Conventional, Green, and Advanced Modification Techniques for Sodium Alginate Derived From Brown Seaweed

Abstract

The environment is in danger due to the increasing use of non‐biodegradable materials and plastics, and to prevent the climate crisis it causes, biopolymers are an attractive alternative to petroleum‐based products. Alginic acid or alginate has unique structural, physicochemical, and mechanical properties, including chemical composition, block structure, and molecular weight. These properties vary with the source, extraction technique, and functionalization/modification methods used to improve the alginate for commercial applications. The source of alginate is seaweed, which is abundant in marine biomass, and it has emerged as a versatile biopolymer across biomedical, pharmaceutical, food, and environmental applications due to its biodegradability and biocompatibility. It exhibits limitations in thermal stability, controlled crosslinking density, toughness, and mechanical tunability, despite its excellent properties. This study highlights methods for enhancing the properties of the alginate chain through chemical, enzymatic, and physical approaches. Furthermore, it enlightens the green approach to modifying the biopolymer. The review concludes with an overview of conventional and advanced methods for enhancing alginate and the commercial application of this functionalized biodegradable product and a critical evaluation of limitations, including future perspectives for alginate‐based materials.