5 mtam

Sodium acetate, disodium EDTA (Ethylene Diamine Tetraacetic Acid) and acetic acid (all of the highest chemical purity) were purchased from J.T. Baker Chemicals (Phillipsburg, NJ, USA). Methanol of gradient-grade HPLC purity and perchloric acid were obtained from Merck Millipore (Billerica, MA, USA). TRP, 5-HTRP, 5-HT, NAS, MLT, 5-HIAA, 5-MIAA, 5-MTOL, and 5 MTAM were bought from Sigma-Aldrich (St. Louis, MO, USA). 5-HTOL was obtained from Santa Cruz Biotechnology (Dallas, TX, USA). Ultrapure water (18.2 MΩ, TOC ≤ 5 ppb) was freshly prepared using a Milli-Q Integral purification system (Merck Millipore, Billerica, MA, USA) and used in all analytical procedures.

Methanol of gradient-grade high pressure liquid chromatography (HPLC) purity, ammonium iron (II) sulfate hexahydrate, and perchloric acid were provided by Merck Millipore (Billerica, MA, USA). Sodium acetate, sodium dihydrogen phosphate, sodium monohydrated phosphate, disodium EDTA, and acetic acid were purchased from J. T. Baker Chemicals (Center Valley, PA, USA). Tetrahydrobiopterin, dithiothreitol, 3-hydroxybenzylhydrazine dihydrochloride (NSD-1015), catalase from bovine liver, TRIS base, pyridoxal 5’-phosphate hydrate, pargyline, 5-tryptamine, acetyl-CoA sodium salt, S-adenosylmethionine, TRP, 5-HTRP, 5-HT, NAS, MLT, 5-HIAA, 5-MIAA, 5-MTOL, and 5 MTAM were obtained from Sigma-Aldrich (St. Louis, MO, USA). 5-HTOL and 5-MTRP were purchased from Santa Cruz Biotechnology (Dallas, TX, USA). Ultrapure water (18.2 MΩ, TOC ≤ 3 ppb), which was freshly prepared using a Milli-Q^® IQ 7003/05 purification system (Merck Millipore, Billerica, MA, USA), was used in all procedures.