Chemically defined formation of spheroids loaded with superparamagnetic iron oxide nanoparticles

J. Wiest1*, E. Stetter2, M. Koch3

ALTEX Proceedings, 2021, 9, 1, 217

1 cellasys GmbH, Kronburg / Germany,
2 Stetter Elektronik, Seeheim-Jugenheim / Germany,
3 Feldkraft Ltd., Copenhagen / Denmark

Corresponding author: J. Wiest,

To increase physiological relevance and to develop new therapies 3D spheroids are of increasing interest. The addition of superparamagnetic iron oxide nanoparticles (SPIONs) into the spheroid allows for investigation of new therapeutic strategies (Zhang et al., 2014) without the use of animals (Lei and Schaffer, 2013; Whatley et al., 2014; Marx et al., 2016). L929 fibroblasts were maintained in 25 mL Greiner Bio-One AdvancedTC© cell culture flasks in chemically defined DME/F12+ITS cell culture medium. Cells received fresh medium twice a week and were passaged at about 80% confluency once a week. Spheroids were created similar to a previously developed method (Alexander, Eggert and Wiest, 2018). The 20 nm SPIONs beads were obtained from micromod Partikeltechnologie GmbH (Rostock / Germany) and a stock solution with 100 µg/mL was prepared. Spheroids were prepared in a 96 well-plate with cell-repellent surface (Greiner Bio-One GmbH, #650970). Each well was filled with 190 µL DME/F12+ITS containing 10.000 L929. For the SPION loaded spheroids (SPION-LS), 10 µL of magnetic beads stock solution was added, whereas for the non-magnetic control spheroids (NM-CS) 10 µL of cell culture medium was added. Then the 96well plate was centrifuged at 1000 g for 5 min and finally incubated at 37°C with 5% CO2. 100 µL of medium in each well was replace by fresh DME/F12+ITS (preheated to 37°C) daily. Spheroids were used for the experiments on day 5. For manipulation of the spheroids a neodym magnet (length 25 mm, diameter 25 mm) was used in a distance of approximately 30mm. The calculated field force acting on the spheroids was approximately 30mT. To investigate if the SPIONs are incorporated into the spheroids one SPION-LC was transferred to a well with one NM-CS. The movement of the SPION-LC due to the applied magnetic field can be seen at .

Alexander, F., Eggert, S. and Wiest, J. (2018) ‘A novel lab-on-a-chip platform for spheroid metabolism monitoring’, Cytotechnology. Springer Netherlands, 70(1), pp. 375–386. doi: 10.1007/s10616-017-0152-x.

Lei, Y. and Schaffer, D. V. (2013) ‘A fully defined and scalable 3D culture system for human pluripotent stem cell expansion and differentiation’, Proceedings of the National Academy of Sciences of the United States of America, 110(52). doi: 10.1073/pnas.1309408110.

Marx, U. et al. (2016) ‘Biology-inspired microphysiological system approaches to solve the prediction dilemma of substance testing’, Altex, 33(3), pp. 272–321. doi: 10.145/3/aitex.1603161.

Whatley, B. R. et al. (2014) ‘Magnetic-directed patterning of cell spheroids’, Journal of Biomedical Materials Research – Part A, 102(5), pp. 1537–1547. doi: 10.1002/jbm.a.34797.

Zhang, E. et al. (2014) ‘Dynamic Magnetic Fields Remote-Control Apoptosis via Nanoparticle Rotation’, ACS Nano. American Chemical Society, 8(4), pp. 3192–3201. doi: 10.1021/nn406302j.

5th German Pharm-Tox Summit

Cell line authentication

For biocompatibility assays and the cellasys #8 protocol we use the L929 cell line. As a prerequisition for reliability of data, our cell line was recently analysed by the Leibniz-Institut DSMZ-Deutsche Sammlung von Mikroorganismen und Zellkulturen GmbH.

Please find the species identification in our quality management section.


cellasys, Technische Universität München and MatTek In Vitro Life Science Laboratories present recent updates about our “Tissue-on-a-Chip” at the 22nd European Congress on Alternatives to Animal Testing:


In this study we demonstrate a microphysiometric system based on IMOLA‑IVD device that will allow real-time measurement of multiple parameters in human small intestine tissue model (EpiIntestinalTM). The parameters are measured non-invasively, while the system provides fresh nutrients and allows programmable repeated dosing of test articles. In the presented set of experiments we have concentrated on trans-epithelial electric resistance (TEER) as this parameter was previously established to reflect an integrity of EpiIntestinal tissue model. The performance of the system was verified and baselines were established by long term incubation of EpiIntestinal tissue in IMOLA-IVD, followed by single application of 2% SDS.

