A rapid procedure for crossed radio immunoelectrophoresis

A procedure for performing crossed radio immunoelectrophoresis (CRIE) with significantly reduced exposure times has been developed. The rapid method has been effected by using a highly sensitive X-ray film (Du Pont Cronex-4) and X-ray intensifying screen (Du Pont Lighting Plus) and by exposing at low temperatures (-70 degrees C) in a Kodak X-Omatic cassette. Exposure at -70 degrees C appears to be critical to obtain optimal radiostaining. Furthermore, the isotope concentration has been increased from 250,000 to 500,000 cpm without any loss of specificity or reproducibility. The rapid CRIE procedure makes it possible to obtain a CRIE screening within 1 day and, furthermore, a complete CRIE classification (CRIE classes A-G) within 5 days.