Biomimetic polypyrrole/hyaluronic acid electrodes integrated with hyaluronidase inhibitors offer persistent electroactivity and resistance to cell binding

J Mater Chem B. 2022 Mar 9;10(10):1591-1600. doi: 10.1039/d1tb02849a.

Abstract

Conductive polymers, including polypyrrole (PPy), have garnered much attention as bioelectrodes because of their high conductivity, low interfacial resistance, environmental stability, and biocompatibility. In particular, the introduction of high-molecular weight hyaluronic acid (HA) into PPy enables the fabrication of biomimetic and biocompatible electrodes (i.e., PPy/HA) characterized by low biofouling. However, as HA is readily degraded by enzymes (i.e., hyaluronidase (HAase)) in a biological milieu, PPy/HA substantially loses its original properties, including resistance to cell adhesion and electrical activity. We found that HAase treatment of PPy/HA substantially degraded the HA moieties in PPy/HA, resulting in increased water contact angles, increased impedance, and conversion of non-cell adhesive to cell adhesive surfaces. Hence, it is desirable to mitigate HA degradation to achieve persistent performance of PPy/HA electrodes. Accordingly, we incorporated glycyrrhizin as an HAase inhibitor (HI) into PPy/HA electrodes. HI-incorporated PPy/HA (PPy/HA/HI) successfully prevented the degradation of the HA moiety and non-specific cell adhesion on the electrodes, in the presence of HAase (2.5 U mL-1), without cytotoxicity. These excellent properties allowed for maintenance of the electrical sensitivity of PPy/HA during cell culture with HAase. Altogether, biomimetic PPy/HA, which is resistant to degradation by HAase, may serve as an effective platform for the development of reliable and biocompatible bioelectrodes.

Publication types

  • Research Support, Non-U.S. Gov't

MeSH terms

  • Biomimetics
  • Electrodes
  • Hyaluronic Acid / chemistry
  • Hyaluronic Acid / pharmacology
  • Hyaluronoglucosaminidase
  • Polymers* / chemistry
  • Polymers* / pharmacology
  • Pyrroles* / chemistry
  • Pyrroles* / pharmacology

Substances

  • Polymers
  • Pyrroles
  • polypyrrole
  • Hyaluronic Acid
  • Hyaluronoglucosaminidase