A low-cost, high-performance method for the production of particles to trace water flow with high contrast in XROMM studies.

Dynamic X-ray imaging has proved to be a useful method for tracing particles in otherwise obscured areas. Through the combination of X-ray Reconstruction of Moving Morphology (XROMM) with X-ray Particle Tracing Velocimetry (XPTV), new insights in functional morphology can be gained. Creating particles with desired properties as neutrally buoyant but yet different from water in their attenuation of X-rays has proved to be a crucial but challenging task. This paper describes a simple and low-cost protocol for the manufacture of XPTV particles of specific diameters to fit the application. This is achieved through a novel approach where the particles are made from a homogeneous mixture, allowing them to be shaped as needed, in contrast to existing solutions that rely on assemblies of at least two precisely dimensioned components. The proposed approach satisfies key characteristics, including high X-ray attenuation, uniform shape and specified effective density, and outperforms current state-of-the-art solutions.