Solid-phase double-antibody radio-immunoassay for atrial natriuretic factor.
A solid-phase radio-immunoassay for the determination of atrial natriuretic factor (ANF) in human plasma is described. Iodination of alpha hANF was carried out with the iodogen method. Purification of radio-iodinated alpha hANF was performed by chromatography on disposable columns of DEAE-Sephadex A-25. Studies of immunoreactivity and the elution pattern on HPLC showed perfect stability of the labelled compounds. The tracer was usable for 28 weeks after preparation, and the batch-to-batch variation in the quality of the tracer was satisfactory. Immunoreactive ANF was extracted from human plasma with Sep-Pak C18 cartridges. Recovery of alpha hANF added to whole blood was 85 +/- 12% (mean +/- SD, n = 12). The sensitivity of the radio-immunoassay was 1.6 pg/tube, equivalent to 1 pg/ml plasma when assaying the extract from 4 ml plasma. Mean plasma ANF values in normal subjects in the supine position was 23 +/- 12 pg/ml (mean +/- SD, n = 21).
Rasmussen
P H
PH
Department of Clinical Physiology and Nuclear Medicine, Glostrup Hospital, University of Copenhagen, Denmark.
Nielsen
M D
MD
Giese
J
J
D009320:Atrial Natriuretic Factor / Q000097:blood*; D002851:Chromatography, High Pressure Liquid; D003080:Cold Temperature; D006801:Humans; D007457:Iodine Radioisotopes; D007553:Isotope Labeling; D008832:Microchemistry; D011863:Radioimmunoassay; D012016:Reference Values; D013997:Time Factors
D007457:Iodine Radioisotopes; D009320:Atrial Natriuretic Factor