Fig. 2:

Schematic of the XAS setup using the DOT (Drop-on-Tape) method. Use of ADE (acoustic droplet ejector) to deposit samples in ∼250 μm droplets reduces sample consumption which facilitates the collection of data for <1 mM metal concentration in biological samples. Total fluorescence from the sample is collected with an ePix detector directly above the droplet from the droplet-XFEL interaction point. A forward scattering detector collects scattering from the solvent that is used for normalization. Figure expanded from original publication in Chatterjee et al. 2019 [9].