Test Catalog Search Home Test Catalog Search Testing Choices: From the standard to the extraordinary × Search Clear Filter by: Clear all Method(s) Colorimetry (C) (2) Enzyme-Linked Immunosorbent Assay (ELISA) (2) Gas Chromatography/Mass Spectrometry (GC/MS) (2) Headspace Gas Chromatography (GC) (2) High Performance Liquid Chromatography/ Tandem Mass Spectrometry (LC-MS/MS) (1) (-) Inductively Coupled Plasma/Mass Spectrometry (ICP/MS) (1) Sample Type Blood (3) (-) RBCs (1) Serum or Plasma (3) Urine (3) Test Area Test Category Test Sub-Category Test Test Name 3784R Potassium - Total, RBCs