Bioengineering researchers at Rice University (Houston, TX) have modified a commercial-grade carbon dioxide (CO2) laser cutter to create OpenSLS, an open-source, selective laser-sintering (SLS) platform that can print intricate 3D objects from powdered plastics and biomaterials. The system costs at least 40 times less than its commercial counterparts, and allows researchers to work with their own specialized powdered materials. OpenSLS, which was built using low-cost, open-source microcontrollers, cost less than $10,000 to build—commercial SLS platforms typically start around $400,000 and can cost up to $1 million.
The team showed that the machine could print a series of intricate objects from both nylon powder and from polycaprolactone (PCL), a nontoxic polymer commonly used to make templates for studies on engineered bone. In a post-sintering step, the rough surfaces of PCL objects that come out of the printer are exposed to solvent vapor for short time periods (around 5 minutes), resulting in a very smooth surface because of surface-tension effects. In tests using human bone marrow stromal cells (the type of adult stem cells that can differentiate to form bone, skin, blood vessels, and other tissues), the vapor-smoothed PCL structures worked well as templates for engineered tissues that have some of the same properties as natural bone. All the hardware designs and software modifications for the SLS platform are open-sourced and shared via Github. Reference: I. S. Kinstlinger et al., PLoS ONE (2016); http://dx.doi.org/10.1371/journal.pone.0147399.