A sandwich transfer enzyme immunoassay for salmon calcitonin: Determination of the bioavailability of intranasal salmon calcitonin in human

✍ Scribed by Takeyuki Kohno; Noriaki Murasugi; Hiroki Sakurai; Kazuhito Watabe; Hiromichi Nakamuta; Masao Koida; Yohko Sugie; Masakatsu Nomura; Akira Yanagawa

• Publisher: John Wiley and Sons
• Year: 1997
• Tongue: English
• Weight: 78 KB
• Volume: 11
• Category: Article
• ISSN: 0887-8013
• DOI: 10.1002/(sici)1098-2825(1997)11:6<380::aid-jcla13>3.0.co;2-s

✦ Synopsis

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.