Funcionalização do hidroxipropilmetilcelulose (HPMC) para potencial espessante antiviral

Abstract

Recently, the world has gone through an unprecedented pandemic, which caused impacts not only on health but also in various sectors of society, such as the economy, politics, and culture. One reason SARS-CoV-2 spread só rapidly worldwide was its ability to survive for up to 72 hours on some types of surfaces, such as metal and plastic. Therefore, one of the most important measures taken to combat this virus was sanitizers. Like masks, they were fundamental in reducing transmission. Hand hygiene with alcohol-based hand sanitizers to eliminate microorganisms such as bacteria, fungi, and viruses is valid and effective in many cases. The predominant mode of action of alcohols arises from the denaturation and coagulation of proteins. The solution can be produced with ethanol, isopropanol, or n-propanol, but because they are highly volatile, they do not have significant residual activity. Therefore, this work aimed to synthesize and characterize a compound derived from the thickener, hydroxypropyl methylcellulose (HPMC), functionalized with the surfactant, sodium octane sulfonate, with potential antiviral properties and longer duration than alcohol. HPMC is a hydrophilic, biodegradable compound soluble in polar organic solvents. Sodium octane sulfonate is an anionic surfactant and, like alcohol, has the property of denaturing proteins. Being amphiphilic, having a hydrophilic and a hydrophobic part in its structure, it is capable of forming micelles and dissociating the viral envelope and capsid proteins. The procedure began with 1,8-dibromooctane, where one of the bromines (Br) was substituted by the sulfite group (SO3-) through an SN2 reaction, forming an alkyl halide. Next, the reaction of the halide with the hydroxyl group of HPMC was carried out through the Williamson ether synthesis, forming a covalent bond between the surfactant and the thickener. Comparison between the 1H NMR spectra of the products from the two steps and pure HPMC showed strong indications that the synthesis was successful. In the spectrum of the functionalized product (HPMC.C8SO3Na), the chemical shift peaks at 1.34 ppm, 1.43 ppm, 1.70 – 1.78 ppm, 1.83 – 1.90 ppm, 2.89 – 2.93 ppm, and 3.50 – 3.54 ppm were similar to those found in the spectrum of 8-bromooctane-1-sodium sulfonate. Meanwhile, the peaks at 3.43 ppm and 3.61 ppm were similar to those of the HPMC spectrum. Thickening properties were demonstrated by the product in dilution in water, as well as indications of the surfactant due to its greater solubility than the pure compound. The yield of the surfactant obtaining reaction was 76.77%, while that of HPMC.C8SO3Na was 0.69%. The results obtained indicated the need for further analysis to confirm the antiviral property, the binding between the thickener and the surfactant, and to improve the reaction yield.