An Order of Magnitude Improvement in Detection Limits Achieved by Using a New Sample Support in Small Spot Xrf Analysis.

Abstract

A new sample support film for small spot XRF analysis has been developed that improves detection limits by a factor of 10 over traditional polymer supports. The surface characteristics of this new film are excellent for retaining drops of sample solution in one place and allowing the solution to dry into a single spot A dimpling technique was developed to further aid in concentrating the evaporated samples to the prescribed spot size and position. The film showed good resistance to chemical attacfc from the solution, even some strong acids and bases. The detection limits achieved using micro sample XRF with the ultra thin sample support were sufficient to be a comparable alternative to ICP-MS and GFAAS for elemental analysis.

Automated printing technology as a new tool for liquid sample preparation for micro x‐ray fluorescence (MXRF)

“…Hydrophobic AP1 has a thickness of only 0.2 µm and has been shown to be excellent for typical laboratory-based MXRF analysis of nanoliter dried spot residues owing to its low background and contamination characteristics. 5,6 The second substrate, Kapton, has a thickness of 7.5 µm. Kapton was chosen because of its robust strength characteristics in harsh environments, 14 which make it suitable for handling by unskilled users or for use in remote sampling applications that may be performed in the field with a portable MXRF instrument.…”

X-ray fluorescence spectrometry

“…Concerning the analysis of liquids, Nielson et al 349 offered an order of magnitude improvement in detection limits for trace elements in water by using a new sample support for retaining drops of sample solution in one place and allowing the solution to dry into a single spot. Wolska and Vrebos 350 also described the dimpling technique.…”

Optimization of a dried residue specimen preparation method for quantifying analytes in plutonium metal using WDXRF

“…Thus, the potential exists for radioactive solution to leak inside the instrument. The casting of solutions into dry residues for XRF analysis has been investigated by others for preconcentrating trace elements to improve the detection limits [3][4][5][6]. A similar dried residue technique was developed here to eliminate the need to analyze radioactive solutions [2,[7][8][9].…”

“…Thus, the potential exists for radioactive solution to leak inside the instrument. The casting of solutions into dry residues for XRF analysis has been investigated by others for preconcentrating trace elements to improve the detection limits ͑Colletti and Havrilla, 1999; Meltzer and King, 1991;Murata et al, 1984;Nielson et al, 1997͒. A similar dried residue technique was developed here to eliminate the need to analyze radioactive solutions ͑Worley, 2002͑Worley, ,2003Worley and Colletti, 2004;Worley and Havrilla, 2001͒.…”