Biocompatibility of electroactive polymers in tissues

TLDR

The study implanted EVAc, PE, and PANi films of various oxidation states subcutaneously in rats for 19–90 weeks and evaluated biocompatibility using histology, interstitial pressure measurements, and X‑ray photoelectron spectroscopy. All polymers showed no inflammatory response or tissue incompatibility, and low interstitial pressure confirmed their biocompatibility over the full implantation period.

Abstract

The biocompatibility of ethylene-vinyl acetate copolymer (EVAc), polyethylene (PE), and polyaniline (PANi) films in the emeraldine (EM), nigraniline (NA) and leucoemeraldine (LM) intrinsic oxidation states were assessed through subcutaneous implantation into male Sprague-Dawley rats beneath the dorsal skin, for a period ranging from 19 to 90 weeks. Histological examination, interstitial pressure measurement, and X-ray photoelectron spectroscopy (XPS) were employed to determine the biocompatibility of the polymers. The polymers did not provoke inflammatory responses in the subcutaneous tissues over the entire implantation period. Characteristics features associated with tissue-implant incompatibility were not evident near the implantation. Interstitial pressure was measured to evaluate the development of tissue. Low interstitial pressure readings on the region of implantation confirmed the biocompatibility of these polymer types. The surface composition of the electroactive aniline polymers before and after the implantation was characterized by XPS.