title: Modulating Biopolymer Electrical Charge to Optimize the Assembly of Edible Multilayer Nanofilms by the Layer-by-Layer Technique.
abstract: The aim of this work was to study the influence of biopolymer (alginate, ALG; chitosan, CHI) charge on the formation of multilayer nanofilms by the layer-by-layer (LbL) technique. The electrical charge of ALG and CHI (high, medium, or low) was modulated by adjusting the pH of biopolymer solutions. The amount of biopolymer deposited in multilayers depended on the charge of ALG and CHI solutions. The lower the charge the higher the deposition rate due to the higher number of biopolymer molecules needed to neutralize the previous layer. Medium and low charge biopolymers led to a drastic change in the wettability of multilayers, with ALG layers being strongly hydrophilic and CHI layers strongly hydrophobic. The surface ζ-potential alternatively changed from negative to positive using ALG or CHI. This effect was more pronounced using highly charged biopolymers. Results obtained in this study evidenced that the multilayers properties can be tuned by controlling the biopolymer electrical charge.
authors: Department of Food Technology, Agrotecnio Center, University of Lleida , Av. Alcalde Rovira Roure 191, 25198 Lleida, Spain.
authors: Alejandra
authors: A
authors: Acevedo-Fani
authors: Department of Food Technology, Agrotecnio Center, University of Lleida , Av. Alcalde Rovira Roure 191, 25198 Lleida, Spain.
authors: Laura
authors: L
authors: Salvia-Trujillo
authors: Department of Food Technology, Agrotecnio Center, University of Lleida , Av. Alcalde Rovira Roure 191, 25198 Lleida, Spain.
authors: Robert
authors: R
authors: Soliva-Fortuny
authors: Department of Food Technology, Agrotecnio Center, University of Lleida , Av. Alcalde Rovira Roure 191, 25198 Lleida, Spain.
authors: Olga
authors: O
authors: Martín-Belloso
mesh_terms: D000464:Alginates / Q000737:chemistry*; D048271:Chitosan / Q000737:chemistry*; D020723:Glucuronic Acid / Q000737:chemistry; D006603:Hexuronic Acids / Q000737:chemistry; D006863:Hydrogen-Ion Concentration; D057927:Hydrophobic and Hydrophilic Interactions; D008567:Membranes, Artificial; D053758:Nanoparticles / Q000737:chemistry*
chemical_list: D000464:Alginates; D006603:Hexuronic Acids; D008567:Membranes, Artificial; D020723:Glucuronic Acid; D048271:Chitosan