# 5-Amino-1MQ Purity Testing: What Independent Labs Actually Check
5-Amino-1MQ (5-amino-1-methylquinolinium) is a small-molecule NNMT inhibitor being studied in metabolic and adipose tissue research. It is not a peptide. This matters because the analytical playbook for a peptide (HPLC at 214 nm, LC-MS deconvolution) is not the right playbook for a quaternary ammonium small molecule.
What 5-Amino-1MQ actually is
- Molecular formula: C10H11N2+ (as the cation)
- Molecular weight: 159.21 g/mol (cation)
- Commonly supplied as the iodide salt, total salt-form mass ~286 g/mol
- UV chromophore: strong absorbance in the 250-350 nm range, not 214 nm
Because it is charged and small, it behaves nothing like a peptide on standard reversed-phase methods.
The right analytical approach
HPLC purity. C18 with an appropriate ion-pair reagent (heptafluorobutyric acid works well for small quaternary amines) or a HILIC column. Detection at 254 nm or 280 nm, not 214 nm.
Identity by LC-MS. Positive mode ESI. Look for the [M]+ ion at m/z 159. If the sample is supplied as the iodide salt, the counterion is measured separately by ion chromatography or an orthogonal iodide-specific method.
Salt form confirmation. Buyers assume iodide; some suppliers ship chloride or trifluoroacetate. The salt form affects mass calculations, solubility, and dosing. Ion chromatography or NMR confirms the counterion.
Related substances. Known byproducts: the desamino analog, the N-methyl-only intermediate, and starting material carryover.
Water content. Karl Fischer. Quaternary ammonium salts are hygroscopic.
Residual solvents. DMF and DMSO are common in the synthesis. GC-MS confirms clearance.
