Serotonin structure, the 3D coordinate is from PubChem https://pubchem.ncbi.nlm.nih.gov/compound/serotonin, converted to PDB format using http://pasilla.health.unm.edu/tomcat/biocomp/convert.
The PDB is used here to get the 3D STL file.

The model is printed using Ultimaker3 with special support material. We used Polysupport from Polymaker.