A bipolar electrode probe used for implantable nerve stimulation treatments in minimally invasive surgeries is presented. The probe is composed of a flexible printed circuit substrate and a patterned SU-8 film. This probe features a three-dimensional (3D) tweezer-like mechanism opened by residual stress from the SU-8 film, designed to fix the probe in the tissue surrounding a target nerve. Stripes on the SU-8 film direct the net residual stress in a single direction to form a curve. The holding strengths of the probes with different deformations are defined and measured by a tensile test. Results show that the fixing ability of a 3D probe is better than a plane probe. The probes with curvature heights between 13 and 14 mm have a maximum average breaking force of 0.258 N, which is 16.3 and 13.1% higher than the probes with curvature heights between 9 and 10 mm and between 10 and 11 mm, respectively. In addition, a film of gelatin fibrous membrane, produced by electrospinning, covers the fixed ends of the probe's anchors and acts as cell scaffolds to induce cell growth, which help to ensure long-term fixation in the body. 3T3 fibroblast cells are grown to verify the scaffold effect of the fibrous membrane.

References

1. 1)
  - 4. Geurts, J.W.M., Lou, L., Gauci, C.A., Newnham, P., Van Wijk, R.M.A.W.: ‘Radiofrequency treatments in low back pain’, Pain Pract., 2002, 2, pp. 226–234 (doi: 10.1046/j.1533-2500.2002.02028.x).
2. 2)
  - 3. Fuentes, R., Petersson, P., Siesser, W.B., Caron, M.G., Nicolelis, M.A.: ‘Spinal cord stimulation restores locomotion in animal models of Parkinson's disease’, Science, 2009, 323, pp. 1578–1582 (doi: 10.1126/science.1164901).
3. 3)
  - 18. Liu, C.L., Tang, D.P.: ‘Effect of diamond film's thickness on thermal residual stress after considering the substrate's plasticity’, Adv. Mater. Res., 2011, 154, pp. 1199–1202.
4. 4)
  - 11. Karande, T.S., Ong, J.L., Agrawal, C.M.: ‘Diffusion in musculoskeletal tissue engineering scaffolds: design issues related to porosity, permeability, architecture, and nutrient mixing’, Ann. Biomed. Eng., 2004, 32, pp. 1728–1743 (doi: 10.1007/s10439-004-7825-2).
5. 5)
  - 10. Mahdavi, A., Ferreira, L., Sundback, C., et al: ‘A biodegradable and biocompatible gecko-inspired tissue adhesive’, Proc. Natl. Acad. Sci. USA, 2008, 105, pp. 2307–2312 (doi: 10.1073/pnas.0712117105).
6. 6)
  - 7. Shepherd, R.K., Hatsushika, S., Clark, G.M.: ‘Electrical stimulation of the auditory nerve: the effect of electrode position on neural excitation’, Hear. Res., 1993, 66, pp. 108–120 (doi: 10.1016/0378-5955(93)90265-3).
7. 7)
  - J.M. Deitzel , J. Kleinmeyer , D. Harris , N.C. Beck Tan . The effect of processing variables on the morphology of electrospun nanofibres and textiles. Polymer
8. 8)
  - 6. Tendick, F., Sastry, S.S., Fearing, R.S., Cohn, M.: ‘Applications of micromechatronics in minimally invasive surgery’, IEEE/ASME Trans. Mech., 1998, 3, pp. 34–42 (doi: 10.1109/3516.662866).
9. 9)
  - 13. Zhong, Y., Yu, X., Gilbert, R., Bellamkonda, R.V.: ‘Stabilizing electrode-host interfaces: a tissue engineering approach’, J. Rehabil. Res. Dev., 2001, 36, pp. 627–932.
10. 10)
  - 17. Hui, C.Y., Conway, H.D., Lin, Y.Y.: ‘A reexamination of residual stresses in thin films and of the validity of Stoney's estimate’, J. Electron. Packag., 2000, 122, pp. 267–273 (doi: 10.1115/1.1287930).
11. 11)
  - 9. Bjarkam, C.R., Jorgensen, R.L., Jensen, K.N., Sunde, N.A., Sørensen, J.C.H.: ‘Deep brain stimulation electrode anchoring using BioGlue (R), a protective electrode covering, and a titanium microplate’, J. Neurosci. Methods, 2008, 168, pp. 151–155 (doi: 10.1016/j.jneumeth.2007.09.008).
12. 12)
  - G. Voskerician , M.S. Shive , R.S. Shawgo , H.V. Recum , J.M. Anderson , M.J. Cima , R. Langer . Biocompatibility and biofouling of MEMS drug delivery devices. Biomaterials , 11 , 1959 - 1967
13. 13)
  - 12. Geddes, L.A., Roeder, R.: ‘Criteria for the selection of materials for implanted electrodes’, Ann. Biomed. Eng., 2003, 31, pp. 879–890 (doi: 10.1114/1.1581292).
14. 14)
  - 16. Wu, S.C., Chang, W.H., Dong, G.C., Chen, K.Y., Chen, Y.S., Yao, C.H.: ‘Cell adhesion and proliferation enhancement by gelatin nanofiber scaffolds’, J. Bioact. Compat. Polym., 2011, 26, pp. 565–577 (doi: 10.1177/0883911511423563).
15. 15)
  - 2. Cahana, A., Van Zundert, J., Macrea, L., Van Kleef, M., Sluijter, M.: ‘Pulsed radiofrequency: current clinical and biological literature available’, Pain Med., 2006, 7, pp. 411–423 (doi: 10.1111/j.1526-4637.2006.00148.x).
16. 16)
  - 5. Byrd, D., Mackey, S.: ‘Pulsed radiofrequency for chronic pain’, Curr. Pain Headache Rep., 2008, 12, pp. 37–41 (doi: 10.1007/s11916-008-0008-3).
17. 17)
  - 8. Favre, J., Taha, J.M., Steel, T., Burchiel, K.J.: ‘Anchoring of deep brain stimulation electrodes using a microplate: technical note’, J. Neurosurg., 1996, 85, pp. 1181–1183 (doi: 10.3171/jns.1996.85.6.1181).
18. 18)
  - 1. Tehovnik, E.J.: ‘Electrical stimulation of neural tissue to evoke behavioral responses’, J. Neurosci. Methods, 1996, 65, pp. 1–17 (doi: 10.1016/0165-0270(95)00131-X).

Implantable probe with split anchors via residual stress and induced cell growth with gelatin nanofibres

References

Related content