title: Radioimmunoassay of somatomedin-C in filter paper discs containing dried blood.
abstract: We describe a simple radioimmunoassay (RIA) for estimating concentrations of somatomedin-C (Sm-C) in dried blood on filter paper. A single 3.2-mm blood spot specimen on filter paper is eluted overnight into buffer containing antibody and 125I-labeled Sm-C. The following day, bound and free hormones are separated by addition of goat anti-rabbit gamma globulin in 60 g/L polyethylene glycol solution. The correlation between values obtained for such blood-spot discs and the corresponding wet plasma is highly significant (r = 0.90, p less than 0.001). The relative concentrations (arbitrary units) of Sm-C as determined for specimens on filter paper from mothers and infants, and for cord bloods, are similar to those reported by others using acidified serum.
mesh_terms: D000328:Adult; D003890:Desiccation; D005260:Female; D005374:Filtration; D006801:Humans; D007231:Infant, Newborn; D007334:Insulin-Like Growth Factor I / Q000097:blood*; D010209:Paper; D011863:Radioimmunoassay / Q000379:methods; D013002:Somatomedins / Q000097:blood*
chemical_list: D013002:Somatomedins; D007334:Insulin-Like Growth Factor I