title: Assay of unconjugated pteridines in biological fluids and tissues with Crithidia.
mesh_terms: D000818:Animals; D001681:Biological Assay; D001708:Biopterins / Q000032:analysis / Q000097:blood / Q000494:pharmacology; D003421:Crithidia / Q000187:drug effects*; D006801:Humans; D011621:Pteridines / Q000032:analysis* / Q000494:pharmacology
chemical_list: D011621:Pteridines; D001708:Biopterins