Analysis of Sulfamic Acid in Fertilizers Using LC/MS (LCMS-2020)

Introduction

Sulfamic acid, due to its plant growth inhibiting effects, is subject to maximum limits in fertilizers as specified in the official standard for ordinary fertilizers according to the Japanese Fertilizers Regulation Act. According to the Testing Methods for Fertilizers supervised by Japan's Food and Agricultural Materials Inspection Center (FAMIC), the ion chromatography (IC) method is specified as the test method for sulfamic acid in ammonium sulfate. It has been reported, however, that when applying this IC method with byproduct compound fertilizer (fertilizer produced by concentrating and drying liquid byproducts obtained from fermentation plants involved in amino acid production, etc.) samples that contain large amounts of organic matter, it is difficult to separate the sulfamic acid peaks from contaminant peaks generated from sample matrix. In this application, we investigated the analytical conditions for LC/MS that would permit acquisition of mass information and provide high selectivity in order to eliminate the effects of contaminating components. The LCMS-2020 single quadrupole mass spectrometer was used for the analysis. Good quantitative results were obtained, confirming the applicability of this method using byproduct compound fertilizer as the actual sample.

April 6, 2015 GMT