Flexible Neural Interfaces based on Graphene–PAN Composite for the Treatment of Constipation via Sacral Nerve Stimulation

Hejazi, Maryam Alsadat; Jahangiri, Mohammad Mehdi; Gorgi, Khadijeh; Koohi-Hosseinabadi, Omid; Seyedi, Seyed Amir; Mirzaei, Esmaeil; Rouzegar, Jafar; Mehdizadeh, Alireza

doi:10.31661/jbpe.v0i0.2508-1976

Flexible Neural Interfaces based on Graphene–PAN Composite for the Treatment of Constipation via Sacral Nerve Stimulation

Document Type : Original Research

Authors

Maryam Alsadat Hejazi ¹^{, 2}

Mohammad Mehdi Jahangiri ³

Khadijeh Gorgi ⁴

Omid Koohi-Hosseinabadi ⁵

Seyed Amir Seyedi ⁶

Esmaeil Mirzaei ⁷

Jafar Rouzegar ⁸

Alireza Mehdizadeh ²

¹ Department of Medical Physics and Engineering, School of Medicine, Shiraz University of Medical Sciences, Shiraz, Iran

² Research Center for Neuromodulation and Pain, Shiraz University of Medical Sciences, Shiraz, Iran

³ CEO, Nilofar Medical Equipment Trading Company, Shiraz, Iran

⁴ Colorectal Research Center, Shiraz University of Medical Sciences, Shiraz, Iran

⁵ Central Research Laboratory, Shiraz University of Medical Sciences, Shiraz, Iran

⁶ Department of Biomedical Science, Isfahan University, Isfahan, Iran

⁷ Department of Medical Nanotechnology, School of Advanced Medical Sciences and Technologies, Shiraz University of Medical Sciences, Shiraz, Iran

⁸ Department of Mechanical Engineering, Shiraz University of Technology, Shiraz, Iran

10.31661/jbpe.v0i0.2508-1976

Abstract

Background: Conventional Sacral Nerve Stimulation (SNS) devices are widely used to treat constipation but are often limited by their lack of mechanical flexibility, which can reduce long-term therapeutic efficacy. Developing advanced electrode materials may improve stimulation performance and patient outcomes.
Objective: This experimental study aimed to introduce a proof-of-concept flexible cuff electrode composed of a graphene–polyacrylonitrile (PAN) composite and evaluate its electrochemical properties, their mechanical characteristics, and short-term functional performance in a rabbit SNS model.
Material and Methods: In this experimental study, graphene–PAN composite electrodes were fabricated and characterized for electrochemical properties, including charge injection capacity and impedance, as well as mechanical properties, such as flexibility and tensile strength. In vivo testing was conducted on rabbits to evaluate their performance in SNS therapy and their effectiveness in relieving constipation.
Results: The graphene–PAN composite electrodes demonstrated a high charge injection capacity (1062.58±73.36 µC/cm²), low impedance (31.27±2.76 Ω), and favorable mechanical flexibility (modulus: 1.31±0.45 MPa; strain at break: 27±2%). In vivo stimulation progressively improved fecal output over four days, approaching pre-injury levels.
Conclusion: Graphene-based electrodes exhibited suitable electrochemical and mechanical performance, enabling effective neural stimulation and enhanced therapeutic outcomes in constipation management. As an initial proof-of-concept, these flexible graphene-based materials represent promising candidates for future neural stimulation devices.

Highlights

Maryam Alsadat Hejazi (Google Scholar)

Alireza Mehdizadeh (Google Scholar)

Keywords

Electrodes

Electric Stimulation Therapy

Constipation

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