title: Improved substrate-labeled fluorescent immunoassay for theophylline in dried-blood spots on filter paper.
mesh_terms: D001322:Autoanalysis; D001800:Blood Specimen Collection / Q000379:methods; D005374:Filtration / Q000295:instrumentation; D005455:Fluorescent Antibody Technique; D006801:Humans; D006863:Hydrogen-Ion Concentration; D013806:Theophylline / Q000097:blood*
chemical_list: D013806:Theophylline