Thick‐Film Carbon Electrode Deposited onto a Biodegradable Fibroin Substrate for Biosensing Applications

Abstract

This study addresses a proof‐of‐concept experiment with a biocompatible screen‐printed carbon electrode deposited onto a biocompatible and biodegradable substrate, which is made of fibroin, a protein derived from silk of the Bombyx mori silkworm. To demonstrate the sensor performance, the carbon electrode is functionalized as a glucose biosensor with the enzyme glucose oxidase and encapsulated with a silicone rubber to ensure biocompatibility of the contact wires. The carbon electrode is fabricated by means of thick‐film technology including a curing step to solidify the carbon paste. The influence of the curing temperature and curing time on the electrode morphology is analyzed via scanning electron microscopy. The electrochemical characterization of the glucose biosensor is performed by amperometric/voltammetric measurements of different glucose concentrations in phosphate buffer. Herein, systematic studies at applied potentials from 500 to 1200 mV to the carbon working electrode (vs the Ag/AgCl reference electrode) allow to determine the optimal working potential. Additionally, the influence of the curing parameters on the glucose sensitivity is examined over a time period of up to 361 days. The sensor shows a negligible cross‐sensitivity toward ascorbic acid, noradrenaline, and adrenaline. The developed biocompatible biosensor is highly promising for future in vivo and epidermal applications.

Influence of Fibroin Membrane Composition and Curing Parameters on the Performance of a Biodegradable Enzymatic Biosensor Manufactured from Silicon‐Free Carbon

“…[43,44] In this way, fibroin can be used as a mechanically resistant substrate for screen-printed carbon electrodes or as a swellable membrane for exemplary drug-delivery devices. [37,45,46] Fibroin can adopt a variety of morphologies such as sponges, fibers, or gels. [47][48][49] Thus, fibroin could even be tried as an alternative to the biomedical wound adhesive.…”

“…Further details on the preparation of fibroin membranes can be found elsewhere. [9,37] The samples for the swelling tests were prepared using the same procedure (with the formulation adjusted accordingly), as described in Section 2.6.…”

“…To circumvent these drawbacks, thick‐film technology for electrode deposition, particularly screen‐printing, enables the fabrication of a screen‐printed biosensor based on carbon electrodes on a biodegradable fibroin substrate. [ 37 ] The biosensor performance was studied regarding curing parameters, applied working electrode potential, and shelf life. The sensors demonstrated that thick‐film technology represents a promising strategy for fabricating flexible and biocompatible biosensors.…”

Transient magnesium‐based thin‐film temperature sensor on a flexible, bioabsorbable substrate for future medical applications

“…Further details of membrane preparation can be found elsewhere. [5,23,24] Fabrication of the magnesium-based resistive temperature sensor on bioabsorbable substrate…”

Biodegradable Temperature Sensor enabled using Printed Electronics

“…They function similarly to the traditional temperature sensors, detecting changes in temperature and providing valuable data for various applications including environmental monitoring, food safety, and healthcare. [4] Additionally, in fields like healthcare, biodegradable temperature sensors offer a safe and environmentally friendly option for monitoring patient vitals without the need for invasive procedures or subsequent waste management. These sensors are being utilized for realtime temperature monitoring in wound healing, drug delivery systems, agricultural monitoring, and environmental sensing.…”