The detection of Melamine and Cyanuric acid in foodstuffs can be readily performed at the 30ug/kg level using a new method that has been developed by US FDA scientists
The new method was created by the US FDA Center for Food Safety and Applied Nutrition at College Park, Maryland, USA.
Both Melamine and Cyanuric acid have been linked to kidney failure in animals.
The method involves extraction of the sample with aqueous acetonitrile, followed by solid phase extraction, separation via a SeQuant ZIC- HILIC hydrophilic interaction chromatographic column and detection via a triple quad MS-MS detector.
The method is linear from 2ng/ml to 200ng/ml (7 points, r 2 = 0.999).
Since acceptable recoveries of the compounds of interest from fortified pork were obtained (87-107 percent), matrix effects do not appear to be significant.
The method is now being validated for fish and the method is being extended to beef and poultry.
The authors found that the ZIC- HILIC column was required to obtain the separation.
Reverse phase columns were not capable of retaining the analytes and other HILIC columns were good for one of the compounds of interest but was less useful for the other (for example a weak anion exchange HILIC column was useful for cyanuric acid but not for melamine).
ZIC-HILIC is a versatile stationary phase for HPLC that is based on bonding of zwitterionic sulfobetaine groups to the silica backbone.
It has many of the characteristics of a normal phase, but allows for a significant aqueous fraction in the mobile phase, thereby providing for greater solubility of polar analytes and greater sensitivity.
