Detection of aggregate formation during production of human immunoglobulin G by means of light scattering.

In human immunoglobulin preparations with a concentration of 50 mg/ml aggregate formation below 0.3% is difficult to quantify. Such small traces may later be responsible for reduced stability and therefore this generation during the process must be prevented. The influence of process conditions on the conformational changes and subsequent aggregation of immunoglobulins were assessed by size-exclusion chromatography (SEC), UV and static light scattering (LS) detection. This work focused on pH-adjustment experiments since several pH adjustments are required during the production of intravenous immunoglobulin G. Experiments in a labscale were made varying process conditions in a narrow range. It was possible to detect differences concerning the formation of aggregates dependent on these small variations of process conditions.