journal article·2026-03Open access

Nonmulberry Silk Fibroin Doping Boosts Charge Transfer and Charge Injection in Aligned Polypyrrole‐Silk Scaffolds for Low‐Voltage Neurostimulation

Rajiv Borah, Joseph Christakiran Moses, Jnanendra Upadhyay, Jitu Mani Das, Michael G. Monaghan, Biman B. Mandal

Advanced Materials Interfaces· Volume 13· Issue 6

Abstract

ABSTRACT Electroconductive biomaterials (ECBs) recreate the bioelectrical microenvironment of nerve tissue, facilitating action potential propagation and enhancing regeneration via electrical stimulation (ES). We report a pseudocapacitive ECB with high conductivity, charge density, and low impedance, combining mixed electronic‐ionic transport with reversible redox activity to deliver stable ES without electrode degradation. The scaffold comprises aligned microfibrous polypyrrole (PPy) and Bombyx mori silk fibroin (BmSF), functionalized with Antheraea assamensis silk fibroin (AaSF) rich in RGD motifs. Anionic AaSF acts as a secondary dopant for PPy, improving electrical conductivity (∼9.18 mS cm − 1 ) and charge‐transfer efficiency (∼24 Ω), while increasing charge injection at low potentials (∼0.5 µC cm −2 at 50 mV) beyond conventional bioelectrodes. Under pulsed ES at 50 mV cm − 1 , primary dorsal root ganglion neurons extended neurites up to 830 µm in 7 days. Excessive current or voltage reduced outgrowth, underscoring the importance of ES optimization. Biocompatibility tests showed AaSF functionalization enhanced cell adhesion, reduced pro‐inflammatory responses, and promoted neuronal and glial differentiation of primary adipose‐derived mesenchymal stem cells via improved intercellular communication. This work links scaffold electrochemical properties to neuronal outcomes, providing a framework for selecting ES parameters in excitable tissues. The developed biohybrid scaffold offers a promising platform for next‐generation nerve guidance conduits in regenerative therapies.
Source: crossref · Quality: baseline

Research context

OpenAlex topics: Silk-based biomaterials and applications · Planarian Biology and Electrostimulation · Advanced Sensor and Energy Harvesting Materials

SciVX discovery tags are terminology-based. OpenAlex topics are source-provided classifications.

Affiliations

Discipline of Mechanical, Manufacturing and Biomedical Engineering Trinity College Dublin Dublin Ireland

Life Sciences Division Institute of Advanced Study in Science & Technology Guwahati India

Biomaterials and Tissue Engineering Laboratory Department of Biosciences & Bioengineering Indian Institute of Technology Guwahati Guwahati Assam India

Department of Physics Dibrugarh University Dibrugarh Assam India

Department of Physics Dakshin Kamrup College, Mirza Kamrup Assam India

Advanced Materials and Bio‐Engineering Research (AMBER) Centre At Trinity College Dublin and the Royal College of Surgeons in Ireland Dublin Ireland

CÚRAM, Centre For Research in Medical Devices National University of Ireland Galway Ireland

Centre For Nanotechnology Indian Institute of Technology Guwahati Guwahati Assam India

Jyoti and Bhupat Mehta School of Health Sciences and Technology Indian Institute of Technology Guwahati Guwahati Assam India

Funding

H2020 European Research Council · Indian Institute of Technology Guwahati · Indian Council of Medical Research · Science and Engineering Research Board

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