Printed Silk Microelectrode Arrays for Electrophysiological Recording and Controlled Drug Delivery

Area of Science:

• Bioelectronic Interfaces
• Biomaterials Science
• Cellular Electrophysiology

Background:

• Soft and flexible bioelectronic interfaces are crucial for high-quality recording of cellular electrical activity due to their ability to maintain intimate contact with physiological surfaces.
• Existing interfaces often struggle with the dynamic and curved nature of biological environments, limiting their effectiveness.

Purpose of the Study:

• To develop novel soft microelectrode arrays (MEAs) using silk fibroin (SF) films that serve as both recording interfaces and drug delivery systems.
• To demonstrate the fabrication versatility and functionality of these MEAs for in vitro applications.

Main Methods:

• Utilized inkjet printing to deposit substrate, conductive electrodes, insulator, and a drug-delivery nanocomposite film onto SF films.
• Fabricated carbon microelectrodes integrated within a silk substrate and insulator structure.
• Demonstrated the tuning of SF by electrical stimulation to create a permeable layer for drug delivery.

Main Results:

• Successfully fabricated thin-film devices capable of in vitro extracellular recordings of HL-1 cell action potentials.
• Showcased the development of a silk-based, multifunctional microelectrode array (MEA).
• Validated the on-demand drug delivery capability through electrically stimulated SF permeability.

Conclusions:

• The developed silk fibroin-based MEAs offer a versatile platform for simultaneous cell recording and targeted drug delivery.
• This technology facilitates in vitro drug screening through time-resolved and localized chemical stimulation.
• The soft and flexible nature of the SF interfaces ensures robust performance in physiological environments.