Dr. G. J. Havrilla (Los Alamos National Lab., USA; one of the associate editors of X-Ray Spectrometry journal) and his colleague recently published a very interesting report on the analysis of picoliter droplets, which can be now accurately prepared using Hewlett-Packard's extremely sophisticated technology. The research targets application to analytical science, although the instrument is basically designed for inkjet printing and other similar purposes. It has been shown that dried deposits of single and multielemental solutions generated in picoliter volumes are able to be used as references for micro X-ray fluorescence. Evaporation can have a strong influence on extremely small amounts at the picoliter level, but the research group successfully devised the optimal instrumental conditions by monitoring X-ray fluorescence intensity. For more information, see the paper, "Picoliter droplet deposition using a prototype picoliter pipette: Control parameters and application in micro X-ray fluorescence", U. E. A. Fittschen et al., Anal. Chem., 82, 297 (2010).
