METHOD FOR MEASURING THE MASS CONCENTRATIONS OF ALUMINUM, ARSENIC, STRONTIUM, CADMIUM, LEAD, MERCURY IN FLOUR, CEREALS AND BAKERY PRODUCTS BY INDUCTIVELY COUPLED PLASMA MASS SPECTROMETRY Russian patent published in 2022 - IPC G01N33/02 G01N33/10 

FIELD: analytical chemistry.

SUBSTANCE: invention relates to the field of analytical chemistry. The method for measuring mass concentrations of aluminum, arsenic, strontium, cadmium, lead, mercury in flour, cereals and bakery products by inductively coupled plasma mass spectrometry is characterized by the fact that sampling is performed, sample preparation is performed, and after sample preparation, the prepared sample is introduced into the sampling device mass spectrometer with inductively coupled plasma, measure and determine the content of a particular metal using a calibration curve. At the same time, at the stage of sample preparation, 6.5 cm³ of concentrated nitric acid is added to a sample weighing 0.5 g, then 0.5 cm³ of concentrated hydrochloric acid is added, and the mixture is kept for 90 minutes. Next, the autoclave with the introduced sample is closed and installed in a microwave sample preparation system, where the sample is decomposed to obtain a mineralizate at a pressure of 4 MPa in three stages. Moreover, at the first stage at a temperature of 120°X for 5 min; at the second stage at 140°C for 10 min; at the third stage at 170°C for 5 min. Then, 0.5 cm³ of the resulting mineralizate and 4.40 cm³ of deionized water are introduced into the sampling device of an inductively coupled plasma mass spectrometer. Measurements in the prepared sample of the content of a particular metal in the mass spectrometer are carried out using a reaction/collision cell when helium is passed through it as a reactant gas at a rate of 4.2-4.5 cm³/min and a complex solution of internal standard with a mass concentration of the reference elements terbium, indium and germanium, 100 mcg/dm³ each in a volume ratio of mineralizate:standard as 1:0.1. At the same time, an internal standard solution with a mass concentration of 100 mcg/dm³ of the rhodium reference element is additionally introduced in the mineralizate:standard volume ratio as 1:0.1. Determination of the content of a particular metal is carried out using a calibration curve.

EFFECT: invention makes it possible to determine the content of aluminum, arsenic, strontium, cadmium, lead, mercury in flour and cereals and bakery products from one selected sample.

1 cl, 10 tbl