Simple Adaptation of the Technicon SMAC System to Operate 18 Channels with Reduced Volumes of Plasma

The Technicon SMAC system was adapted to function with much smaller volumes of plasma than those used in standard procedures. With only minimal operator-entered changes to the 7·6 computer program, and simple modifications of the glucose and alkaline phosphatase channels, the SMAC analyser performed equally well when the plasma volume was decreased from 235 μl sequentially down through 176 μl, 142 μl, and 105 μl. The basic principle employed was to maintain a constant flow rate of diluted sample plus diluent with decreasing sample size. The instrument proved to have the capability of operating successfully on all channels with lower signals than those encountered with the unmodified system.