A sandwich transfer enzyme immunoassay for salmon calcitonin (SCT) and its usability for the pharmacokinetic study are described. The assay procedure consisted of the reaction of SCT with 2,4‐dinitrophenyl biotinyl anti‐SCT IgG and anti‐SCT Fab′‐β‐D‐galactosidase conjugate, trapping onto (anti‐2,4‐dinitrophenyl bovine serum albumin) IgG‐coated polystyrene balls, eluting with ϵN‐2,4‐dinitrophenyl‐L‐lysine and transferring to streptavidin‐coated polystyrene balls and fluorometric detection of β‐D‐galactosidase activity. The practical detection limit of SCT was 0.05 pg (15 amol)/50 μl of sample and 1 pg/ml as the concentration. The application of this method has enabled us to directly estimate the bioavailability of SCT dosed intranasally at the therapeutic level (160 IU, 31 μg) for its anti‐osteoporotic effect as compared to an intramuscular dose (10 IU, 1.9 μg). The pharmacokinetic parameters of the intranasal SCT (n = 6) thus estimated were as follows: the area under the blood concentration‐time curve (AUC) = 9400 ± 5400 (SD) pg·h/ml, and the mean residence time (MRT) = 42 ± 14 (SD) min, when the AUC for the intramuscular SCT (n = 3) = 5600 ± 2000 (SD) pg·h/ml and the MRT = 39 ± 19 (SD) min. J. Clin. Lab. Anal. 11:380–387, 1997. © 1997 Wiley‐Liss, Inc.
No abstract.