A small-scale version of line immunoelectrophoresis in combination with immunoprecipitate excision is described as a rapid and convenient technique to purify proteins on a micro scale in biogenesis studies. In the purification and to result in a higher state of purity than an isolation procedure using protein A-Sepharose. Since the method furthermore allows a simultaneous purification of several different protein antigens from the same sample, it may be of interest as an alternative method to other procedures in the purification of proteins on a micro scale.