The immunoassay of gibberellins : II. Quantitation of GA3, GA 4 and GA 7 by ultra-sensitive solid-phase enzyme immunoassays.

The development of sensitive and specific solid-phase enzyme immunoassays for gibberellic acid and gibberellins A4 and A7 is reported. The use of antisera of high apparent affinity (Ka over 10(10) l mol(-1)) in conjunction with alkaline phosphatase-labeled gibberellins allows, with minimum procedural effort, the quantitative determination of sub-picogram amounts of these gibberellins. The assays reported here are applicable to most gibberellins and can be set up with 1-1.5 mg of starting material. They represent the most sensitive methods for gibberellin determination known.