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Phantoms manufactured by 3D printers

New processing facility allows additive manufacturing of reference objects with embedded nanoparticles

PTB-News 2.2023
Especially interesting for

medical imaging

reference materials

additive manufacturing (3D printing)

A system for the synthesis of resinbased nanocomposites has been developed at PTB. It guarantees the defined and reproducible adjustment of the desired material composition for the 3D printing of medical phantoms.

This hand phantom fluoresces when irradiated with light of a certain wavelength. It is used by PTB to enhance medical measurement methods that help to detect pathologies such as rheumatoid foci by means of this fluorescence.

Medical and technical models with defined properties, so-called phantoms, are essential in medical imaging. In research and development projects, they serve as reliable reference systems for testing new applications or optimizing procedures. Phantoms are also used to verify the performance of imaging systems, thereby strengthening confidence in measurement results.

When compared with conventional manufacturing procedures, 3D printing offers the possibility, almost without limitations, to generate realistic and patient- specific objects. Depending on the imaging technique, the material must have specific physical properties to make these objects suitable for use as medical phantoms. For this purpose, defined quantities of nanoparticles can be added to the 3D printing material before processing.

The challenges in producing such nanocomposites, however, are high, especially with regard to the uniform distribution of the nanoparticles. PTB has developed a system for the reproducible synthesis of resin-based nanocomposites. Known as the Continuous Energetic Liquid Agitation System, or ConELiA, it guarantees a defined and reproducible adjustment of the desired material composition. Homogenization takes place in a special ultrasonic flow cell, while additional sensors allow direct monitoring of the process during fabrication. The novel system (patent pending) can be used independently or in connection with resin-based 3D printing systems and will be made available to a large user base via the B-smart Lab (Berlin Scientific Manufacturing for Research and Technology Laboratory).

As part of a technology transfer project, the procedure has already been used to fabricate long-term stable homogeneous specimens from magnetic reference materials. These specimens are of great importance for the development of applications in magnetic particle imaging and for the harmonization of magnetic measuring techniques. Furthermore, this new process technology will enable the fabrication of tissue-equivalent phantoms for fluorescence imaging.


Norbert Löwa
Department 8.2, Biosignals
Phone: +49 30 3481-7736

Scientific publication

N. Löwa, R. Hoffmann, D. Gutkelch, O. Kosch, S. Dutz, F. Wiekhorst: A multi-purpose phantom kit for magnetic particle imaging. Current Directions in Biomedical Engineering 7, 319–322 (2021)