Enzyme immunoassay of pancreatic glucagon at the picogram level using beta-D-galactosidase as a label.
An enzyme immunoassay of pancreatic glucagon was established by using E. coli beta-D-galactosidease [EC 3.2.1.23] as a marker. In order to increase the sensitivity of the immunoassay, different peptides obtained from glucagon fragments were used to produce the enzyme conjugate and the immunogen. Antiserum N6E raised against C-terminal fragment peptide (15-29) could be diluted to more than 1 : 100,000 in the assay and was highly specific for pancreatic glucagon. The antiserum reacted well with the C-terminal fragment peptide (21-29) as well as another fragment peptide (15-29) and pancreatic glucagon. The enzyme immunoassay using antiserum N6E and fragment peptide (21-29)-enzyme conjugate could detect as little as 1 to 2 pg of glucagon. The mean recovery of glucagon added to serum specimens was 104% and the coefficients of variation were 3.7-14.5% (within assay) and 9.0-18.5% (between assay).
D004926:Escherichia coli / Q000201:enzymology; D005696:Galactosidases; D005934:Glucagon / Q000097:blood*; D006801:Humans; D007106:Immune Sera; D007124:Immunoenzyme Techniques; D008832:Microchemistry; D010179:Pancreas / Q000032:analysis*; D010446:Peptide Fragments / Q000032:analysis; D001616:beta-Galactosidase
D007106:Immune Sera; D010446:Peptide Fragments; D005934:Glucagon; D005696:Galactosidases; D001616:beta-Galactosidase