Implantable probe with split anchors via residual stress and induced cell growth with gelatin nanofibres
Journal
Micro and Nano Letters
Journal Volume
9
Journal Issue
12
Pages
901-905
Date Issued
2014
Author(s)
Abstract
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.
Type
journal article