Characterization of a submicro-X-ray fluorescence setup on the B16 beamline at Diamond Light Source

Area of Science:

• Materials Science
• Analytical Chemistry
• Biophysics

Background:

• X-ray fluorescence (XRF) is a powerful elemental analysis technique.
• High-resolution XRF is crucial for analyzing microscale and nanoscale samples.
• Synchrotron-based XRF offers enhanced capabilities for sensitivity and resolution.

Purpose of the Study:

• To evaluate a novel X-ray fluorescence (XRF) setup at the Diamond Light Source B16 beamline.
• To characterize the performance of the XRF setup in terms of resolution, sensitivity, and detection limits.
• To demonstrate the applicability of the XRF setup for biological sample analysis.

Main Methods:

• Testing of an XRF setup using two excitation energies (12.7 and 17 keV) at the B16 beamline.
• Characterization of beam size using a 50 µm gold wire, achieving 500 nm x 600 nm resolution.
• Measurement of sensitivities and detection limits for Arsenic Kα (As Kα) using 17 keV excitation.

Main Results:

• The XRF setup demonstrated sub-micrometer resolution, with a beam size of 500 nm x 600 nm.
• Achieved high sensitivity (249 counts s⁻¹ fg⁻¹) and low detection limits (4 ag in 1000 s) for As Kα.
• Successful measurements were performed on biological samples, including human bone and a single cell.

Conclusions:

• The tested XRF setup offers high spatial resolution and excellent sensitivity for elemental analysis.
• The demonstrated performance highlights the setup's suitability for analyzing thin samples, including biological specimens.
• This synchrotron-based XRF system provides a valuable tool for microscale and nanoscale elemental mapping in diverse research fields.