Determination of several markers of diabetic nephropathy in human urine with capillary electrophoresis

In this work, a new high performance capillary electrophoresis assay for creatine (Cr), creatinine (Cn), urea (U), uric acid (Ua), markers of human diabetic nephropathy, in urine with UV detection at 200 nm was developed. The urine sample was diluted by 2 times before using. The optimum separation was performed in a 50 mmol·L-1 acetic acid buffer (pH 4.0) using a fused-silica capillary (21 cm×75 μm) at 25 ℃ with the electric field of 571 V/cm and the separation time of about 13 min. The detection limit (S/N=3) was 5, 0.8, 100, 5 μmol/L, and the linear ranges were determined to be 10～1000 μmol/L, 5～3000 μmol/L, 1000～30000 μmol/L, 10～1500 μmol/L for Cr, Cn, U, Ua, respectively. 