The use of animal models is a widespread practice in university and industrial biomedical research for observing research results, for example from conventional 2D cell culture, in the context of an entire organism. The data generated in animal models are often seen to be an essential first step for transferring the results to humans, however, no transferability can be guaranteed due to species-specific differences. [1, 2]
The 3R principle
In addition, ethical concerns about animal testing are increasingly becoming the focus of researchers and the general public, but also of legislators. In 1959, the 3R principle for responsible animal testing was formulated with the goal of avoiding its use in scientific research, reducing the number of animals used and thus keeping animal suffering as low as possible (replacement, reduction, refinement). 
3D cell culture as a contribution to responsible animal testing
To be able to simultaneously generate physiological and species-relevant results while reducing the scope of animal testing, three-dimensional cell culture (3D cell culture) has been established in recent years in many laboratories around the world as a reliable, future-oriented and, compared to animal testing, low-cost cell culture technique.
Spheroid and organoid cultures simulate the in vivo situation
Through the formation of three-dimensional structures in model systems such as spheroid or organoid cultures, pronounced cell-cell contacts and cell-matrix contacts similar to those in comparable tissue in vivo can be established.  This means that the morphology and behaviour of cells that are cultivated in 3D structures are more similar, for example at the gene expression level, to the in vivo state than cells in 2D cell cultures – they mimic the in vivo microenvironment. 
Models of the 3D cell culture allow patient-based studies, e.g. in medication research
Even multi-organ systems can be replicated in vitro using a 3D cell culture approach.  This large number of technical options of varying levels of complexity offers promising approaches going beyond basic research in drug development and personalised medicine. This allows physiologically meaningful toxicity testing of new molecules to be carried out in drug development and directly on human cells without having to perform a large number of animal experiments. In addition, screening for suitable drugs is made easier by 3D cell culture and more targeted research can then be conducted with promising candidates.  For example, the patient's own cells can be used to create 3D models in order to test the efficacy of available treatment options in advance and to be able to give the patient the most promising treatment right from the start. 
BIOFLOAT™ enables reliable spheroid formation for reproducible results
But although a variety of cell models have already been described and are in use around the world, 3D cell culture is still in the starting blocks in many places. To support scientists in their effort to reduce animal testing and help them reach new insights, SARSTEDT offers BIOFLOAT™ for reliable quality and, along with our many years of experience in cell culture, comprehensive support for successful growth results.
 Bell, Catherine C, Anita C A Dankers, Volker M Lauschke, Rowena Sison-Young, Roz Jenkins, Cliff Rowe, Chris E Goldring, Kevin Park, Sophie L Regan, Tracy Walker, Chris Schofield, Audrey Baze, Alison J Foster, Dominic P Williams, Amy W M van de Ven, Frank Jacobs, Jos van Houdt, Tuula Lähteenmäki, Jan Snoeys, Satu Juhila, Lysiane Richert, and Magnus Ingelman-Sundberg. "Comparison of Hepatic 2D Sandwich Cultures and 3D Spheroids for Long-term Toxicity Applications: A Multicenter Study." Toxicological Sciences 162.2 (2018): 655-666.
 Imamura, Yoshinori, Toru Mukohara, Yohei Shimono, Yohei Funakoshi, Naoko Chayahara, Masanori Toyoda, Naomi Kiyota, Shintaro Takao, Seishi Kono, Tetsuya Nakatsura, and Hironobu Minami. "Comparison of 2D- and 3D-culture models as drug-testing platforms in breast cancer." Oncology Reports 33.4 (2015): 1837-1843.
 Curzer, Howard, Gad Perry, Mark Wallace, and Dan Perry. "The Three Rs of Animal Research: What they Mean for the Institutional Animal Care and Use Committee and Why." Science and Engineering Ethics 22.2 (2015): 549-565.
 Huh, D., G. A. Hamilton, and D. E. Ingber. "Program, B. From Three-Dimensional Cell Culture to Organs-on-Chips." Trends Cell Biol 21 (2011): 745-754.
 Bédard, Patrick, Sara Gauvin, Karel Ferland, Christophe Caneparo, Ève Pellerin, Stéphane Chabaud, and Stéphane Bolduc. "Innovative Human Three-Dimensional Tissue-Engineered Models as an Alternative to Animal Testing." Bioengineering 7.3 (2020).
 Suarez-Martinez, Elisa, Irene Suazo-Sanchez, Manuel Celis-Romero, and Amancio Carnero. "3D and organoid culture in research: physiology, hereditary genetic diseases and cancer." Cell & Bioscience 12.1 (2022).
 Barbosa, Mélanie A. G., Cristina P. R. Xavier, Rúben F. Pereira, Vilma Petrikaitė, and M. Helena Vasconcelos. "3D Cell Culture Models as Recapitulators of the Tumor Microenvironment for the Screening of Anti-Cancer Drugs." Cancers 14.1 (2021).