220 likes | 233 Views
Optimization of the production and insertion of 3-dimensional polyimide electrodes into rats. Lab of Professor Patrick Rousche Hananeh Esmailbeigi Daniela Aizpitarte. Overall Picture. Create a 3d electrode Will be filled with neurotrophic factors to increase neuron growth in the region
E N D
Optimization of the production and insertion of 3-dimensional polyimide electrodes into rats Lab of Professor Patrick Rousche Hananeh Esmailbeigi Daniela Aizpitarte
Overall Picture • Create a 3d electrode • Will be filled with neurotrophic factors to increase neuron growth in the region • Goal is to decrease noise and measure strong long term signals • Has many uses for neural prosthetics • Made of polyimide-a very flexible polymer
1st Project: Creating a rolling system • Current system is time consuming • Requirements: • Steady the two needles • Keep the electrode perpendicular to the needle • Be able to roll electrodes quickly • Allow the needles to be removed after use Image from www.sanimedtech.com
2nd Project: Implantation • A hypodermic needle needs to accompany the electrode • Rolled tip is too blunt to penetrate the pia without buckling • Needs to be simple to make • Can’t increase damage to the surrounding tissue
Injection Needle Idea • How it works: • The two halves are gently separated • One half is pulled up at a time • Made of stainless steel • Advantages: • Simple construction • Disadvantages: • Hard to control
Final Inserter Design Glass capillary tube 4mm long Tip sanded down to a 45 degree angle Success when used in surgery
Force of Implantation • A glass capillary tube at a 45 degree angle was sanded down and inserted 4mm into 0.5% agar gel • Three different relatives speeds were tested: fast, medium, slow • Fast= 5-7mm/s • Medium=2.5-3.5mm/s • Slow=0.3-0.5mm/s
Conclusions Inserting faster exerts less force (speed dependent) Diameter had to be taken into account Steel and glass are of the same hardness, and should exert the same force Per surface area of 1.2mm diameter circle
Conclusions Water is easily lifted up the electrode and gives varying measurements Force changes on the order of 0.01 mN Too small to have great significance
Conclusion The effect of water on the electrode is minimal The electrode prefers the agar over glass capillary tube Reason why the surgery worked Actually pulls away the agar gel Electrode rolling technique overall didn’t work better than hand rolling
Acknowledgments I would like to thank the financial support from the EEC-NSF Grant # 0755115 for funding the REU program. Also, I would like to thank Professor Rousche and the rest of the REU program for giving me this project.