Tailored chitosan/hyaluronan coatings for tumor cell adhesion: Effects of topography, charge density and surface composition

摘要

Immobilization of cells on surfaces can be strongly affected by several properties of a substrate, including surface properties, topography and charge density. Controlling the cell adhesion mechanism is a real challenge in biotechnological processes. Here, we assessed the influence of the average degree of deacetylation of chitosan (DD) and the polyelectrolyte solution pH on the physicochemical properties of multilayered hyaluronan/chitosan films and their ability to bind tumor cells. These functional coatings explore CD44-hyaluronate interactions to improve the capture of tumor cells (PC3 line). Film characterization was carried out using XPS, UV-Vis and scanning probe techniques such as Capacitance, KPFM and AFM-IR measurements. The increase in the solution pH from 3.0 to 5.0 was the major factor to control both the film structure and the cell capture, enhancing the number of cells adhered in a range of 1.5 to 3.5-fold. These results also suggest that limited HA availability induces cell-film adhesion, whereas more irregular and rougher surfaces inhibit this process. These findings indicate that surface chemistry and morphology are critical factors for the development of new biomaterials designed to capture cells selectively.