Microtransferrinuria and microalbuminuria: enhanced immunoassay.
An enhanced-sensitivity immunoassay for urinary microtransferrin and microalbumin was devised based on protein precipitation with cold trichloroacetic acid followed by dissolution of the precipitate in a small volume of phosphate buffer. Samples can be concentrated 10-fold by this method while at the same time removing many of the chromogens present in urine. Concentrated samples were assayed by immunoturbidity and radial immunodiffusion. The average recovery for urinary microtransferrin was 82 percent and for microalbumin 91 percent. The reference range for 80 normal adults for microtransferrinuria and microalbuminuria is 0 to 0.9 and 5 to 32 mg per g creatinine, respectively. The same method can be used for the assay of other proteins such as B2-microglobulin in the urine or the cerebrospinal fluid.
McCormick
C P
CP
Department of Pathology, Wake Forest University, Winston-Salem, NC 27103.
Shihabi
Z K
ZK
Konen
J C
JC
D000143:Acids / Q000494:pharmacology; D000419:Albuminuria / Q000652:urine*; D006801:Humans; D007118:Immunoassay / Q000379:methods*; D005779:Immunodiffusion; D007158:Immunologic Techniques; D009391:Nephelometry and Turbidimetry; D009994:Osmolar Concentration; D012016:Reference Values; D014168:Transferrin / Q000652:urine*
D000143:Acids; D014168:Transferrin