Electropolymerization of organoclays and usage of synthesized polymer-clay nanocomposite as a matrix for cell adhesion

Abstract

One of the prominent topics in nanobiotechnology is the development of multifunctional biocompatible materials at the nanoscale and the creation of an artificial extracellular matrix (ECM) through the proper design of these material surfaces. In this study, a polymer-clay nanocomposite was synthesized via electropolymerization method to investigate the adhesion of U87-MG glioblastoma cells. Initially, 2-(4H-dithieno [3,2-b:2′,3′-d] pyrrol-4-yl)-3-mercapto propanoic acid (DTP-SH) and 4-(4H-dithieno [3,2-b:2′,3′-d] pyrrole-4-yl) phenethyl) aniline (DTP-NH₂) monomers were synthesized and characterized. DTP-NH₂ monomer was incorporated between montmorillonite (MMT) clay layers by ion exchange reaction and characterized using Fourier Transform Infrared Spectroscopy (FTIR), scanning electron microscopy–energy-dispersive X-ray spectroscopy (SEM–EDS), and X-Ray diffraction (XRD) techniques. The obtained (DTP-NH₂)-MMT was polymerized using the cyclic voltammetry (CV) technique on screen-printed gold (Au) electrode surface to form polymer-clay nanocomposite. For the first time in literature, a conductive polymer-based polymer-clay nanocomposite was synthesized using the electrochemical polymerization as an alternative to traditional methods. After the formation of P(DTP-NH₂)-MMT on the DTP-SH-coated Au surface, the GMT8 aptamer was covalently immobilized to generate a biofunctional surface. Electrochemical characterization of the resulting surface was subsequently performed using cyclic voltammetry (CV), differential pulse voltammetry (DPV), and electrochemical impedance spectroscopy (EIS). U87-MG glioblastoma and L929 fibroblast (negative control) cell lines were incubated on the P(DTP-NH₂)-MMT/GMT8 surface. Finally, cell adhesion was examined using DPV technique and fluorescence imaging. The results demonstrated that the aptamer-functionalized P(DTP-NH₂)-MMT surface supported significantly higher adhesion of U87-MG cells compared to the control, indicating its promising potential as a cell adhesion platform.