Fractal analysis of the formation process and morphologies of hyaluronan/chitosan nanofilms in layer-by-layer assembly

Author(s)

Hernandez-Montelongo, J. ^{[1, 2]} ; Nascimento, V. F. ^[3] ; Hernandez-Montelongo, R. ^[4] ; Beppu, M. M. ^[3] ; Cotta, M. A. ^[1]

Affiliation

^[1] Univ Estadual Campinas, Inst Fis Gleb Wataghin, Dept Fis Aplicada, BR-13083859 Campinas, SP - Brazil

^[2] Univ Catolica Temuco, Fac Ingn, Nucleo Invest Bioprod & Mat Avanzados, Temuco 4813302, La Araucania - Chile

^[3] Univ Estadual Campinas, Fac Engn Quim, BR-13083852 Campinas, SP - Brazil

^[4] Univ Guadalajara, Ctr Univ Ciencias Exactas & Ingn, Dept Elect, Guadalajara 44430, Jalisco - Mexico

• Document type: Journal article
• Source: Polymer; v. 191, MAR 16 2020.
• Web of Science Citations: 0

Abstract

In the last decade, hyaluronan (HA, polyanion) and chitosan (CHI, polycation) biopolymers have been assembled by layer-by-layer (LbL) for the synthesis of antibacterial coatings. As electrostatic interactions are the main driving force for the formation of LbL films, pH and ionic strength (IS) are important critical variables of synthesis. In this context, we used surface fractal analysis of HA/CHI films to characterize the growth process for different bilayers obtained with two pH (5 and 3) and IS values (0 and 0.1 M NaCl). Our results showed that the HA/CHI assembling is mainly affected by changes in the pH than IS. Fractal dimension (D-f) of pH 5 series presented values similar to 2.2, indicating that irregularities from the initial random adsorption process are minimized. However, when pH decreased to 3, D-f increases up to similar to 2.5, suggesting a transition to diffusion-limited aggregation. (AU)

• FAPESP's process: 13/14888-3 - Adhesion behavior of Pseudomonas aeruginosa and Staphylococcus aureus bacteria on nanostructured films based on chitosan: studies at the micro and nanoscales.
• Grantee: Jesús Jacobo Hernández Montelongo
• Support Opportunities: Scholarships in Brazil - Post-Doctoral