Anticoagulant activity of cellulose nanocrystals from isora plant fibers assembled on cellulose and sio2 substrates via a layer-by-layer approach

In this study, we report the isolation of cellulose nanocrystals (CNCs) from Isora plant fibers by sulfuric acid hydrolysis and their assembly on hydrophilic cellulose and silicon-di-oxide (SiO2) surfaces via a layer-by-layer (LBL) deposition method. The isolated CNCs were monodis-persed and exhibited a length of 200-300 nm and a diameter of 10-20 nm, a negative zetapotential (34-39 mV) over a wide pH range, and high stability in water at various concentrations. The multi-layered structure, adsorbed mass, conformational changes, and anticoagulant activity of sequen-tially deposited anionic (sulfated) CNCs and cationic polyethyleneimine (PEI) on the surfaces of cellulose and SiO2 by LBL deposition were investigated using a quartz crystal microbalance tech-nique. The organization and surface features (i.e., morphology, thickness, wettability) of CNCs ad-sorbed on the surfaces of PEI deposited at different ionic strengths (50-300 mM) of sodium chloride were analysed in detail by profilometry layer-thickness, atomic force microscopy and contact angle measurements. Compared to cellulose (control sample), the total coagulation time and plasma deposition were increased and decreased, respectively, for multilayers of PEI/CNCs. This study should provide new possibilities to fabricate and tailor the physicochemical properties of multilayer films from polysaccharide-based nanocrystals for various biomedical applications.Acknowledgments: The authors acknowledge Volker Ribitsch (retired) from the University of Graz/Austria for his support and valuable discussion for this manuscript. The authors also acknowledge the financial support from the Slovenian National Research Agency ARRS (Grant No. J4-1764).Scopu