SAF Coprecipitation Systems Of Cu,Mn,Cr And Pb In Food And Dairy Products By Using Flame Atomic Absorption Spectrometry Determination

Compared with the past,contemporary society with the rapid development of science and technology,the basic necessities of human lives likewise had the qualitative changes.However,at the same time as these situations have transformed,the additives,pigments,pesticides and other toxic chemicals that threatened human lives' safety have appeared,which made people enhance to protect themselves strongly,also pay more attention to living environment and food safety issues.Therefore a variety of checkout equipments and detection methods emerged as the times required.For determination of trace metal elements in the samples,it is sometimes necessary to achieve such a high sensitivity level as ppb,the instruments with higher sensitivity level applied to the actual production always could not satisfy the inspection requirements,meanwhile high sensitivity instruments were so expensive that many testing laboratories or testing organizations could not afford.As a result,everything was taken into consideration,we should set out from the ordinary instrument level to improve the selectivity and sensitivity involved in detection methods,hence adopted the co-precipitation method to act on separation and enrichment.Co-precipitation method has the advantages of handling simply and fast,high enrichment factor,what's more,it is a pretreatment method that was widely applied in separation and enrichment,which could reduce costs and detection limit,improve the sensitivity combined with flame atomic absorption method.For researching on the analysis process of the trace metal content's determination,this paper used of salicyl fluorone?SAF?as the medium of co-precipitation for the first time,and chose Fe???,Al???,Ba???ions as carriers.Co-precipitation separated and enriched copper,manganese,chromium,lead in food and dairy products by using flame atomic absorption spectrometry to assay the content of the above four types of trace heavy metals.In this experiment,the optimal co-precipitation systems were obtained by optimizing the selection of carrier ions,the dosage of co-precipitation agent,total precipitation for the amount of time,sample volume,solution pH,interference of coexisting ions content restrictions etc.according to analyzing the method of sensitivity,detection limit,precision,etc.which discussed the advantages of the method.This paper studied the determination of trace heavy metals from the following four systems:1.Fe???-SAF co-precipitation system to detect Cu.The sensitivity of the method is 0.4370?mg/L?^-1,for precision is 1.03%,the detection limit is 1.26 ?g/L.2.Al???-SAF co-precipitation system to detect Mn.The sensitivity of the method is 1.1628?mg/L?^-1,for precision is 0.52%,the detection limit is 0.38?g/L.3.Al???-SAF co-precipitation system to detect Cr.The sensitivity of the method is 0.2637?mg/L?^-1,for precision is 2.47%,the detection limit is 2.09?g/L.4.Ba???-SAF co-precipitation system to detect Pb.The sensitivity of the method is 1.4265?mg/L?^-1,for precision is 1.73%,the detection limit is 0.46?g/L.The four systems for heavy metal ions involved Cu²⁺,Mn²⁺,Cr3+,Pb²⁺ have a good effection on separation and enrichment,which could basically eliminate the matrix interference.The experimental method with some advantages has simple operation,low detection limit,the cheap price,etc.It provided a new analysis method for the flame atomic absorption spectrometry of metal content in the food and dairy products.