This is the third in a series of posts about a BioPrinter project I’ve been working on. To read the previous two posts about my experiences before and after the Boston Science Hack Day 2015 see: https://scienceroastery.wordpress.com/2015/01/26/the-bioprinter-at-boston-science-hack-day-2015-part-2/ and https://scienceroastery.wordpress.com/2015/01/06/the-bioprinter-at-boston-science-hack-day-2015/
Last week I had the opportunity to test out out the BioPrinter with some live cells! I was impressed at how easily the whole process went. I unpacked the printer–it survived the trip back from Boston surprisingly well–and tested it with a few practice images. Surprisingly, the most difficult part of this step was disassembling the ink head and removing the ink. The plastic is pretty hard and doesn’t like to be opened with a box cutter. However, once the ink was rinsed out with some distilled water, I was able to put in ~2mL of cell culture and print them onto a plate without difficulty!
I was happy that the grids of cells from the first run came out as a series of discrete dots albeit in lines that are slightly askew. The uneveness of the lines is mostly due to the momentum generated by the movement of inkhead and petri dish during the print process. Down the road we’re interested in using this printer to dispense cells into 384 well plates for culturing experiments, and the fact that the printer produced individual spots suggests that we will be able to use the printer to “load” those plates.
This version of the printer is mostly a proof-of-concept. As you can see, there is some splatter on the plates due to the height of the inkjet. We’re limited in this respect because of the holes I originally drilled into the frame holding up the top motor/inkhead assembly. The lowercase letters are also a little difficult to read, so we might stick to capitals for a while. I’ll also want to eventually increase the print area. The CD drive heads limits us to about a 100×100 pixel print area which is a little less than 1.5 x 1.5 in. Replacing these with motors similar to those used in various RepRap projects would give us a substantially larger print area.
My next attempt will be to print a gradient of cells and/or nutrients on the plate. The nutrient gradient might pose a bit of a problem because any nutrient solution we dispense on the plate is likely to diffuse through the agar, but we won’t know to what extent this will be an issue unless we try!
If you are interested in the code used to run the printer, please take a look at these two GitHub repos and email me if you have any questions. I would be happy to walk anyone through the code:
Before you go, here’s a video of the printer in action!