3D Bio Printing & Biofabrication

This week we mixed bacteria into a Pluronic gel and 3D printed with it.

Vocabulary:

Pluronic: a water soluble, thermal reversible substance. It solidifies at warmer tempertures, and melts at cooler temperatures. This powder is mixed with PBS (a classical chemical used in cell culture)

Slicer: the software used to deconstruct a 3D file type, in this case an STL, into layered g-code for 3D printing.

REFERENCE: Multivascular networks and functional intravascular topologies within biocompatible hydrogels, Science 03 May 2019

Lab notes:

The first part of the lab was mixing and testing the gel. This was challenging because the gell froze at ambient temperatures, so we had to work quickly to keep it cold enough and liquid enough to mix with the bacteria. Even so the gell clogged the pippet and I needed to put it back in the fridge to allow it to cool down and re-liqify.

After the samples were mixed we tested the gels consistency by hand pipetting it to see if it was solid enough to allow layer stack up, if it was too liquid the layers would flow together.

We imported STLs into Simplify 3D and treated this like a normal 3D printing process, but with much bigger layer height than usual. The figure on the left shows the machine. The extruder is just a syringe, where we put the bateria gel. The right shows the computer with the slicer sending the CNC data.

Below shows some of the settings we adjusted in the slicer. The middle figure is the sclicers rendering of what should print, and the figure below on the right is what actually printed.