A formed filter paper medium for microdroplet analyses of liquid samples by X‐ray fluorescence spectrometry

Abstract

Abstract A new type of a formed filter paper is proposed as a sample medium for a microdroplet analysis by x‐ray fluorescence spectrometry. It has a circular center part, separated by a narrow circular groove from its edge, and four, paraffined, supporting bridges. It can thus keep a spot area constant when a liquid sample drops at the center part. After dropping the liquid sample, the paper is dried and used for the x‐ray measurement. It can be stored for years without any chemical change. This formed filter paper is effective in improving the linearity range of a calibration curve and the precision of a fluorescent x‐ray measurement as compared with a non‐formed filter paper. The sample volume required is only 20 to 100 μ1 and therefore microscale analysis of the liquid sample is allowable.