A comparative study of micro-ammonia determinations in plasma using two different methods

Two commercially available kits for determining blood ammonia were compared, an enzymatic method requiring a sample volume of 100μl and a nonenzymatic method requiring 1 ml of sample. Calibration curves for both kits were linear to 270 μmol/l, however correlation studies on plasma samples revealed a lack of agreement between methods (r = 0.825, Y = 0.76X + 51). Improved correlation occurs when portein interference is eliminated from the enzymatic procedure. Finally, the nonenzymatic method is modified to accommodate 100 μl of sample and compared to the original method.