Nanoscale quantification of intracellular element concentration by X-ray fluorescence microscopy combined with X-ray phase contrast nanotomography

Abstract

We present here a correlative X-ray microscopy approach for quantitative single cell imaging of molar concentrations. By combining the elemental content provided by X-ray fluorescence microscopy and the morphology information extracted from X-ray phase nanotomography, we determine the intracellular molarity distributions. This correlative method was demonstrated on a freeze-dried human phagocytic cell to obtain the absolute elemental concentration maps of K, P, and Fe. The cell morphology results showed a very good agreement with atomic-force microscopy measurements. This work opens the way for non-destructive single cell chemical analysis down to the sub-cellular level using exclusively synchrotron radiation techniques. It will be of high interest in the case where it is difficult to access the morphology using atomic-force microscopy, for example, on frozenhydrated cells or tissues. V

3D multiscale imaging of human vocal folds using synchrotron X-ray microtomography in phase retrieval mode

“…Another solution could be to use chemical markers able to track one specific fibrous protein 29 , 45 . Last, we were not able to properly analyse the morphology of individual ECM fibres: this challenging task could be achieved by further increasing the spatial resolution of the images 46 .…”

Subcellular Chemical Imaging: New Avenues in Cell Biology

“…But overall, synchrotron X-ray Fluorescence (S-XRF) provides arguably the best combination of high spatial resolution capabilities (down to few 10 nm) and high sensitivity (sub-ppm) to light and heavy elements ( Figure 2, Box 1) [10,11]. S-XRF has allowed mapping and quantification of metals, such as Fe, Zn, Cu in microalgal and human cells [12][13][14], as well as silica, drugs, organometallic molecules, and titanium oxide nanoparticles in cancer cells [2,[15][16][17][18][19]. In combination with XRF imaging, X-ray Absorption Spectroscopy (XAS) can be performed in order to reveal the chemical speciation of a target element.…”

Cs-131 as an experimental tool for the investigation and quantification of the radiotoxicity of intracellular Auger decays in vitro

“…been confirmed for numerous mammalian cells. Thus it has been demonstrated that potassium is indeed equidistributed in fibroblasts, (Zierold et al 1984), human ovarian cancer (IGROV-1; Dev es and Ortega 2002) and yeast (Ortega et al 2004), pheochromocytoma (PC12; Kosior et al 2012), and human phagocytic cells (Gramaccioni et al 2018). Together these studies support the assumption of a homogeneous intracellular distribution of Cs-131.…”