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Abstract Silicone is utilized widely in medical devices for its compatibility with tissues and bodily fluids, making it a versatile material for implants and wearables. To effectively bond silicone devices to biological tissues, a reliable adhesive is required to create a long‐lasting interface. BioAdheSil, a silicone‐based bioadhesive designed to provide robust adhesion on both sides of the interface is introduced here, facilitating bonding between dissimilar substrates, namely silicone devices and tissues. The adhesive's design focuses on two key aspects: wet tissue adhesion capability and tissue‐infiltration‐based long‐term integration. BioAdheSil is formulated by mixing soft silicone oligomers with siloxane coupling agents and absorbents for bonding the hydrophobic silicone device to hydrophilic tissues. Incorporation of biodegradable absorbents eliminates surface water and controls porosity, while silane crosslinkers provide interfacial strength. Over time, BioAdheSil transitions from nonpermeable to permeable through enzyme degradation, creating a porous structure that facilitates cell migration and tissue integration, potentially enabling long‐lasting adhesion. Experimental results demonstrate that BioAdheSil outperforms commercial adhesives and elicits no adverse response in rats. BioAdheSil offers practical utility for adhering silicone devices to wet tissues, including long‐term implants and transcutaneous devices. Here, its functionality is demonstrated through applications such as tracheal stents and left ventricular assist device lines.
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Multifunctional Nanomesh Enables Cellular‐Resolution, Elastic Neuroelectronics
Abstract Silicone‐based devices have the potential to achieve an ideal interface with nervous tissue but suffer from scalability, primarily due to the mechanical mismatch between established electronic materials and soft elastomer substrates. This study presents a novel approach using conventional electrode materials through multifunctional nanomesh to achieve reliable elastic microelectrodes directly on polydimethylsiloxane (PDMS) silicone with an unprecedented cellular resolution. This engineered nanomesh features an in‐plane nanoscale mesh pattern, physically embodied by a stack of three thin‐film materials by design, namely Parylene‐C for mechanical buffering, gold (Au) for electrical conduction, and Poly(3,4‐ethylenedioxythiophene)‐poly(styrenesulfonate) (PEDOT:PSS) for improved electrochemical interfacing. Nanomesh elastic neuroelectronics are validated using single‐unit recording from the small and curvilinear epidural surface of mouse dorsal root ganglia (DRG) with device self‐conformed and superior recording quality compared to plastic control devices requiring manual pressing is demonstrated. Electrode scaling studies from in vivo epidural recording further revealed the need for cellular resolution for high‐fidelity recording of single‐unit activities and compound action potentials. In addition to creating a minimally invasive device to effectively interface with DRG sensory afferents at a single‐cell resolution, this study establishes nanomeshing as a practical pathway to leverage traditional electrode materials for a new class of elastic neuroelectronics.
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- PAR ID:
- 10639550
- Publisher / Repository:
- Wiley Blackwell (John Wiley & Sons)
- Date Published:
- Journal Name:
- Advanced Materials
- Volume:
- 36
- Issue:
- 36
- ISSN:
- 0935-9648
- Format(s):
- Medium: X
- Sponsoring Org:
- National Science Foundation
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