Obtención de quitosano a partir de la desacetilación de quitina comercial, usando tratamientos alcalinos y oxidativos

Abstract

Chitin is the most abundant biopolymer on Earth after cellulose. It is found in certain living organisms, such as the exoskeletons of crustaceans, as well as in various mushrooms and filamentous fungi. The interest in this molecule lies in its great versatility and transformation potential, related to its biodegradability, biocompatibility, non-toxicity, and ability to form resistant structures. Through the process of deacetylation, chitin can be converted into chitosan, a polymer of great interest in biotechnology due to its unique properties: the ability to immobilize enzymes and cells, the formation of chelates with metal ions, biodegradability, and potential applications such as biodegradable films and coatings for pharmaceuticals and food pills. This project examines different treatments in the transformation process of chitin into chitosan to determine the most efficient method. For this purpose, chitin was biotransformed using potassium hydroxide (KOH), which acts as a strong base, breaking amide bonds and promoting the removal of acetyl groups, thereby converting them into amine groups. Additionally, sodium percarbonate (Na₂H₃C₂O₆) was used; although it is not a deacetylating agent, it can help break down complex structures, improving reaction efficiency. A total of 19 treatments were carried out in this study, varying concentrations and reaction times. The treatments were analyzed using FTIR (Fourier Transform Infrared Spectroscopy). A multivariate central analysis demonstrated that treatment B4, 1 g commercial chitin with 5 g of KOH, 6 g of Na₂H₃C₂O₆, and 30 minutes of exposure, and treatment C4, 1 g commercial chitin with 7.5 g of KOH, 3 g of Na₂H₃C₂O₆, and 30 minutes of exposure, resulted in deacetylation percentages of 16% and 15.2%, respectively.