Test Catalog Search Home Test Catalog Search Testing Choices: From the standard to the extraordinary × Search Clear Filter by: Clear all Method(s) High Performance Liquid Chromatography/Tandem Mass Spectrometry (LC-MS/MS) (1) (-) Spectrophotometry (SP) (2) Sample Type Blood (1) RBCs (1) Test Area Exposure (2) Test Category Analgesics (4) Antiarrhythmics (2) Anticholinergics (6) Antiepileptics/Antiseizures (2) Antimigraines (3) (-) Biomarkers (2) Immunosuppressants (1) Opiates/Opioids (3) Pesticides/Insecticides (5) Sedative/Hypnotics (2) Vasodilators (3) Volatiles (1) Test Sub-Category (-) Other (2) Test Test Name 4235B Sulfhemoglobin, Blood 4235R Sulfhemoglobin, RBCs