Barnett M D, Brozović B
Clin Chim Acta. 1975 Feb 8;58(3):295-8. doi: 10.1016/0009-8981(75)90450-7.
An automated micromethod for measuring copper concentration in 0.2 ml of serum employing formaldehyde-oxalydihydrazide as chromogen and using an Auto-Analyzer (Technicon) is presented. The use of formaldehyde-oxalyldihydrazide resulted in a stable and noise-free baseline. The coefficient of variation of the micromethod was 2.4%. The recovery of copper added to samples was 102%. A good correlation between the serum values estimated by the described method and the manual method of Summers (1) (r = 0.929; P less than 0.001) was found when copper standards were prepared in 0.277 M glucose. The mean serum copper concentration found in 26 healthy adult males is 94.1 mug/dl (range: 80 to 120 mug/dl) and in 20 females is 109.8 mug/dl (range: 71 to 170 mug/dl), the difference being statistically significnt (P less than 0.02).