title: Measurement of serum digitoxin in patients by radioimmunoassay using specific antiserum.
abstract: BACKGROUND
  Digitoxin is used to treat patients with heart failure.
  
  
  METHODS
  A radioimmunoassay procedure for the specific determination for digitoxin in serum was developed using the antiserum (antiserum (A)) raised against digitoxin 3'-hemisuccinate-BSA conjugate.
  
  
  RESULTS
  The intra- and interassay variability were <10% in the range of 5-100 ng/ml. The specificities of antiserum (A) and the commercial anti-digitoxin antiserum (antiserum (B)) were assessed by cross-reactivity studies with various related compounds. Antiserum (A) was highly specific for digitoxin. Mean digitoxin concentrations in serum samples (n=34) from digitalized patients by RIA using these antisera were 10.0 and 12.4 ng/ml, respectively.
  
  
  CONCLUSIONS
  This RIA using antiserum (A) measure unmetabolized digitoxin and may be applicable for pharmacokinetic studies.
authors.affiliation: Faculty of Pharmaceutical Sciences, Hokuriku University, Ho-3, Kanagawa-machi, Kanazawa 920-1181, Japan. y-ikeda@hokuriku-u.ac.jp
authors.forename: Y
authors.initials: Y
authors.lastname: Ikeda
authors.forename: M
authors.initials: M
authors.lastname: Fujii
authors.forename: M
authors.initials: M
authors.lastname: Yamazaki
authors.forename: Y
authors.initials: Y
authors.lastname: Fujii
mesh_terms: D000818:Animals; D000906:Antibodies / Q000032:analysis; D000918:Antibody Specificity; D002316:Cardiotonic Agents / Q000097:blood* / Q000276:immunology; D003429:Cross Reactions; D004073:Digitoxigenin / Q000097:blood; D004074:Digitoxin / Q000097:blood* / Q000276:immunology; D006333:Heart Failure / Q000097:blood; D006801:Humans; D011817:Rabbits / Q000276:immunology; D011863:Radioimmunoassay; D015203:Reproducibility of Results; D012710:Serum Albumin, Bovine / Q000737:chemistry
chemical_list: D000906:Antibodies; D002316:Cardiotonic Agents; D004073:Digitoxigenin; D012710:Serum Albumin, Bovine; D004074:Digitoxin