Procedure for sample decomposition and AES measurement

Place 0.1000 g of sample into a 30-ml plastic jar having a screw cap. Add 5 ml of cold water and tiien 5 ml of cold 29 M HF. Cap tightly and set aside at room temperature until dissolution is complete (1—24 h). Nearly all silicate glass samples do not require heat for dissolution, but if heat is applied then a viable seal must be assured in order to prevent Ihe loss of boron as the fluoride. (Insoluble fluorides and unreactive oxides may remain 

The authors express their appreciation to Mr. G. A. Machajewski, Mr. D. O. Robinson, Mr. S. D. Solsky, Ms. M. Snyder and Mr. W. C. Thresher who performed laboratory experiments that helped make this publication possible. 

The early 1960 s saw the introduction of flame atomic absorption spectrometry (AAS) to clinical laboratories and this provided a sensitive yet simple analytical technique for the estimation of some trace elements in biological fluids. Trace elements is now perhaps an inaccurate description for those metals previously detectable in only small amounts when using older and less sensitive analytical techniques. Many such elements can now be estimated with precision and this has proved a great stimulus to trace-element research in clinical medicine. The number of trace elements known to be essential to man has doubled in the last twenty years [1]. Specific and treatable diseases are now known to be associated with excess or deficiency of trace elements and even in advanced societies dietary intake of some elements may be less than ideal [2]. Thus, monitoring of biological fluids for trace element levels in both health and disease can contribute towards major advances in nutritional management. 

This chapter considers the optimisation of both physiological and analytical conditions for the estimation of those elements present in biological fluid best suited to analysis by flame AAS. 

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