Improved bioassay for insulin by continuous glucose monitoring

The USP bioassay for insulin currently used by industry and government requires a sc injection of insulin to rabbits and multiple assays of blood glucose. One hundred and forty-four rabbits are usually assayed, each assay taking at least 2 weeks. A bioassay for insulin is described. The new assay is based on a continuous monitoring of blood glucose and repeated iv injection of insulin to dogs. The test is completed in 1 day and is carried out on one dog. The interassay variability of seven repeated tests of an off the shelf soluble insulin was +/- 8%.