A new sensitive HPLC assay for methoxyamine and its analogs.

Methoxyamine (MOA) and its analogs are polymerization regulators, building blocks and intermediates for agrichemicals and pharmaceuticals. MOA induces mutagenesis of nucleic acids and has been considered for anti-cancer and anti-virus therapy. It has been studied as a DNA repair modifier in anti-cancer therapy. HPLC procedures available in the literature for MOA are all based on electrochemical detection, which is not commonly available. This paper describes the development and validation of a HPLC assay with UV detection for MOA and its analogs. The analytes are first reacted with o-phthalaldehyde to form an oxime derivative before chromatography with an ODS column. Detection is achieved by UV at 254 nm. The chromatography resolves MOA from its decomposition products and analogs. The assay is reproducible (R.S.D. < 0.8%), linear (r(2) = 0.9997), and accurate (error < 1%). The method is sensitive and has a lower detection limit of 5 pmol (0.4 ng of MOA.HCl), which is comparable to that of electrochemical detection.