA, tris(hydroxymethyl)-aminomethane and azide prevented the decreas es of the concentration values for protein HC and IgG but not for alph a(1)-antitrypsin. The median concentration values for albumin, orosomu coid and kappa- and lambda-chain immunoreactivity did not change signi ficantly upon storage of native urine, nor for urine with the preserva tive solution.