UCL researchers discover limitation in 3D printing pills
It turns out some drugs can't be 3D printed

This month, we’re honing in on the intersecting medical and additive manufacturing industries. Primarily, we’re looking at how AM applications in the medical sector are providing new opportunities and benefits for patient care, but it is also important to look at the limitations that still exist with 3D printing in healthcare. An interesting bit of research coming out of University College London highlights these limitations perfectly in the area of 3D printed medication.
Researchers at University College London have played a pivotal role in the development of 3D printed pills. Specifically, Simon Gaisford, a Professor of Pharmaceuticals, has led innovative research in the use of SLA 3D printing for producing pills with custom doses. This research, as some will know, resulted in the formation of a spin-off company dedicated to printing medication, FabRx.
FabRx’s work has proven that SLA 3D printing is viable for printing polypills with up to six different kinds of drugs, each of which is mixed in with a consumable light-curing resin. Up until recently, the method showed nothing but promise, with drugs like ibuprofen, paracetamol, caffeine and naproxen being successfully printed and tested.
Now, however, the researchers have found that some drugs are not compatible with the SLA-based 3D printing process and light-curing resins.
The discovery came to light when Gaisford and his team were printing pills made up of four types of drugs for treating high blood pressure. Once the polypill was printed, the research team tested its efficacy. To their surprise, they found that one drug—amlodipine—had not been released.
Upon further inspection, the research team was able to eliminate a range of possibilities for the missing drug, including low levels of amlodipine, the drug being trapped in the polymer matrix and problems with detection. Ultimately, they realized the trouble was caused by a reaction between the drug and the photoreactive monomers. This led the FabRx team to understand that not all drugs would be 3D printable using its existing process and resin materials.
Discovering the limitation is not bad news. It will actually enable the research team to come up with a more reliable solution for producing polypills in the future, or at the very least understand what types of drugs can not be 3D printed.
In addition to working with SLA, FabRx has pioneered FDM and SLS processes for printing different types of medication. The company is expected to bring to market a bespoke pharmaceutical 3D printer—the Medimaker) this year.