T 1461 (OTTO) Tetramethylammonium hydrogen sulphate, for HPLC 99% Cas 80526-82-5 - used as a phase transfer catalyst. T 1461 (OTTO) Tetramethylammonium hydrogen sulphate, for HPLC 99% Cas 80526-82-5 - used as a derivatizing agent for gas chromatography-mass spectrometry (GC-MS) applications.