Seminars

Megapixels per minute: fast efficient X-ray fluorescence microscopy at the Australian Synchrotron

Abstract: X-ray fluorescence microscopy (XFM) can be used for elemental and chemical microanalysis across length scales ranging from millimeter to nanometer. XFM is ideally suited to quantitatively map trace elements within whole plant and animal, biological specimens and environmental samples. The high elemental sensitivity of X-ray fluorescence microprobe combined with deep penetration of hard X-rays allows measurement of a diverse range of samples with a minimum of preparation. X-ray fluorescence microscopy (XFM) can be used for elemental and chemical microanalysis across length scales ranging from millimeter to nanometer. XFM is ideally suited to quantitatively map trace elements within whole plant and animal, biological specimens and environmental samples. The high elemental sensitivity of X-ray fluorescence microprobe combined with deep penetration of hard X-rays allows measurement of a diverse range of samples with a minimum of preparation.

Event mode X-ray fluorescence detection methods pioneered by the Maia detector system at the Australian Synchrotron XFM beamline enables high definition XRF imaging approaching megapixel per minute rates. An introduction to event mode XRF data acquisition, fast scanning techniques and analysis methods, along with correlated techniques particularly ptychography will be given. Some examples of fast XFM from the macro scale – meter square paintings, to the micron scale – entire small plants, will be presented.

The ability to rapidly acquire 2D images enables higher-dimensional studies such as fluorescence tomography, X-ray absorption near edge structure (XANES) imaging, and XANES tomography in realistic time frames. Full spectral XANES imaging takes advantage of fast XFM and results in X-ray absorption near edge structure spectra from X-ray fluorescence at each pixel in an image. I will present some examples where fluorescence imaging XANES has been used to visualize in vivo coordination environments of metals in biological specimens and study arsenic toxicity in crop production