Automated serum albumin determination by use of the immediate reaction with bromcresol green reagent.

It has been demonstrated recently that the reaction of serum samples with bromcresol green reagent proceeds in two steps, albumin being responsible for the immediate reaction and other serum proteins for the slower one. I show here that the immediate reaction, used for albumin determination, can be automated. Two different automated systems are described: the LKB 2086 Reaction Rate Analyzer and the multichannel analysis system LKB 2480 Prisma. With the first system, 60 (or 120) samples per hour were run with a within-day standard deviation of 0.3 g/liter; with the second system, a feed rate of 150 samples per hour was used (SD, 0.3 g/liter, within-day). Comparison with other methods gave the following equations: y (LKB 2086) = 1.44 + 0.97 X (immunodifussion) (n = 43; r = 0.98) and y(Prisma) = 2.04 + 0.96x (manual method) (n = 73; r = 0.98). Thus albumin determinations can be done reliably, quickly, and simply at low reagent and labor cost.