Surface modification of polyethylenterephthalate film with primary amines using gamma radiation and aminolysis reaction for cell adhesion studies

Abstract

The success of biomaterials depends on several factors that determine their proper interaction with the biological environment. Their physical and chemical properties, such as the rigidity of the substrate and the topography and chemistry of the surface, have an important influence on cellular behavior. This work describes the modification of the surface of polyethylenterephthalate (PET) films with primary amino groups, as well as cell adhesion tests on these surfaces. Herein, gamma radiation was used to graft acryloyl chloride (AC) by an oxidative preirradiation method to obtain PET-g-AC with a grafting percent of 4.8 ± 0.07%. After grafting ethylenediamine (ED) was reacted with PET-g-AC via an aminolysis reaction to generate PET-g-EAAm where NH2 terminal groups are present on the polymer surface. The films were characterized by contact angle, FT-IR, TGA, SEM and AFM. The presence of NH2 groups on modified PET films’ surfaces was confirmed by XPS, and the amount (20.3 + 0.7 pmol mm-2) was calculated using a colorimetric method; this quantity was determined to be sufficient to carry out cell culture assays, demonstrating that PET-g-EAAm films with primary amines are biocompatible with epithelial and mesenchymal cells lines, which play a very important role in the development and design of new materials for biomedical applications.