RESUMO
The article presents the results of experimental studies on the development of highly sensitive and selective chromatography-mass spectrometry technique for the determination of 9 N-nitrosamines in food samples (sausage products) using distillation and an automatic solid-phase extraction system on Coconut cartridges for sample preparation. In the elaborated conditions of sample preparation (distillation and solid-phase extraction) and chromatography-mass spectrometric analysis, we achieved a high recovery and efficiency of the separation of nine N-nitrosamines. The quantitation limit was at level of 0.0002 mg/kg with maximum error not exceeding 19%. The complex use of the distillation of N-nitrosamines with the addition of potassium hydroxide in combination with the optimal elution scheme for solid-phase extraction and concentrating the distillate into a Coconut carbon cartridge of 6 ml ensures the recovery of N-nitrosamines from the food product sample (sausage products) up to 93.2-100%. The process of approbation of the chromatography-mass spectrometric method in the samples of food products (sausage products) of various manufacturers revealed the content of N-nitrosamines in the concentration range 0.00029±0.000055÷0.350±0.05 mg/kg. The conducted studies of the content of the sum of highly toxic N-nitrosamines (N-nitrosodimethylamine, N-nitrosodiethylamine) made it possible to disclose that in sample No. 5 the maximum allowable concentration was exceeded by 47 times, in samples No. 2 and 16, to 57.5 and 22.9 times and in sample No. 4 to 88 times, respectively.