Mixing and Injection System for Polyurethane Scaffolds

Michael SchererDustin DowellAndrew Solomon

January 17th, 2007

Background

Indicated for:– Small bone fractures (i.e. distal radius fracture)– Bone cancer repairs (void filler)– Antibiotic delivery– Growth hormone delivery

Operating room materials:– Two pre-packaged components (hardener + isocyanate)– Mixing device– Syringe

Procedure

In the OR, the polymer is stored as two separate components

When needed, both elements will be added to the container.

The container will then be inserted into the mixing fixture.

Procedure

After mixing is complete, the container is removed from the fixture. (Mixing time TBD)

Ideally, for injection, an attachment will be employed to move the mixture into an injection device.

Once attached, the mixture would be forced out of the container by pushing the moveable container bottom.

5-10 minute working time depending on composition

Current Budget Estimate

Item Cost Dremel $75 (known)Agitator $150 (estimate)Canister $50 (est.)Device Housing $50 (est.)Miscellaneous Fixtures $50 (est.)

TOTAL: $375 Notes:

– Agitator requires special manufacturing– All estimates are conservative

Current Work

Fabricating an agitator; finalize design

Waiting on supplies– Dremel tool– Canister

Trying to get in touch with Dr. Papay– Specific applications– Volumes

http://www.postmixing.com/mixing%20forum/images/rt6.jpg

Future Work

Experimental testing– What speed to mix (5,000 – 15,000 RPMs)– How much mixing time is needed (30 - 90 s)– Optimal agitator design– Achieve necessary physical properties

Develop a system for transferring mixture from canister to syringe