Starch-based films as substrates for metal coordination: development of smart biodegradable materials

• Grant number: 25/21280-9
• Support Opportunities: Scholarships in Brazil - Scientific Initiation
• Start date: February 01, 2026
• End date: December 31, 2026
• Field of knowledge: Physical Sciences and Mathematics - Chemistry - Inorganic Chemistry
• Principal Investigator: Antonio Carlos Roveda Júnior
• Grantee: João Lucas Moraes Mello
• Host Institution: Instituto de Química de São Carlos (IQSC). Universidade de São Paulo (USP). São Carlos , SP, Brazil

Abstract

Plastic pollution is considered by the UN to be the second greatest global environmental threat, which reinforces the need for sustainable alternatives to petroleum-derived polymers. In this context, starch stands out as an abundant, renewable, biodegradable, and low-cost biopolymer that enables the production of materials capable of replacing petroleum-based polymers. Nevertheless, starch-based materials such as starch films suffer from mechanical fragility, water solubility, and low thermal stability, which limit their use in certain applications. Therefore, the search for strategies to overcome these drawbacks is an important research topic in the field of starch-based materials, aiming at the substitution of petroleum derivatives. One of the strategies employed in polysaccharides such as alginate, pectin, and chitosan is the incorporation of metal ions, such as iron and vanadium, to overcome these limitations. The incorporation of these ions promotes coordination between the polymeric matrix groups and the metal, resulting in improvements in the structural, mechanical, and barrier properties of the materials. Thus, this project aims to evaluate the incorporation of iron and vanadium ions into starch films and their effects on the structural, thermal stability, solubility, and mechanical performance of the films. In addition, the photoreactivity of iron and vanadium ions in the films will be explored, correlating changes in the Fe(III)/Fe(II) and V(V)/V(IV) oxidation states with modifications in the material properties. Furthermore, the study will investigate photochromism and photopatterning (the creation of an image by light exposure) in these materials. Therefore, this study will provide insights into the mechanisms of metal-polysaccharide interactions, aiming to develop starch-based films that are more biodegradable, resistant, stable, and functional, with potential applications in sustainable packaging, photochromism, and photopatterning. (AU)