A modified quantitative determination of ampicillin in biological fluids.

immunofixation (2), and beta-mercaptoethanol reduction (3) of serum, with subsequent zone electrophoresis (Figure 1). In each instance, such reduction caused the band to disappear. The immunofixation and immunoelectrophresis procedures confirmed the presence of polymeric, polyclonal 1gM. One would expect that a discrete band would still be present on zone electrophoresis after reduction if 1gM were other than polyclonal and polymeric. This technique offers the advantage of savings in terms of expensive reagents and technologists’ time, and provides a rapid screen for polymeric 1gM.