Gel Printing, bioprinting, food printing on the um... any advice?

[jemma-redmond 0]

Hullo again!

So I've been modifying um's to extrude all sorts of viscous liquids... My background is in nanobioscience and I've done stuff like print finger bones (regular pla) and seeded them with osteoblasts (bone cells) and yes they grow well... anyways, I have also printed dicom (mri) data using a um into liquid, like arteries, reproductive, carcinoma's, etc etc it was just proof of principle.

So I was wondering what experience you have had printing bio goop yourselves? What kind of mechanisms were you using? We used something based on organovo;s and also integrated the diybio bioprinter inkshield dealie into a um hybrid and it worked not so bad I would say.

Has anyone integrated any pump systems into the printer? heating coils to control the viscosity etc? What needles did you use and how low could you go?

I found the triangular plastic nozzles worked way better than the metal needles for example..

Thanx!

Jem

 

[anon4321 16]

Sorry, I'm a computer geek but I just need to say

COOL!

 

[tmrevlje 1]

Yea this is a very cool topic, kudos to you Jemma. I am currently on a short project where we're using MRI, CT and OCT scan 3D data to print out various structures of the human body, we have plans for the future to go into a more human body friendly printing. I see you're already on it looking very much forward to your future updates and posts.

 

[jhertzberg 19]

What software are you using to convert DICOM CT files to STL? I have tried invesalius and 3DSlicer, but I'm still having to do a lot of cleanup to get manifold models.

 

[anon4321 16]

Saw this and thought you might be interested -

LionShark

http://www.thingiverse.com/thing:412197

wait what ?!?!....

No this is it -

Peristaltic Pump

http://www.thingiverse.com/thing:412150

Wonder if you could drive it with a stepper for precise dispensing.

 

[jemma-redmond 0]

Hello!!

Ok with regards to converting dicom to stl, I cheated, as it was like too much effort. So I found online a japanese mri database, its been translated into english and has a complete human body up there as dicom files converted to stl's so I used that as a proof of concept. I don't have a direct link, you will have to do a search but its there, somewhere's...

As for the pump, I made a few of these, I'm not convinced by these, I have medical grade dealies here for dispensing fluids, they work well but the pumps you can print? With pla its way too unreliable, too much friction, too much heat, I would imagine the abs would not be much better sue to warping. I think you would have to get the parts sintered and even then I would probably avoid using polymers, stainless steel seems to be the way to go. As for precision, I am doubtful... I feel there will be a lag between extrusion and the pump activating which will mess up the build but i have yet to really try this.

 

[anon4321 16]

If what you are pumping is hot, ABS might be better or I would recommend Colorfabb XT which is similar to ABS but easier to print.

Take a look at that pump design. All the friction points are on bearings and it even uses bearings to compress the tube

I think the precision of the printed parts would be good enough for this. As far as pumping precise amounts, that would depend on the length of tube to the head and it's elasticity and the pump's pressure and leakage back through it.

Not sure about your comments on stainless and sintered parts as nothing but the tube comes in contact with what is being pumped.

Certainly, you understand what it is needed for but might be worth a try.

 

[jhertzberg 19]

For discrete small prints, I would think that any number of the head mounted http://www.thingiverse.com/search/page:1?q=syringe+extruder&sa= would be the way to go. For larger prints or a more continuous process, perhaps a head mounted http://www.thingiverse.com/search/page:1?q=moineau&sa= would be better.

Regarding other peoples MRIs, I found that the http://3dprint.nih.gov/ is great, but I am trying to print the CT of my own tib/fib spiral fracture as a thank you gift for my surgeon.

 

[jemma-redmond 0]

yep, there are many methods... s[pray printing, syringe extrusion, pump extrusion etc etc thanks for the link, that is useful, I have shared it with the diybio group... you might find that useful to join, you may get some more info there...

:-P

 

[jhertzberg 19]

Thanks, that's an interesting group.

 

[cez_etc 0]

I've never printed bio-goop but I've worked on microfluidic projects where we continuously pumped very small amounts of fluids (that whole lab-on-a-chip thing).

From that experience: Nothing comes even close to the precision of glass syringes. And they are much easier to clean than the plastic ones. They are expensive but worth every penny unless one of the lab members is extremely clumsy and keeps dropping them. Not that this ever happened :-P

We also used high-precision pumps with a RS232 interface that had very little delay. The pumps were controlled by a LabView program which also recorded various sensor data.

Anyway, really interested to read more about your research!

 

[tmrevlje 1]

What software are you using to convert DICOM CT files to STL? I have tried invesalius and 3DSlicer, but I'm still having to do a lot of cleanup to get manifold models.

 

Hi jhertzberg,

we are using 3MENSIO programme - http://www.3mensio.com/ that has a module for exporting DICOM files to STL. It is sadly not free software and the export isn't that easy either.

I have spoken to a guy on thingieverse who did an DICOM - STL conversion fairly good and he said he uses Invesalius that you also mentioned. I personally have not gotten to explore that particular piece of software yet, but I plan to. OsiriX (Mac only) is suppose to do a good job too, but is not that easy to use (so I've heard).

The STL database (japanese) that Jemma is mentioning you can find here:

http://lifesciencedb.jp/bp3d/

It's a good site, with many body parts made into STL files. Not all of them though

Enjoy

 

[jhertzberg 19]

Thanks. I looked at the OsiriX manuals table of contents online, but I don't see where it exports to STL. Is it through a plug-in?

 

[jemma-redmond 0]

Yeah, the biology people have a mac with osirix on it... but we didn't have much luck doing dicom to stl conversions.. I've used other software but the tutorials are cryptic to say the least. I shall have to ask around and see if anyone knows any better software packages....