Animal Experimentation: Working Towards a Paradigm Change

Workshop und deutsche Buchpremiere am 14. und 15. Juni in München

Tierversuche zählen zu den umstrittensten Praktiken, in denen wir Tiere nutzen, insbesondere weil den Tieren hier absichtlich Schmerzen, Leiden und Schäden zugefügt werden – mit der Begründung eines möglichen Erkenntnisgewinns für den Menschen. An dieser Rechtfertigung für die Unerlässlichkeit von Tierversuchen hat sich wenig geändert, und das, obwohl nicht nur die ethischen Probleme, sondern auch die wissenschaftlichen Mängel von Tierversuchen mittlerweile offensichtlich und gut dokumentiert sind. Dieses Wissen über die Probleme im Zusammenhang mit Tierversuchen ist allerdings noch nicht weit verbreitet, und es besteht die Gefahr, dass es schlicht ignoriert wird.

Der Flyer findet sich hier.

Cells and tissue as prediction model at EMBC 2019

The combination of classical engineering disciplines and knowledge from cell biology allows the construction of physiologically relevant models to predict processes in the human body in-vitro. In the symposium different aspects of tissue-on-a-chip systems are presented. These include a biopsy-based approach to develop personalized therapies for cancer patients. A bone-on-a-chip that allows the investigation of 3D bone organoids under mechanical load and it’s optimization using in-silico technologies. Further, the necessity of including immune cells into models of osteochondral tissues will be discussed. Examples about applications of dynamic magnetic fields to improve transfection and apply mechanical force inside living cells, a case study about a tissue-on-a-chip system for skin and intestine for applications in toxicology and aspects to employ living cells as biosensors in microphysiometrical systems are on the agenda.

At IEEE EMBC 2019 in Berlin / Germany cellasys co-organizes a symposia on:

Cells and tissue as prediction model for toxicology, drug development and personalized medicine ( organized by J. Wiest and F. Schulze )

M. Brischwein: Development of personalized therapies for cancer with 3D tumor spheroids

Multicellular tumor spheroids are 3D models generated from various cell types, including heterogeneous tissues of solid human tumors. They have proven utility for predictive testing of patient samples to identify the most promising pharmaceutical anti-cancer treatment.

F. Schulze: Mechanical loading of human osteoblasts in a bone-on-a-chip

Organ-on-chip systems are used to recreate the physiology of a certain tissue or organ of interest, thereby enabling more detailed investigations than conventional cell culture allows for. In this project a bone-on-a-chip system is presented that allows for control of oxygen levels and mechanical loading

A. Lang: Modelling the crosstalk between immune cells and bone

Interaction between immune cells and bone metabolism plays a crucial role in the pathogenesis of several disorders affecting the musculoskeletal system. However, current engineering approaches exclude the immune system due to its complexity. Here, we aim to present the importance of modelling the crosstalk between immune cells and bone as exemplified by mimicking the initial phase of fracture healing in vitro.

M. Koch: New magnetic field device for application with laser microscopes

A new digitally controlled field generator is integrated into a laser microscope. Magnetic particles powered non-invasively by the field generator treat cell populations inside a dish above the microscope lens, which can be observed in real time.

J. Wiest: Tissue-on-a-chip

Microphysiometry is a powerful tool to monitor the energy metabolism and changes in morphology of living cells. Until now, the technique was mainly used for monitoring of cells in 2D monolayers. Now, the cellasys group showed that it is possible to monitor the extracellular acidification rate (EAR) and transepithelial electrical resistance (TEER) of 3D skin constructs in an automated assay maintaining an air liquid interface (ALI) with the IMOLA-IVD technology.

2018 Annual Meeting of the Chinese Society of Biochemistry and Molecular Biology

The 2018 Annual Meeting of the Chinese Society of Biochemistry and Molecular Biology will take place from 25 – 28 October 2018 in Chongqing / China. Please visit our distribution partner Quantum Desing China in the exhibition.

The Lush Prize Conference 2018

Meet us at The Lush Prize Conference 2018.

Welcome to Berlin for The Lush Prize Conference 2018: Is there an end in sight for animal testing? Can Organ-on-a-Chip replace animal use in safety testing with advanced human focused approaches?

7th International Yeast 2.0 and Synthetic Genomes Conference

The 7th International Yeast 2.0 and Synthetic Genomes Conference will take place from 26 – 28 November 2018 in Sydney / Australia. Please visit our distribution partner Cell Systems Biology in the exhibition.

12th Annual BioProcessing Network Conference

The 12th Annual BioProcessing Network Conference will take place in Melbourne / Australia. Please visit our distribution partner Cell Systems Biology in the exhibition.

The meeting gathers together researchers, manufacturers, suppliers and others with an active interest in bioprocessing as applied to a broad range of industrial and academic research areas. Informative presentations and the opportunity to network and discuss new data, concepts and emerging trends in an informal environment is a feature of the conference.