Emission Spectrometric Determination of Trace Metals in Biological Tissues

Abstract

An emission spectrometric method of analysis is described which permits duplicate analyses to be performed on 1-g specimens of tissue for 13 elements in the microgram percent range. Pig hearts were dissected into 17 separate pieces representing discrete anatomic sites. Samples were prepared for analysis by low temperature wet digestion. On the basis of their composition of the macro elements sodium, potassium, and phosphorus, these tissues could be divided into two groups: one including blood vessels and heart valves, and the other including ordinary and specialized myocardium. A method is described for adjusting the macro element composition of these tissues to that of a common matrix, thus allowing trace metal analysis of both groups of tissues to be performed using only a single set of standards. A solution of the ash was placed in hollow cup graphite electrodes with center posts, evaporated to dryness, and analyzed in the dc arc with a Jarrell-Ash model 66,000 direct reading emission spectrometer. At concentrations above 10 µg%, the coefficient of variation was about 10% for most of the trace metals studied.