Method for determining organic mercury in food by combining ion chromatography with inductively coupled plasma mass spectrometer

Abstract

The invention is applicable to the technical field of biological detection, and provides a method for determining organic mercury in food by combining an ion chromatography with an inductively coupledplasma mass spectrometer. The method comprises the steps of: performing pre-treatment on a sample; separating methyl mercury, ethyl mercury, and inorganic mercury in the sample by the ion chromatography; sending the sample into the inductively coupled plasma mass spectrometer for analysis to obtain spectrograms of the methyl mercury, the ethyl mercury, and the inorganic mercury; the operating parameter of the ion chromatography comprises duration 260-270s; the operating parameters of the inductively coupled plasma mass spectrometer comprises: RF Power 1550W; atomizing gas 0.95 to 1.15L / min; QCell Gas 3.35 to 5.50mL / min; Collision Mode Voltage: 3.0V; and Residence Time 200 to 220ms; and finally, preparing a working curve, and calculating the detection limit. According to the method for determining organic mercury in food by combining the ion chromatography with the inductively coupled plasma mass spectrometer, the detection limit of organic mercury in the food is low, and the analysissensitivity is high; the detection equipment is stable and high in precision; the operation is simple; and the cost is low.

Description

technical field [0001] The invention relates to the technical field of biological detection, in particular to a method for determining organic mercury in food by combining ion chromatography and inductively coupled plasma mass spectrometer. Background technique [0002] With the wide application of mercury in industry, agriculture, medicine, etc., the pollution problem caused by mercury and its compounds is becoming more and more serious, and mercury pollution has become a major public hazard to the human living environment. For example: the discharge of mercury-containing industrial wastewater has made river water more and more serious, and aquatic animals in river water, such as fish and shellfish, are very easy to absorb mercury, and mercury is enriched into various aquatic animals through biological chains; Sewage irrigation, sludge fertilization or application of mercury-containing pesticides enriches mercury into crops; when humans eat aquatic animals and crops, mercur...

AI Technical Summary

Problems solved by technology

[0003] Mercury exists mostly in the form of organic mercury in animals and plants, such as methylmercury or ethylmercury. At present, there are many detection methods for organic mercury, usually using liquid chromatography-atomic fluorescence spectrometry. During the detection process, it is necessary to Digester, tissue homogenizer, pulverizer, centrifuge and other pre-treatment equipment are used; methanol, ammonia water, hydrochloric acid, ammonium acetate, potassium persulfide, potassium borohydride, sodium hydroxide, potassium hydroxide and other reagents are also required. Moreover, these reagents need to be of superior grade or even higher than chromatographic purity, with a lot of consumables and high cost; in the detection process, a variety of solutions and mobile phases need to be configured, the operation is complicated, time-consuming and labor-intensive

[0004] In addition, the detection limits of existing detection methods are generally relatively high. For example: CN104777139B discloses a method and application for simultaneously detecting total mercury, inorganic mercury and organic mercury in tobacco. The detection limit of total mercury, inorganic mercury and organic mercury in the sample is 26.7 μ g / kg, 21.6 μ g / kg and 25.0 μ g / kg respectively; CN101158667B discloses a kind of method for detecting organic mercury compound, adopts liquid chromatography- The detection limits of inorganic mercury, methylmercury, ethylmercury and phenylmercury in fish and shellfish samples by atomic fluorescence spectrometry are 0.22, 0.53, 0.18 and 0.25 μg / L respectively; the existing technology generally cannot detect Foods with low organic mercury content can be detected by some methods, but the cost is high and the operation is complicated. Therefore, we need an instrument with higher precision, lower detection limit, simple operation and low cost to detect Organic Mercury Content

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