title: Development of a radioimmunoassay for theophylline. Application to studies in premature infants.
abstract: The use of theophylline in premature infants has necessitated the development of an assay applicable to samples under 0.1 ml. To accomplish this we have developed a radioimmunoassay for theophylline. The antiserum to theophylline has been characterized and found to be highly specific for theophylline and sensitive to 2 ng. The affinity of our antibody and the titer developed in the goat allowed the assay to be performed routinely with the use of a plasma sample size of only 2 to 5 micronl. Theophylline levels of 6 to 20 microng/ml were found 2 hr after maintenance doses of aminophylline, 4 mg/kg per rectum in 12 premature infants. Terminal serum half-lives ranged from 12 to 54 hr.
mesh_terms: D000628:Aminophylline / Q000378:metabolism / Q000627:therapeutic use; D000818:Animals; D000918:Antibody Specificity; D001049:Apnea / Q000097:blood / Q000188:drug therapy; D001667:Binding, Competitive; D003429:Cross Reactions; D006041:Goats / Q000276:immunology; D006801:Humans; D007231:Infant, Newborn; D007235:Infant, Premature, Diseases / Q000097:blood* / Q000188:drug therapy; D008722:Methods; D011863:Radioimmunoassay; D013806:Theophylline / Q000097:blood*; D013997:Time Factors
chemical_list: D000628:Aminophylline; D013806:Theophylline