Effect of polycations on stability and bioactivity of polyelectrolyte multilayers with thermoresponsive cellulose sulphate

Abstract

This thesis presents novel thermoresponsive, bioactive coatings based on PNIPAm-grafted cellulose sulphate (PCS) for polyelectrolyte multilayer (PEM) assembly via the layer-by-layer technique. Two PCS variants with different sulfation levels (PCS1: DS 0.41; PCS2: DS 0.93) were synthesized and combined with various polycations (Chitosan, Quarternized Chitosan, Poly-L-lysin). PCS2 enabled greater polycation adsorption and more stable PEMs. Surface analysis and cell studies revealed that PCS2 with quaternized chitosan (QCHI) formed highly biocompatible surfaces, promoting adhesion and proliferation of 3T3, HepG2, and HaCaT cells. In contrast, samples combining lower sulfated cellulose derivatives showed higher toxicity. Immunofluorescence confirmed enhanced cytoskeletal organization on PCS2-QCHI coatings. The study demonstrates the great potential of PCS-based PEMs as bioactive substrates for cell culture and tissue engineering applications.