A METHOD TO EXTEND THE APPLICATION OF MICRODROPLET TECHNIQUES IN THE SEM

A thin-film method of microdroplet analysis is described. The method d iffers from those published previously. First, uniformly distributed a morphous deposits of chemicals were obtained through the use of a non- aqueous anticrystallization agent, ethylene glycol, which has not been described previously. Second, films of celloidin were used; these cou ld be prepared routinely at 60-80 nm and contained no interfering elem ents. Initially, these films were too unstable to be of use, but heati ng them at 60-degrees-C greatly improved their stability. A nebulizer was used to deliver microdroplets to these supports, which were, in tu rn, supported by a specially constructed carbon holder. Minimum detect able concentrations were improved with this method.