A comparison of elemental analysis techniques requiring no sample preparation: scanning electron microscopy and laser induced breakdown spectroscopy

Abstract

Elemental analysis on samples usually involves a preparation that dissolves the sample. Two analytical techniques which enable solid phase elemental analysis are scanning electron microscopy–energy dispersive X-ray emission (SEM-EDX or simply SEM) and laser induced breakdown spectroscopy–optical emission spectroscopy (LIBS-OES or simply LIBS). Each of these techniques is capable of determining the elemental composition of the sample by looking at electron relaxation after excitation and they are compared in this study. SEM and LIBS were used to examine two samples chosen from consumer health care products, an antacid and an acid reducer. This work showed that both techniques could successfully detect active, calcium and chlorine, and inactive ingredients. While both analytical techniques were successful in detecting the elements of interest, a direct comparison of the results is difficult due to the fundamental nature of the two measurements.